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
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register.
36 Call `put_var_into_stack' when you learn, belatedly, that a variable
37 previously given a pseudo-register must in fact go in the stack.
38 This function changes the DECL_RTL to be a stack slot instead of a reg
39 then scans all the RTL instructions so far generated to correct them. */
51 #include "hard-reg-set.h"
52 #include "insn-config.h"
55 #include "basic-block.h"
61 #include "integrate.h"
62 #include "langhooks.h"
64 #ifndef TRAMPOLINE_ALIGNMENT
65 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
68 #ifndef LOCAL_ALIGNMENT
69 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
72 /* Some systems use __main in a way incompatible with its use in gcc, in these
73 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
74 give the same symbol without quotes for an alternative entry point. You
75 must define both, or neither. */
77 #define NAME__MAIN "__main"
78 #define SYMBOL__MAIN __main
81 /* Round a value to the lowest integer less than it that is a multiple of
82 the required alignment. Avoid using division in case the value is
83 negative. Assume the alignment is a power of two. */
84 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
86 /* Similar, but round to the next highest integer that meets the
88 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
90 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
91 during rtl generation. If they are different register numbers, this is
92 always true. It may also be true if
93 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
94 generation. See fix_lexical_addr for details. */
96 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
97 #define NEED_SEPARATE_AP
100 /* Nonzero if function being compiled doesn't contain any calls
101 (ignoring the prologue and epilogue). This is set prior to
102 local register allocation and is valid for the remaining
104 int current_function_is_leaf;
106 /* Nonzero if function being compiled doesn't contain any instructions
107 that can throw an exception. This is set prior to final. */
109 int current_function_nothrow;
111 /* Nonzero if function being compiled doesn't modify the stack pointer
112 (ignoring the prologue and epilogue). This is only valid after
113 life_analysis has run. */
114 int current_function_sp_is_unchanging;
116 /* Nonzero if the function being compiled is a leaf function which only
117 uses leaf registers. This is valid after reload (specifically after
118 sched2) and is useful only if the port defines LEAF_REGISTERS. */
119 int current_function_uses_only_leaf_regs;
121 /* Nonzero once virtual register instantiation has been done.
122 assign_stack_local uses frame_pointer_rtx when this is nonzero.
123 calls.c:emit_library_call_value_1 uses it to set up
124 post-instantiation libcalls. */
125 int virtuals_instantiated;
127 /* These variables hold pointers to functions to create and destroy
128 target specific, per-function data structures. */
129 void (*init_machine_status) PARAMS ((struct function *));
130 void (*free_machine_status) PARAMS ((struct function *));
131 /* This variable holds a pointer to a function to register any
132 data items in the target specific, per-function data structure
133 that will need garbage collection. */
134 void (*mark_machine_status) PARAMS ((struct function *));
136 /* Likewise, but for language-specific data. */
137 void (*init_lang_status) PARAMS ((struct function *));
138 void (*save_lang_status) PARAMS ((struct function *));
139 void (*restore_lang_status) PARAMS ((struct function *));
140 void (*mark_lang_status) PARAMS ((struct function *));
141 void (*free_lang_status) PARAMS ((struct function *));
143 /* The FUNCTION_DECL for an inline function currently being expanded. */
144 tree inline_function_decl;
146 /* The currently compiled function. */
147 struct function *cfun = 0;
149 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
150 static varray_type prologue;
151 static varray_type epilogue;
153 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
155 static varray_type sibcall_epilogue;
157 /* In order to evaluate some expressions, such as function calls returning
158 structures in memory, we need to temporarily allocate stack locations.
159 We record each allocated temporary in the following structure.
161 Associated with each temporary slot is a nesting level. When we pop up
162 one level, all temporaries associated with the previous level are freed.
163 Normally, all temporaries are freed after the execution of the statement
164 in which they were created. However, if we are inside a ({...}) grouping,
165 the result may be in a temporary and hence must be preserved. If the
166 result could be in a temporary, we preserve it if we can determine which
167 one it is in. If we cannot determine which temporary may contain the
168 result, all temporaries are preserved. A temporary is preserved by
169 pretending it was allocated at the previous nesting level.
171 Automatic variables are also assigned temporary slots, at the nesting
172 level where they are defined. They are marked a "kept" so that
173 free_temp_slots will not free them. */
177 /* Points to next temporary slot. */
178 struct temp_slot *next;
179 /* The rtx to used to reference the slot. */
181 /* The rtx used to represent the address if not the address of the
182 slot above. May be an EXPR_LIST if multiple addresses exist. */
184 /* The alignment (in bits) of the slot. */
186 /* The size, in units, of the slot. */
188 /* The type of the object in the slot, or zero if it doesn't correspond
189 to a type. We use this to determine whether a slot can be reused.
190 It can be reused if objects of the type of the new slot will always
191 conflict with objects of the type of the old slot. */
193 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
195 /* Non-zero if this temporary is currently in use. */
197 /* Non-zero if this temporary has its address taken. */
199 /* Nesting level at which this slot is being used. */
201 /* Non-zero if this should survive a call to free_temp_slots. */
203 /* The offset of the slot from the frame_pointer, including extra space
204 for alignment. This info is for combine_temp_slots. */
205 HOST_WIDE_INT base_offset;
206 /* The size of the slot, including extra space for alignment. This
207 info is for combine_temp_slots. */
208 HOST_WIDE_INT full_size;
211 /* This structure is used to record MEMs or pseudos used to replace VAR, any
212 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
213 maintain this list in case two operands of an insn were required to match;
214 in that case we must ensure we use the same replacement. */
216 struct fixup_replacement
220 struct fixup_replacement *next;
223 struct insns_for_mem_entry
225 /* The KEY in HE will be a MEM. */
226 struct hash_entry he;
227 /* These are the INSNS which reference the MEM. */
231 /* Forward declarations. */
233 static rtx assign_stack_local_1 PARAMS ((enum machine_mode, HOST_WIDE_INT,
234 int, struct function *));
235 static struct temp_slot *find_temp_slot_from_address PARAMS ((rtx));
236 static void put_reg_into_stack PARAMS ((struct function *, rtx, tree,
237 enum machine_mode, enum machine_mode,
238 int, unsigned int, int,
239 struct hash_table *));
240 static void schedule_fixup_var_refs PARAMS ((struct function *, rtx, tree,
242 struct hash_table *));
243 static void fixup_var_refs PARAMS ((rtx, enum machine_mode, int, rtx,
244 struct hash_table *));
245 static struct fixup_replacement
246 *find_fixup_replacement PARAMS ((struct fixup_replacement **, rtx));
247 static void fixup_var_refs_insns PARAMS ((rtx, rtx, enum machine_mode,
249 static void fixup_var_refs_insns_with_hash
250 PARAMS ((struct hash_table *, rtx,
251 enum machine_mode, int, rtx));
252 static void fixup_var_refs_insn PARAMS ((rtx, rtx, enum machine_mode,
254 static void fixup_var_refs_1 PARAMS ((rtx, enum machine_mode, rtx *, rtx,
255 struct fixup_replacement **, rtx));
256 static rtx fixup_memory_subreg PARAMS ((rtx, rtx, int));
257 static rtx walk_fixup_memory_subreg PARAMS ((rtx, rtx, int));
258 static rtx fixup_stack_1 PARAMS ((rtx, rtx));
259 static void optimize_bit_field PARAMS ((rtx, rtx, rtx *));
260 static void instantiate_decls PARAMS ((tree, int));
261 static void instantiate_decls_1 PARAMS ((tree, int));
262 static void instantiate_decl PARAMS ((rtx, HOST_WIDE_INT, int));
263 static rtx instantiate_new_reg PARAMS ((rtx, HOST_WIDE_INT *));
264 static int instantiate_virtual_regs_1 PARAMS ((rtx *, rtx, int));
265 static void delete_handlers PARAMS ((void));
266 static void pad_to_arg_alignment PARAMS ((struct args_size *, int,
267 struct args_size *));
268 #ifndef ARGS_GROW_DOWNWARD
269 static void pad_below PARAMS ((struct args_size *, enum machine_mode,
272 static rtx round_trampoline_addr PARAMS ((rtx));
273 static rtx adjust_trampoline_addr PARAMS ((rtx));
274 static tree *identify_blocks_1 PARAMS ((rtx, tree *, tree *, tree *));
275 static void reorder_blocks_0 PARAMS ((tree));
276 static void reorder_blocks_1 PARAMS ((rtx, tree, varray_type *));
277 static void reorder_fix_fragments PARAMS ((tree));
278 static tree blocks_nreverse PARAMS ((tree));
279 static int all_blocks PARAMS ((tree, tree *));
280 static tree *get_block_vector PARAMS ((tree, int *));
281 extern tree debug_find_var_in_block_tree PARAMS ((tree, tree));
282 /* We always define `record_insns' even if its not used so that we
283 can always export `prologue_epilogue_contains'. */
284 static void record_insns PARAMS ((rtx, varray_type *)) ATTRIBUTE_UNUSED;
285 static int contains PARAMS ((rtx, varray_type));
287 static void emit_return_into_block PARAMS ((basic_block, rtx));
289 static void put_addressof_into_stack PARAMS ((rtx, struct hash_table *));
290 static bool purge_addressof_1 PARAMS ((rtx *, rtx, int, int,
291 struct hash_table *));
292 static void purge_single_hard_subreg_set PARAMS ((rtx));
293 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
294 static rtx keep_stack_depressed PARAMS ((rtx));
296 static int is_addressof PARAMS ((rtx *, void *));
297 static struct hash_entry *insns_for_mem_newfunc PARAMS ((struct hash_entry *,
300 static unsigned long insns_for_mem_hash PARAMS ((hash_table_key));
301 static bool insns_for_mem_comp PARAMS ((hash_table_key, hash_table_key));
302 static int insns_for_mem_walk PARAMS ((rtx *, void *));
303 static void compute_insns_for_mem PARAMS ((rtx, rtx, struct hash_table *));
304 static void mark_function_status PARAMS ((struct function *));
305 static void maybe_mark_struct_function PARAMS ((void *));
306 static void prepare_function_start PARAMS ((void));
307 static void do_clobber_return_reg PARAMS ((rtx, void *));
308 static void do_use_return_reg PARAMS ((rtx, void *));
310 /* Pointer to chain of `struct function' for containing functions. */
311 static struct function *outer_function_chain;
313 /* Given a function decl for a containing function,
314 return the `struct function' for it. */
317 find_function_data (decl)
322 for (p = outer_function_chain; p; p = p->outer)
329 /* Save the current context for compilation of a nested function.
330 This is called from language-specific code. The caller should use
331 the save_lang_status callback to save any language-specific state,
332 since this function knows only about language-independent
336 push_function_context_to (context)
343 if (context == current_function_decl)
344 cfun->contains_functions = 1;
347 struct function *containing = find_function_data (context);
348 containing->contains_functions = 1;
353 init_dummy_function_start ();
356 p->outer = outer_function_chain;
357 outer_function_chain = p;
358 p->fixup_var_refs_queue = 0;
360 if (save_lang_status)
361 (*save_lang_status) (p);
367 push_function_context ()
369 push_function_context_to (current_function_decl);
372 /* Restore the last saved context, at the end of a nested function.
373 This function is called from language-specific code. */
376 pop_function_context_from (context)
377 tree context ATTRIBUTE_UNUSED;
379 struct function *p = outer_function_chain;
380 struct var_refs_queue *queue;
383 outer_function_chain = p->outer;
385 current_function_decl = p->decl;
388 restore_emit_status (p);
390 if (restore_lang_status)
391 (*restore_lang_status) (p);
393 /* Finish doing put_var_into_stack for any of our variables which became
394 addressable during the nested function. If only one entry has to be
395 fixed up, just do that one. Otherwise, first make a list of MEMs that
396 are not to be unshared. */
397 if (p->fixup_var_refs_queue == 0)
399 else if (p->fixup_var_refs_queue->next == 0)
400 fixup_var_refs (p->fixup_var_refs_queue->modified,
401 p->fixup_var_refs_queue->promoted_mode,
402 p->fixup_var_refs_queue->unsignedp,
403 p->fixup_var_refs_queue->modified, 0);
408 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
409 list = gen_rtx_EXPR_LIST (VOIDmode, queue->modified, list);
411 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
412 fixup_var_refs (queue->modified, queue->promoted_mode,
413 queue->unsignedp, list, 0);
417 p->fixup_var_refs_queue = 0;
419 /* Reset variables that have known state during rtx generation. */
420 rtx_equal_function_value_matters = 1;
421 virtuals_instantiated = 0;
422 generating_concat_p = 1;
426 pop_function_context ()
428 pop_function_context_from (current_function_decl);
431 /* Clear out all parts of the state in F that can safely be discarded
432 after the function has been parsed, but not compiled, to let
433 garbage collection reclaim the memory. */
436 free_after_parsing (f)
439 /* f->expr->forced_labels is used by code generation. */
440 /* f->emit->regno_reg_rtx is used by code generation. */
441 /* f->varasm is used by code generation. */
442 /* f->eh->eh_return_stub_label is used by code generation. */
444 if (free_lang_status)
445 (*free_lang_status) (f);
446 free_stmt_status (f);
449 /* Clear out all parts of the state in F that can safely be discarded
450 after the function has been compiled, to let garbage collection
451 reclaim the memory. */
454 free_after_compilation (f)
458 free_expr_status (f);
459 free_emit_status (f);
460 free_varasm_status (f);
462 if (free_machine_status)
463 (*free_machine_status) (f);
465 if (f->x_parm_reg_stack_loc)
466 free (f->x_parm_reg_stack_loc);
468 f->x_temp_slots = NULL;
469 f->arg_offset_rtx = NULL;
470 f->return_rtx = NULL;
471 f->internal_arg_pointer = NULL;
472 f->x_nonlocal_labels = NULL;
473 f->x_nonlocal_goto_handler_slots = NULL;
474 f->x_nonlocal_goto_handler_labels = NULL;
475 f->x_nonlocal_goto_stack_level = NULL;
476 f->x_cleanup_label = NULL;
477 f->x_return_label = NULL;
478 f->x_save_expr_regs = NULL;
479 f->x_stack_slot_list = NULL;
480 f->x_rtl_expr_chain = NULL;
481 f->x_tail_recursion_label = NULL;
482 f->x_tail_recursion_reentry = NULL;
483 f->x_arg_pointer_save_area = NULL;
484 f->x_clobber_return_insn = NULL;
485 f->x_context_display = NULL;
486 f->x_trampoline_list = NULL;
487 f->x_parm_birth_insn = NULL;
488 f->x_last_parm_insn = NULL;
489 f->x_parm_reg_stack_loc = NULL;
490 f->fixup_var_refs_queue = NULL;
491 f->original_arg_vector = NULL;
492 f->original_decl_initial = NULL;
493 f->inl_last_parm_insn = NULL;
494 f->epilogue_delay_list = NULL;
497 /* Allocate fixed slots in the stack frame of the current function. */
499 /* Return size needed for stack frame based on slots so far allocated in
501 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
502 the caller may have to do that. */
505 get_func_frame_size (f)
508 #ifdef FRAME_GROWS_DOWNWARD
509 return -f->x_frame_offset;
511 return f->x_frame_offset;
515 /* Return size needed for stack frame based on slots so far allocated.
516 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
517 the caller may have to do that. */
521 return get_func_frame_size (cfun);
524 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
525 with machine mode MODE.
527 ALIGN controls the amount of alignment for the address of the slot:
528 0 means according to MODE,
529 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
530 positive specifies alignment boundary in bits.
532 We do not round to stack_boundary here.
534 FUNCTION specifies the function to allocate in. */
537 assign_stack_local_1 (mode, size, align, function)
538 enum machine_mode mode;
541 struct function *function;
544 int bigend_correction = 0;
546 int frame_off, frame_alignment, frame_phase;
553 alignment = BIGGEST_ALIGNMENT;
555 alignment = GET_MODE_ALIGNMENT (mode);
557 /* Allow the target to (possibly) increase the alignment of this
559 type = type_for_mode (mode, 0);
561 alignment = LOCAL_ALIGNMENT (type, alignment);
563 alignment /= BITS_PER_UNIT;
565 else if (align == -1)
567 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
568 size = CEIL_ROUND (size, alignment);
571 alignment = align / BITS_PER_UNIT;
573 #ifdef FRAME_GROWS_DOWNWARD
574 function->x_frame_offset -= size;
577 /* Ignore alignment we can't do with expected alignment of the boundary. */
578 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
579 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
581 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
582 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
584 /* Calculate how many bytes the start of local variables is off from
586 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
587 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
588 frame_phase = frame_off ? frame_alignment - frame_off : 0;
590 /* Round frame offset to that alignment.
591 We must be careful here, since FRAME_OFFSET might be negative and
592 division with a negative dividend isn't as well defined as we might
593 like. So we instead assume that ALIGNMENT is a power of two and
594 use logical operations which are unambiguous. */
595 #ifdef FRAME_GROWS_DOWNWARD
596 function->x_frame_offset = FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment) + frame_phase;
598 function->x_frame_offset = CEIL_ROUND (function->x_frame_offset - frame_phase, alignment) + frame_phase;
601 /* On a big-endian machine, if we are allocating more space than we will use,
602 use the least significant bytes of those that are allocated. */
603 if (BYTES_BIG_ENDIAN && mode != BLKmode)
604 bigend_correction = size - GET_MODE_SIZE (mode);
606 /* If we have already instantiated virtual registers, return the actual
607 address relative to the frame pointer. */
608 if (function == cfun && virtuals_instantiated)
609 addr = plus_constant (frame_pointer_rtx,
610 (frame_offset + bigend_correction
611 + STARTING_FRAME_OFFSET));
613 addr = plus_constant (virtual_stack_vars_rtx,
614 function->x_frame_offset + bigend_correction);
616 #ifndef FRAME_GROWS_DOWNWARD
617 function->x_frame_offset += size;
620 x = gen_rtx_MEM (mode, addr);
622 function->x_stack_slot_list
623 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
628 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
632 assign_stack_local (mode, size, align)
633 enum machine_mode mode;
637 return assign_stack_local_1 (mode, size, align, cfun);
640 /* Allocate a temporary stack slot and record it for possible later
643 MODE is the machine mode to be given to the returned rtx.
645 SIZE is the size in units of the space required. We do no rounding here
646 since assign_stack_local will do any required rounding.
648 KEEP is 1 if this slot is to be retained after a call to
649 free_temp_slots. Automatic variables for a block are allocated
650 with this flag. KEEP is 2 if we allocate a longer term temporary,
651 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
652 if we are to allocate something at an inner level to be treated as
653 a variable in the block (e.g., a SAVE_EXPR).
655 TYPE is the type that will be used for the stack slot. */
658 assign_stack_temp_for_type (mode, size, keep, type)
659 enum machine_mode mode;
665 struct temp_slot *p, *best_p = 0;
667 /* If SIZE is -1 it means that somebody tried to allocate a temporary
668 of a variable size. */
673 align = BIGGEST_ALIGNMENT;
675 align = GET_MODE_ALIGNMENT (mode);
678 type = type_for_mode (mode, 0);
681 align = LOCAL_ALIGNMENT (type, align);
683 /* Try to find an available, already-allocated temporary of the proper
684 mode which meets the size and alignment requirements. Choose the
685 smallest one with the closest alignment. */
686 for (p = temp_slots; p; p = p->next)
687 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
689 && objects_must_conflict_p (p->type, type)
690 && (best_p == 0 || best_p->size > p->size
691 || (best_p->size == p->size && best_p->align > p->align)))
693 if (p->align == align && p->size == size)
701 /* Make our best, if any, the one to use. */
704 /* If there are enough aligned bytes left over, make them into a new
705 temp_slot so that the extra bytes don't get wasted. Do this only
706 for BLKmode slots, so that we can be sure of the alignment. */
707 if (GET_MODE (best_p->slot) == BLKmode)
709 int alignment = best_p->align / BITS_PER_UNIT;
710 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
712 if (best_p->size - rounded_size >= alignment)
714 p = (struct temp_slot *) ggc_alloc (sizeof (struct temp_slot));
715 p->in_use = p->addr_taken = 0;
716 p->size = best_p->size - rounded_size;
717 p->base_offset = best_p->base_offset + rounded_size;
718 p->full_size = best_p->full_size - rounded_size;
719 p->slot = gen_rtx_MEM (BLKmode,
720 plus_constant (XEXP (best_p->slot, 0),
722 p->align = best_p->align;
725 p->type = best_p->type;
726 p->next = temp_slots;
729 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
732 best_p->size = rounded_size;
733 best_p->full_size = rounded_size;
740 /* If we still didn't find one, make a new temporary. */
743 HOST_WIDE_INT frame_offset_old = frame_offset;
745 p = (struct temp_slot *) ggc_alloc (sizeof (struct temp_slot));
747 /* We are passing an explicit alignment request to assign_stack_local.
748 One side effect of that is assign_stack_local will not round SIZE
749 to ensure the frame offset remains suitably aligned.
751 So for requests which depended on the rounding of SIZE, we go ahead
752 and round it now. We also make sure ALIGNMENT is at least
753 BIGGEST_ALIGNMENT. */
754 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
756 p->slot = assign_stack_local (mode,
758 ? CEIL_ROUND (size, align / BITS_PER_UNIT)
764 /* The following slot size computation is necessary because we don't
765 know the actual size of the temporary slot until assign_stack_local
766 has performed all the frame alignment and size rounding for the
767 requested temporary. Note that extra space added for alignment
768 can be either above or below this stack slot depending on which
769 way the frame grows. We include the extra space if and only if it
770 is above this slot. */
771 #ifdef FRAME_GROWS_DOWNWARD
772 p->size = frame_offset_old - frame_offset;
777 /* Now define the fields used by combine_temp_slots. */
778 #ifdef FRAME_GROWS_DOWNWARD
779 p->base_offset = frame_offset;
780 p->full_size = frame_offset_old - frame_offset;
782 p->base_offset = frame_offset_old;
783 p->full_size = frame_offset - frame_offset_old;
786 p->next = temp_slots;
792 p->rtl_expr = seq_rtl_expr;
797 p->level = target_temp_slot_level;
802 p->level = var_temp_slot_level;
807 p->level = temp_slot_level;
811 /* We may be reusing an old slot, so clear any MEM flags that may have been
813 RTX_UNCHANGING_P (p->slot) = 0;
814 MEM_IN_STRUCT_P (p->slot) = 0;
815 MEM_SCALAR_P (p->slot) = 0;
816 MEM_VOLATILE_P (p->slot) = 0;
817 set_mem_alias_set (p->slot, 0);
819 /* If we know the alias set for the memory that will be used, use
820 it. If there's no TYPE, then we don't know anything about the
821 alias set for the memory. */
822 set_mem_alias_set (p->slot, type ? get_alias_set (type) : 0);
823 set_mem_align (p->slot, align);
825 /* If a type is specified, set the relevant flags. */
828 RTX_UNCHANGING_P (p->slot) = TYPE_READONLY (type);
829 MEM_VOLATILE_P (p->slot) = TYPE_VOLATILE (type);
830 MEM_SET_IN_STRUCT_P (p->slot, AGGREGATE_TYPE_P (type));
836 /* Allocate a temporary stack slot and record it for possible later
837 reuse. First three arguments are same as in preceding function. */
840 assign_stack_temp (mode, size, keep)
841 enum machine_mode mode;
845 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
848 /* Assign a temporary of given TYPE.
849 KEEP is as for assign_stack_temp.
850 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
851 it is 0 if a register is OK.
852 DONT_PROMOTE is 1 if we should not promote values in register
856 assign_temp (type, keep, memory_required, dont_promote)
860 int dont_promote ATTRIBUTE_UNUSED;
862 enum machine_mode mode = TYPE_MODE (type);
863 #ifndef PROMOTE_FOR_CALL_ONLY
864 int unsignedp = TREE_UNSIGNED (type);
867 if (mode == BLKmode || memory_required)
869 HOST_WIDE_INT size = int_size_in_bytes (type);
872 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
873 problems with allocating the stack space. */
877 /* Unfortunately, we don't yet know how to allocate variable-sized
878 temporaries. However, sometimes we have a fixed upper limit on
879 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
880 instead. This is the case for Chill variable-sized strings. */
881 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
882 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
883 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
884 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
886 tmp = assign_stack_temp_for_type (mode, size, keep, type);
890 #ifndef PROMOTE_FOR_CALL_ONLY
892 mode = promote_mode (type, mode, &unsignedp, 0);
895 return gen_reg_rtx (mode);
898 /* Combine temporary stack slots which are adjacent on the stack.
900 This allows for better use of already allocated stack space. This is only
901 done for BLKmode slots because we can be sure that we won't have alignment
902 problems in this case. */
905 combine_temp_slots ()
907 struct temp_slot *p, *q;
908 struct temp_slot *prev_p, *prev_q;
911 /* We can't combine slots, because the information about which slot
912 is in which alias set will be lost. */
913 if (flag_strict_aliasing)
916 /* If there are a lot of temp slots, don't do anything unless
917 high levels of optimization. */
918 if (! flag_expensive_optimizations)
919 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
920 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
923 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
927 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
928 for (q = p->next, prev_q = p; q; q = prev_q->next)
931 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
933 if (p->base_offset + p->full_size == q->base_offset)
935 /* Q comes after P; combine Q into P. */
937 p->full_size += q->full_size;
940 else if (q->base_offset + q->full_size == p->base_offset)
942 /* P comes after Q; combine P into Q. */
944 q->full_size += p->full_size;
949 /* Either delete Q or advance past it. */
951 prev_q->next = q->next;
955 /* Either delete P or advance past it. */
959 prev_p->next = p->next;
961 temp_slots = p->next;
968 /* Find the temp slot corresponding to the object at address X. */
970 static struct temp_slot *
971 find_temp_slot_from_address (x)
977 for (p = temp_slots; p; p = p->next)
982 else if (XEXP (p->slot, 0) == x
984 || (GET_CODE (x) == PLUS
985 && XEXP (x, 0) == virtual_stack_vars_rtx
986 && GET_CODE (XEXP (x, 1)) == CONST_INT
987 && INTVAL (XEXP (x, 1)) >= p->base_offset
988 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
991 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
992 for (next = p->address; next; next = XEXP (next, 1))
993 if (XEXP (next, 0) == x)
997 /* If we have a sum involving a register, see if it points to a temp
999 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
1000 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
1002 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
1003 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1009 /* Indicate that NEW is an alternate way of referring to the temp slot
1010 that previously was known by OLD. */
1013 update_temp_slot_address (old, new)
1016 struct temp_slot *p;
1018 if (rtx_equal_p (old, new))
1021 p = find_temp_slot_from_address (old);
1023 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1024 is a register, see if one operand of the PLUS is a temporary
1025 location. If so, NEW points into it. Otherwise, if both OLD and
1026 NEW are a PLUS and if there is a register in common between them.
1027 If so, try a recursive call on those values. */
1030 if (GET_CODE (old) != PLUS)
1033 if (GET_CODE (new) == REG)
1035 update_temp_slot_address (XEXP (old, 0), new);
1036 update_temp_slot_address (XEXP (old, 1), new);
1039 else if (GET_CODE (new) != PLUS)
1042 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1043 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1044 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1045 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1046 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1047 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1048 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1049 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1054 /* Otherwise add an alias for the temp's address. */
1055 else if (p->address == 0)
1059 if (GET_CODE (p->address) != EXPR_LIST)
1060 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1062 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1066 /* If X could be a reference to a temporary slot, mark the fact that its
1067 address was taken. */
1070 mark_temp_addr_taken (x)
1073 struct temp_slot *p;
1078 /* If X is not in memory or is at a constant address, it cannot be in
1079 a temporary slot. */
1080 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1083 p = find_temp_slot_from_address (XEXP (x, 0));
1088 /* If X could be a reference to a temporary slot, mark that slot as
1089 belonging to the to one level higher than the current level. If X
1090 matched one of our slots, just mark that one. Otherwise, we can't
1091 easily predict which it is, so upgrade all of them. Kept slots
1092 need not be touched.
1094 This is called when an ({...}) construct occurs and a statement
1095 returns a value in memory. */
1098 preserve_temp_slots (x)
1101 struct temp_slot *p = 0;
1103 /* If there is no result, we still might have some objects whose address
1104 were taken, so we need to make sure they stay around. */
1107 for (p = temp_slots; p; p = p->next)
1108 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1114 /* If X is a register that is being used as a pointer, see if we have
1115 a temporary slot we know it points to. To be consistent with
1116 the code below, we really should preserve all non-kept slots
1117 if we can't find a match, but that seems to be much too costly. */
1118 if (GET_CODE (x) == REG && REG_POINTER (x))
1119 p = find_temp_slot_from_address (x);
1121 /* If X is not in memory or is at a constant address, it cannot be in
1122 a temporary slot, but it can contain something whose address was
1124 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1126 for (p = temp_slots; p; p = p->next)
1127 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1133 /* First see if we can find a match. */
1135 p = find_temp_slot_from_address (XEXP (x, 0));
1139 /* Move everything at our level whose address was taken to our new
1140 level in case we used its address. */
1141 struct temp_slot *q;
1143 if (p->level == temp_slot_level)
1145 for (q = temp_slots; q; q = q->next)
1146 if (q != p && q->addr_taken && q->level == p->level)
1155 /* Otherwise, preserve all non-kept slots at this level. */
1156 for (p = temp_slots; p; p = p->next)
1157 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1161 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1162 with that RTL_EXPR, promote it into a temporary slot at the present
1163 level so it will not be freed when we free slots made in the
1167 preserve_rtl_expr_result (x)
1170 struct temp_slot *p;
1172 /* If X is not in memory or is at a constant address, it cannot be in
1173 a temporary slot. */
1174 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1177 /* If we can find a match, move it to our level unless it is already at
1179 p = find_temp_slot_from_address (XEXP (x, 0));
1182 p->level = MIN (p->level, temp_slot_level);
1189 /* Free all temporaries used so far. This is normally called at the end
1190 of generating code for a statement. Don't free any temporaries
1191 currently in use for an RTL_EXPR that hasn't yet been emitted.
1192 We could eventually do better than this since it can be reused while
1193 generating the same RTL_EXPR, but this is complex and probably not
1199 struct temp_slot *p;
1201 for (p = temp_slots; p; p = p->next)
1202 if (p->in_use && p->level == temp_slot_level && ! p->keep
1203 && p->rtl_expr == 0)
1206 combine_temp_slots ();
1209 /* Free all temporary slots used in T, an RTL_EXPR node. */
1212 free_temps_for_rtl_expr (t)
1215 struct temp_slot *p;
1217 for (p = temp_slots; p; p = p->next)
1218 if (p->rtl_expr == t)
1220 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1221 needs to be preserved. This can happen if a temporary in
1222 the RTL_EXPR was addressed; preserve_temp_slots will move
1223 the temporary into a higher level. */
1224 if (temp_slot_level <= p->level)
1227 p->rtl_expr = NULL_TREE;
1230 combine_temp_slots ();
1233 /* Mark all temporaries ever allocated in this function as not suitable
1234 for reuse until the current level is exited. */
1237 mark_all_temps_used ()
1239 struct temp_slot *p;
1241 for (p = temp_slots; p; p = p->next)
1243 p->in_use = p->keep = 1;
1244 p->level = MIN (p->level, temp_slot_level);
1248 /* Push deeper into the nesting level for stack temporaries. */
1256 /* Likewise, but save the new level as the place to allocate variables
1261 push_temp_slots_for_block ()
1265 var_temp_slot_level = temp_slot_level;
1268 /* Likewise, but save the new level as the place to allocate temporaries
1269 for TARGET_EXPRs. */
1272 push_temp_slots_for_target ()
1276 target_temp_slot_level = temp_slot_level;
1279 /* Set and get the value of target_temp_slot_level. The only
1280 permitted use of these functions is to save and restore this value. */
1283 get_target_temp_slot_level ()
1285 return target_temp_slot_level;
1289 set_target_temp_slot_level (level)
1292 target_temp_slot_level = level;
1296 /* Pop a temporary nesting level. All slots in use in the current level
1302 struct temp_slot *p;
1304 for (p = temp_slots; p; p = p->next)
1305 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1308 combine_temp_slots ();
1313 /* Initialize temporary slots. */
1318 /* We have not allocated any temporaries yet. */
1320 temp_slot_level = 0;
1321 var_temp_slot_level = 0;
1322 target_temp_slot_level = 0;
1325 /* Retroactively move an auto variable from a register to a stack slot.
1326 This is done when an address-reference to the variable is seen. */
1329 put_var_into_stack (decl)
1333 enum machine_mode promoted_mode, decl_mode;
1334 struct function *function = 0;
1336 int can_use_addressof;
1337 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1338 int usedp = (TREE_USED (decl)
1339 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1341 context = decl_function_context (decl);
1343 /* Get the current rtl used for this object and its original mode. */
1344 reg = (TREE_CODE (decl) == SAVE_EXPR
1345 ? SAVE_EXPR_RTL (decl)
1346 : DECL_RTL_IF_SET (decl));
1348 /* No need to do anything if decl has no rtx yet
1349 since in that case caller is setting TREE_ADDRESSABLE
1350 and a stack slot will be assigned when the rtl is made. */
1354 /* Get the declared mode for this object. */
1355 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1356 : DECL_MODE (decl));
1357 /* Get the mode it's actually stored in. */
1358 promoted_mode = GET_MODE (reg);
1360 /* If this variable comes from an outer function, find that
1361 function's saved context. Don't use find_function_data here,
1362 because it might not be in any active function.
1363 FIXME: Is that really supposed to happen?
1364 It does in ObjC at least. */
1365 if (context != current_function_decl && context != inline_function_decl)
1366 for (function = outer_function_chain; function; function = function->outer)
1367 if (function->decl == context)
1370 /* If this is a variable-size object with a pseudo to address it,
1371 put that pseudo into the stack, if the var is nonlocal. */
1372 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1373 && GET_CODE (reg) == MEM
1374 && GET_CODE (XEXP (reg, 0)) == REG
1375 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1377 reg = XEXP (reg, 0);
1378 decl_mode = promoted_mode = GET_MODE (reg);
1384 /* FIXME make it work for promoted modes too */
1385 && decl_mode == promoted_mode
1386 #ifdef NON_SAVING_SETJMP
1387 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1391 /* If we can't use ADDRESSOF, make sure we see through one we already
1393 if (! can_use_addressof && GET_CODE (reg) == MEM
1394 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1395 reg = XEXP (XEXP (reg, 0), 0);
1397 /* Now we should have a value that resides in one or more pseudo regs. */
1399 if (GET_CODE (reg) == REG)
1401 /* If this variable lives in the current function and we don't need
1402 to put things in the stack for the sake of setjmp, try to keep it
1403 in a register until we know we actually need the address. */
1404 if (can_use_addressof)
1405 gen_mem_addressof (reg, decl);
1407 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1408 decl_mode, volatilep, 0, usedp, 0);
1410 else if (GET_CODE (reg) == CONCAT)
1412 /* A CONCAT contains two pseudos; put them both in the stack.
1413 We do it so they end up consecutive.
1414 We fixup references to the parts only after we fixup references
1415 to the whole CONCAT, lest we do double fixups for the latter
1417 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1418 tree part_type = type_for_mode (part_mode, 0);
1419 rtx lopart = XEXP (reg, 0);
1420 rtx hipart = XEXP (reg, 1);
1421 #ifdef FRAME_GROWS_DOWNWARD
1422 /* Since part 0 should have a lower address, do it second. */
1423 put_reg_into_stack (function, hipart, part_type, part_mode,
1424 part_mode, volatilep, 0, 0, 0);
1425 put_reg_into_stack (function, lopart, part_type, part_mode,
1426 part_mode, volatilep, 0, 0, 0);
1428 put_reg_into_stack (function, lopart, part_type, part_mode,
1429 part_mode, volatilep, 0, 0, 0);
1430 put_reg_into_stack (function, hipart, part_type, part_mode,
1431 part_mode, volatilep, 0, 0, 0);
1434 /* Change the CONCAT into a combined MEM for both parts. */
1435 PUT_CODE (reg, MEM);
1436 MEM_ATTRS (reg) = 0;
1438 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1439 already computed alias sets. Here we want to re-generate. */
1441 SET_DECL_RTL (decl, NULL);
1442 set_mem_attributes (reg, decl, 1);
1444 SET_DECL_RTL (decl, reg);
1446 /* The two parts are in memory order already.
1447 Use the lower parts address as ours. */
1448 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1449 /* Prevent sharing of rtl that might lose. */
1450 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1451 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1454 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1456 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1457 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1464 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1465 into the stack frame of FUNCTION (0 means the current function).
1466 DECL_MODE is the machine mode of the user-level data type.
1467 PROMOTED_MODE is the machine mode of the register.
1468 VOLATILE_P is nonzero if this is for a "volatile" decl.
1469 USED_P is nonzero if this reg might have already been used in an insn. */
1472 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1473 original_regno, used_p, ht)
1474 struct function *function;
1477 enum machine_mode promoted_mode, decl_mode;
1479 unsigned int original_regno;
1481 struct hash_table *ht;
1483 struct function *func = function ? function : cfun;
1485 unsigned int regno = original_regno;
1488 regno = REGNO (reg);
1490 if (regno < func->x_max_parm_reg)
1491 new = func->x_parm_reg_stack_loc[regno];
1494 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1496 PUT_CODE (reg, MEM);
1497 PUT_MODE (reg, decl_mode);
1498 XEXP (reg, 0) = XEXP (new, 0);
1499 MEM_ATTRS (reg) = 0;
1500 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1501 MEM_VOLATILE_P (reg) = volatile_p;
1503 /* If this is a memory ref that contains aggregate components,
1504 mark it as such for cse and loop optimize. If we are reusing a
1505 previously generated stack slot, then we need to copy the bit in
1506 case it was set for other reasons. For instance, it is set for
1507 __builtin_va_alist. */
1510 MEM_SET_IN_STRUCT_P (reg,
1511 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1512 set_mem_alias_set (reg, get_alias_set (type));
1516 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1519 /* Make sure that all refs to the variable, previously made
1520 when it was a register, are fixed up to be valid again.
1521 See function above for meaning of arguments. */
1524 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht)
1525 struct function *function;
1528 enum machine_mode promoted_mode;
1529 struct hash_table *ht;
1531 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1535 struct var_refs_queue *temp;
1538 = (struct var_refs_queue *) ggc_alloc (sizeof (struct var_refs_queue));
1539 temp->modified = reg;
1540 temp->promoted_mode = promoted_mode;
1541 temp->unsignedp = unsigned_p;
1542 temp->next = function->fixup_var_refs_queue;
1543 function->fixup_var_refs_queue = temp;
1546 /* Variable is local; fix it up now. */
1547 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht);
1551 fixup_var_refs (var, promoted_mode, unsignedp, may_share, ht)
1553 enum machine_mode promoted_mode;
1555 struct hash_table *ht;
1559 rtx first_insn = get_insns ();
1560 struct sequence_stack *stack = seq_stack;
1561 tree rtl_exps = rtl_expr_chain;
1563 /* If there's a hash table, it must record all uses of VAR. */
1568 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp,
1573 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1574 stack == 0, may_share);
1576 /* Scan all pending sequences too. */
1577 for (; stack; stack = stack->next)
1579 push_to_full_sequence (stack->first, stack->last);
1580 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1581 stack->next != 0, may_share);
1582 /* Update remembered end of sequence
1583 in case we added an insn at the end. */
1584 stack->last = get_last_insn ();
1588 /* Scan all waiting RTL_EXPRs too. */
1589 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1591 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1592 if (seq != const0_rtx && seq != 0)
1594 push_to_sequence (seq);
1595 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1602 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1603 some part of an insn. Return a struct fixup_replacement whose OLD
1604 value is equal to X. Allocate a new structure if no such entry exists. */
1606 static struct fixup_replacement *
1607 find_fixup_replacement (replacements, x)
1608 struct fixup_replacement **replacements;
1611 struct fixup_replacement *p;
1613 /* See if we have already replaced this. */
1614 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1619 p = (struct fixup_replacement *) xmalloc (sizeof (struct fixup_replacement));
1622 p->next = *replacements;
1629 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1630 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1631 for the current function. MAY_SHARE is either a MEM that is not
1632 to be unshared or a list of them. */
1635 fixup_var_refs_insns (insn, var, promoted_mode, unsignedp, toplevel, may_share)
1638 enum machine_mode promoted_mode;
1645 /* fixup_var_refs_insn might modify insn, so save its next
1647 rtx next = NEXT_INSN (insn);
1649 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1650 the three sequences they (potentially) contain, and process
1651 them recursively. The CALL_INSN itself is not interesting. */
1653 if (GET_CODE (insn) == CALL_INSN
1654 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1658 /* Look at the Normal call, sibling call and tail recursion
1659 sequences attached to the CALL_PLACEHOLDER. */
1660 for (i = 0; i < 3; i++)
1662 rtx seq = XEXP (PATTERN (insn), i);
1665 push_to_sequence (seq);
1666 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1668 XEXP (PATTERN (insn), i) = get_insns ();
1674 else if (INSN_P (insn))
1675 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel,
1682 /* Look up the insns which reference VAR in HT and fix them up. Other
1683 arguments are the same as fixup_var_refs_insns.
1685 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1686 because the hash table will point straight to the interesting insn
1687 (inside the CALL_PLACEHOLDER). */
1690 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp, may_share)
1691 struct hash_table *ht;
1693 enum machine_mode promoted_mode;
1697 struct insns_for_mem_entry *ime
1698 = (struct insns_for_mem_entry *) hash_lookup (ht, var,
1699 /*create=*/0, /*copy=*/0);
1702 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1))
1703 if (INSN_P (XEXP (insn_list, 0)))
1704 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode,
1705 unsignedp, 1, may_share);
1709 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1710 the insn under examination, VAR is the variable to fix up
1711 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1712 TOPLEVEL is nonzero if this is the main insn chain for this
1716 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel, no_share)
1719 enum machine_mode promoted_mode;
1725 rtx set, prev, prev_set;
1728 /* Remember the notes in case we delete the insn. */
1729 note = REG_NOTES (insn);
1731 /* If this is a CLOBBER of VAR, delete it.
1733 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1734 and REG_RETVAL notes too. */
1735 if (GET_CODE (PATTERN (insn)) == CLOBBER
1736 && (XEXP (PATTERN (insn), 0) == var
1737 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1738 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1739 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1741 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1742 /* The REG_LIBCALL note will go away since we are going to
1743 turn INSN into a NOTE, so just delete the
1744 corresponding REG_RETVAL note. */
1745 remove_note (XEXP (note, 0),
1746 find_reg_note (XEXP (note, 0), REG_RETVAL,
1752 /* The insn to load VAR from a home in the arglist
1753 is now a no-op. When we see it, just delete it.
1754 Similarly if this is storing VAR from a register from which
1755 it was loaded in the previous insn. This will occur
1756 when an ADDRESSOF was made for an arglist slot. */
1758 && (set = single_set (insn)) != 0
1759 && SET_DEST (set) == var
1760 /* If this represents the result of an insn group,
1761 don't delete the insn. */
1762 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1763 && (rtx_equal_p (SET_SRC (set), var)
1764 || (GET_CODE (SET_SRC (set)) == REG
1765 && (prev = prev_nonnote_insn (insn)) != 0
1766 && (prev_set = single_set (prev)) != 0
1767 && SET_DEST (prev_set) == SET_SRC (set)
1768 && rtx_equal_p (SET_SRC (prev_set), var))))
1774 struct fixup_replacement *replacements = 0;
1775 rtx next_insn = NEXT_INSN (insn);
1777 if (SMALL_REGISTER_CLASSES)
1779 /* If the insn that copies the results of a CALL_INSN
1780 into a pseudo now references VAR, we have to use an
1781 intermediate pseudo since we want the life of the
1782 return value register to be only a single insn.
1784 If we don't use an intermediate pseudo, such things as
1785 address computations to make the address of VAR valid
1786 if it is not can be placed between the CALL_INSN and INSN.
1788 To make sure this doesn't happen, we record the destination
1789 of the CALL_INSN and see if the next insn uses both that
1792 if (call_dest != 0 && GET_CODE (insn) == INSN
1793 && reg_mentioned_p (var, PATTERN (insn))
1794 && reg_mentioned_p (call_dest, PATTERN (insn)))
1796 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1798 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1800 PATTERN (insn) = replace_rtx (PATTERN (insn),
1804 if (GET_CODE (insn) == CALL_INSN
1805 && GET_CODE (PATTERN (insn)) == SET)
1806 call_dest = SET_DEST (PATTERN (insn));
1807 else if (GET_CODE (insn) == CALL_INSN
1808 && GET_CODE (PATTERN (insn)) == PARALLEL
1809 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1810 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1815 /* See if we have to do anything to INSN now that VAR is in
1816 memory. If it needs to be loaded into a pseudo, use a single
1817 pseudo for the entire insn in case there is a MATCH_DUP
1818 between two operands. We pass a pointer to the head of
1819 a list of struct fixup_replacements. If fixup_var_refs_1
1820 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1821 it will record them in this list.
1823 If it allocated a pseudo for any replacement, we copy into
1826 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1827 &replacements, no_share);
1829 /* If this is last_parm_insn, and any instructions were output
1830 after it to fix it up, then we must set last_parm_insn to
1831 the last such instruction emitted. */
1832 if (insn == last_parm_insn)
1833 last_parm_insn = PREV_INSN (next_insn);
1835 while (replacements)
1837 struct fixup_replacement *next;
1839 if (GET_CODE (replacements->new) == REG)
1844 /* OLD might be a (subreg (mem)). */
1845 if (GET_CODE (replacements->old) == SUBREG)
1847 = fixup_memory_subreg (replacements->old, insn, 0);
1850 = fixup_stack_1 (replacements->old, insn);
1852 insert_before = insn;
1854 /* If we are changing the mode, do a conversion.
1855 This might be wasteful, but combine.c will
1856 eliminate much of the waste. */
1858 if (GET_MODE (replacements->new)
1859 != GET_MODE (replacements->old))
1862 convert_move (replacements->new,
1863 replacements->old, unsignedp);
1864 seq = gen_sequence ();
1868 seq = gen_move_insn (replacements->new,
1871 emit_insn_before (seq, insert_before);
1874 next = replacements->next;
1875 free (replacements);
1876 replacements = next;
1880 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1881 But don't touch other insns referred to by reg-notes;
1882 we will get them elsewhere. */
1885 if (GET_CODE (note) != INSN_LIST)
1887 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
1888 note = XEXP (note, 1);
1892 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1893 See if the rtx expression at *LOC in INSN needs to be changed.
1895 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1896 contain a list of original rtx's and replacements. If we find that we need
1897 to modify this insn by replacing a memory reference with a pseudo or by
1898 making a new MEM to implement a SUBREG, we consult that list to see if
1899 we have already chosen a replacement. If none has already been allocated,
1900 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1901 or the SUBREG, as appropriate, to the pseudo. */
1904 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements, no_share)
1906 enum machine_mode promoted_mode;
1909 struct fixup_replacement **replacements;
1914 RTX_CODE code = GET_CODE (x);
1917 struct fixup_replacement *replacement;
1922 if (XEXP (x, 0) == var)
1924 /* Prevent sharing of rtl that might lose. */
1925 rtx sub = copy_rtx (XEXP (var, 0));
1927 if (! validate_change (insn, loc, sub, 0))
1929 rtx y = gen_reg_rtx (GET_MODE (sub));
1932 /* We should be able to replace with a register or all is lost.
1933 Note that we can't use validate_change to verify this, since
1934 we're not caring for replacing all dups simultaneously. */
1935 if (! validate_replace_rtx (*loc, y, insn))
1938 /* Careful! First try to recognize a direct move of the
1939 value, mimicking how things are done in gen_reload wrt
1940 PLUS. Consider what happens when insn is a conditional
1941 move instruction and addsi3 clobbers flags. */
1944 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1945 seq = gen_sequence ();
1948 if (recog_memoized (new_insn) < 0)
1950 /* That failed. Fall back on force_operand and hope. */
1953 sub = force_operand (sub, y);
1955 emit_insn (gen_move_insn (y, sub));
1956 seq = gen_sequence ();
1961 /* Don't separate setter from user. */
1962 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1963 insn = PREV_INSN (insn);
1966 emit_insn_before (seq, insn);
1974 /* If we already have a replacement, use it. Otherwise,
1975 try to fix up this address in case it is invalid. */
1977 replacement = find_fixup_replacement (replacements, var);
1978 if (replacement->new)
1980 *loc = replacement->new;
1984 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1986 /* Unless we are forcing memory to register or we changed the mode,
1987 we can leave things the way they are if the insn is valid. */
1989 INSN_CODE (insn) = -1;
1990 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1991 && recog_memoized (insn) >= 0)
1994 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1998 /* If X contains VAR, we need to unshare it here so that we update
1999 each occurrence separately. But all identical MEMs in one insn
2000 must be replaced with the same rtx because of the possibility of
2003 if (reg_mentioned_p (var, x))
2005 replacement = find_fixup_replacement (replacements, x);
2006 if (replacement->new == 0)
2007 replacement->new = copy_most_rtx (x, no_share);
2009 *loc = x = replacement->new;
2010 code = GET_CODE (x);
2027 /* Note that in some cases those types of expressions are altered
2028 by optimize_bit_field, and do not survive to get here. */
2029 if (XEXP (x, 0) == var
2030 || (GET_CODE (XEXP (x, 0)) == SUBREG
2031 && SUBREG_REG (XEXP (x, 0)) == var))
2033 /* Get TEM as a valid MEM in the mode presently in the insn.
2035 We don't worry about the possibility of MATCH_DUP here; it
2036 is highly unlikely and would be tricky to handle. */
2039 if (GET_CODE (tem) == SUBREG)
2041 if (GET_MODE_BITSIZE (GET_MODE (tem))
2042 > GET_MODE_BITSIZE (GET_MODE (var)))
2044 replacement = find_fixup_replacement (replacements, var);
2045 if (replacement->new == 0)
2046 replacement->new = gen_reg_rtx (GET_MODE (var));
2047 SUBREG_REG (tem) = replacement->new;
2049 /* The following code works only if we have a MEM, so we
2050 need to handle the subreg here. We directly substitute
2051 it assuming that a subreg must be OK here. We already
2052 scheduled a replacement to copy the mem into the
2058 tem = fixup_memory_subreg (tem, insn, 0);
2061 tem = fixup_stack_1 (tem, insn);
2063 /* Unless we want to load from memory, get TEM into the proper mode
2064 for an extract from memory. This can only be done if the
2065 extract is at a constant position and length. */
2067 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2068 && GET_CODE (XEXP (x, 2)) == CONST_INT
2069 && ! mode_dependent_address_p (XEXP (tem, 0))
2070 && ! MEM_VOLATILE_P (tem))
2072 enum machine_mode wanted_mode = VOIDmode;
2073 enum machine_mode is_mode = GET_MODE (tem);
2074 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2076 if (GET_CODE (x) == ZERO_EXTRACT)
2078 enum machine_mode new_mode
2079 = mode_for_extraction (EP_extzv, 1);
2080 if (new_mode != MAX_MACHINE_MODE)
2081 wanted_mode = new_mode;
2083 else if (GET_CODE (x) == SIGN_EXTRACT)
2085 enum machine_mode new_mode
2086 = mode_for_extraction (EP_extv, 1);
2087 if (new_mode != MAX_MACHINE_MODE)
2088 wanted_mode = new_mode;
2091 /* If we have a narrower mode, we can do something. */
2092 if (wanted_mode != VOIDmode
2093 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2095 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2096 rtx old_pos = XEXP (x, 2);
2099 /* If the bytes and bits are counted differently, we
2100 must adjust the offset. */
2101 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2102 offset = (GET_MODE_SIZE (is_mode)
2103 - GET_MODE_SIZE (wanted_mode) - offset);
2105 pos %= GET_MODE_BITSIZE (wanted_mode);
2107 newmem = adjust_address_nv (tem, wanted_mode, offset);
2109 /* Make the change and see if the insn remains valid. */
2110 INSN_CODE (insn) = -1;
2111 XEXP (x, 0) = newmem;
2112 XEXP (x, 2) = GEN_INT (pos);
2114 if (recog_memoized (insn) >= 0)
2117 /* Otherwise, restore old position. XEXP (x, 0) will be
2119 XEXP (x, 2) = old_pos;
2123 /* If we get here, the bitfield extract insn can't accept a memory
2124 reference. Copy the input into a register. */
2126 tem1 = gen_reg_rtx (GET_MODE (tem));
2127 emit_insn_before (gen_move_insn (tem1, tem), insn);
2134 if (SUBREG_REG (x) == var)
2136 /* If this is a special SUBREG made because VAR was promoted
2137 from a wider mode, replace it with VAR and call ourself
2138 recursively, this time saying that the object previously
2139 had its current mode (by virtue of the SUBREG). */
2141 if (SUBREG_PROMOTED_VAR_P (x))
2144 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements,
2149 /* If this SUBREG makes VAR wider, it has become a paradoxical
2150 SUBREG with VAR in memory, but these aren't allowed at this
2151 stage of the compilation. So load VAR into a pseudo and take
2152 a SUBREG of that pseudo. */
2153 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2155 replacement = find_fixup_replacement (replacements, var);
2156 if (replacement->new == 0)
2157 replacement->new = gen_reg_rtx (promoted_mode);
2158 SUBREG_REG (x) = replacement->new;
2162 /* See if we have already found a replacement for this SUBREG.
2163 If so, use it. Otherwise, make a MEM and see if the insn
2164 is recognized. If not, or if we should force MEM into a register,
2165 make a pseudo for this SUBREG. */
2166 replacement = find_fixup_replacement (replacements, x);
2167 if (replacement->new)
2169 *loc = replacement->new;
2173 replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
2175 INSN_CODE (insn) = -1;
2176 if (! flag_force_mem && recog_memoized (insn) >= 0)
2179 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2185 /* First do special simplification of bit-field references. */
2186 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2187 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2188 optimize_bit_field (x, insn, 0);
2189 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2190 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2191 optimize_bit_field (x, insn, 0);
2193 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2194 into a register and then store it back out. */
2195 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2196 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2197 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2198 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2199 > GET_MODE_SIZE (GET_MODE (var))))
2201 replacement = find_fixup_replacement (replacements, var);
2202 if (replacement->new == 0)
2203 replacement->new = gen_reg_rtx (GET_MODE (var));
2205 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2206 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2209 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2210 insn into a pseudo and store the low part of the pseudo into VAR. */
2211 if (GET_CODE (SET_DEST (x)) == SUBREG
2212 && SUBREG_REG (SET_DEST (x)) == var
2213 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2214 > GET_MODE_SIZE (GET_MODE (var))))
2216 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2217 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2224 rtx dest = SET_DEST (x);
2225 rtx src = SET_SRC (x);
2226 rtx outerdest = dest;
2228 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2229 || GET_CODE (dest) == SIGN_EXTRACT
2230 || GET_CODE (dest) == ZERO_EXTRACT)
2231 dest = XEXP (dest, 0);
2233 if (GET_CODE (src) == SUBREG)
2234 src = SUBREG_REG (src);
2236 /* If VAR does not appear at the top level of the SET
2237 just scan the lower levels of the tree. */
2239 if (src != var && dest != var)
2242 /* We will need to rerecognize this insn. */
2243 INSN_CODE (insn) = -1;
2245 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var
2246 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE)
2248 /* Since this case will return, ensure we fixup all the
2250 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2251 insn, replacements, no_share);
2252 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2253 insn, replacements, no_share);
2254 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2255 insn, replacements, no_share);
2257 tem = XEXP (outerdest, 0);
2259 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2260 that may appear inside a ZERO_EXTRACT.
2261 This was legitimate when the MEM was a REG. */
2262 if (GET_CODE (tem) == SUBREG
2263 && SUBREG_REG (tem) == var)
2264 tem = fixup_memory_subreg (tem, insn, 0);
2266 tem = fixup_stack_1 (tem, insn);
2268 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2269 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2270 && ! mode_dependent_address_p (XEXP (tem, 0))
2271 && ! MEM_VOLATILE_P (tem))
2273 enum machine_mode wanted_mode;
2274 enum machine_mode is_mode = GET_MODE (tem);
2275 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2277 wanted_mode = mode_for_extraction (EP_insv, 0);
2279 /* If we have a narrower mode, we can do something. */
2280 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2282 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2283 rtx old_pos = XEXP (outerdest, 2);
2286 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2287 offset = (GET_MODE_SIZE (is_mode)
2288 - GET_MODE_SIZE (wanted_mode) - offset);
2290 pos %= GET_MODE_BITSIZE (wanted_mode);
2292 newmem = adjust_address_nv (tem, wanted_mode, offset);
2294 /* Make the change and see if the insn remains valid. */
2295 INSN_CODE (insn) = -1;
2296 XEXP (outerdest, 0) = newmem;
2297 XEXP (outerdest, 2) = GEN_INT (pos);
2299 if (recog_memoized (insn) >= 0)
2302 /* Otherwise, restore old position. XEXP (x, 0) will be
2304 XEXP (outerdest, 2) = old_pos;
2308 /* If we get here, the bit-field store doesn't allow memory
2309 or isn't located at a constant position. Load the value into
2310 a register, do the store, and put it back into memory. */
2312 tem1 = gen_reg_rtx (GET_MODE (tem));
2313 emit_insn_before (gen_move_insn (tem1, tem), insn);
2314 emit_insn_after (gen_move_insn (tem, tem1), insn);
2315 XEXP (outerdest, 0) = tem1;
2319 /* STRICT_LOW_PART is a no-op on memory references
2320 and it can cause combinations to be unrecognizable,
2323 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2324 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2326 /* A valid insn to copy VAR into or out of a register
2327 must be left alone, to avoid an infinite loop here.
2328 If the reference to VAR is by a subreg, fix that up,
2329 since SUBREG is not valid for a memref.
2330 Also fix up the address of the stack slot.
2332 Note that we must not try to recognize the insn until
2333 after we know that we have valid addresses and no
2334 (subreg (mem ...) ...) constructs, since these interfere
2335 with determining the validity of the insn. */
2337 if ((SET_SRC (x) == var
2338 || (GET_CODE (SET_SRC (x)) == SUBREG
2339 && SUBREG_REG (SET_SRC (x)) == var))
2340 && (GET_CODE (SET_DEST (x)) == REG
2341 || (GET_CODE (SET_DEST (x)) == SUBREG
2342 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2343 && GET_MODE (var) == promoted_mode
2344 && x == single_set (insn))
2348 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2349 if (replacement->new)
2350 SET_SRC (x) = replacement->new;
2351 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2352 SET_SRC (x) = replacement->new
2353 = fixup_memory_subreg (SET_SRC (x), insn, 0);
2355 SET_SRC (x) = replacement->new
2356 = fixup_stack_1 (SET_SRC (x), insn);
2358 if (recog_memoized (insn) >= 0)
2361 /* INSN is not valid, but we know that we want to
2362 copy SET_SRC (x) to SET_DEST (x) in some way. So
2363 we generate the move and see whether it requires more
2364 than one insn. If it does, we emit those insns and
2365 delete INSN. Otherwise, we an just replace the pattern
2366 of INSN; we have already verified above that INSN has
2367 no other function that to do X. */
2369 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2370 if (GET_CODE (pat) == SEQUENCE)
2372 last = emit_insn_before (pat, insn);
2374 /* INSN might have REG_RETVAL or other important notes, so
2375 we need to store the pattern of the last insn in the
2376 sequence into INSN similarly to the normal case. LAST
2377 should not have REG_NOTES, but we allow them if INSN has
2379 if (REG_NOTES (last) && REG_NOTES (insn))
2381 if (REG_NOTES (last))
2382 REG_NOTES (insn) = REG_NOTES (last);
2383 PATTERN (insn) = PATTERN (last);
2388 PATTERN (insn) = pat;
2393 if ((SET_DEST (x) == var
2394 || (GET_CODE (SET_DEST (x)) == SUBREG
2395 && SUBREG_REG (SET_DEST (x)) == var))
2396 && (GET_CODE (SET_SRC (x)) == REG
2397 || (GET_CODE (SET_SRC (x)) == SUBREG
2398 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2399 && GET_MODE (var) == promoted_mode
2400 && x == single_set (insn))
2404 if (GET_CODE (SET_DEST (x)) == SUBREG)
2405 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
2407 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2409 if (recog_memoized (insn) >= 0)
2412 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2413 if (GET_CODE (pat) == SEQUENCE)
2415 last = emit_insn_before (pat, insn);
2417 /* INSN might have REG_RETVAL or other important notes, so
2418 we need to store the pattern of the last insn in the
2419 sequence into INSN similarly to the normal case. LAST
2420 should not have REG_NOTES, but we allow them if INSN has
2422 if (REG_NOTES (last) && REG_NOTES (insn))
2424 if (REG_NOTES (last))
2425 REG_NOTES (insn) = REG_NOTES (last);
2426 PATTERN (insn) = PATTERN (last);
2431 PATTERN (insn) = pat;
2436 /* Otherwise, storing into VAR must be handled specially
2437 by storing into a temporary and copying that into VAR
2438 with a new insn after this one. Note that this case
2439 will be used when storing into a promoted scalar since
2440 the insn will now have different modes on the input
2441 and output and hence will be invalid (except for the case
2442 of setting it to a constant, which does not need any
2443 change if it is valid). We generate extra code in that case,
2444 but combine.c will eliminate it. */
2449 rtx fixeddest = SET_DEST (x);
2451 /* STRICT_LOW_PART can be discarded, around a MEM. */
2452 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2453 fixeddest = XEXP (fixeddest, 0);
2454 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2455 if (GET_CODE (fixeddest) == SUBREG)
2457 fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
2458 promoted_mode = GET_MODE (fixeddest);
2461 fixeddest = fixup_stack_1 (fixeddest, insn);
2463 temp = gen_reg_rtx (promoted_mode);
2465 emit_insn_after (gen_move_insn (fixeddest,
2466 gen_lowpart (GET_MODE (fixeddest),
2470 SET_DEST (x) = temp;
2478 /* Nothing special about this RTX; fix its operands. */
2480 fmt = GET_RTX_FORMAT (code);
2481 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2484 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements,
2486 else if (fmt[i] == 'E')
2489 for (j = 0; j < XVECLEN (x, i); j++)
2490 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2491 insn, replacements, no_share);
2496 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2497 return an rtx (MEM:m1 newaddr) which is equivalent.
2498 If any insns must be emitted to compute NEWADDR, put them before INSN.
2500 UNCRITICAL nonzero means accept paradoxical subregs.
2501 This is used for subregs found inside REG_NOTES. */
2504 fixup_memory_subreg (x, insn, uncritical)
2509 int offset = SUBREG_BYTE (x);
2510 rtx addr = XEXP (SUBREG_REG (x), 0);
2511 enum machine_mode mode = GET_MODE (x);
2514 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2515 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
2519 if (!flag_force_addr
2520 && memory_address_p (mode, plus_constant (addr, offset)))
2521 /* Shortcut if no insns need be emitted. */
2522 return adjust_address (SUBREG_REG (x), mode, offset);
2525 result = adjust_address (SUBREG_REG (x), mode, offset);
2526 emit_insn_before (gen_sequence (), insn);
2531 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2532 Replace subexpressions of X in place.
2533 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2534 Otherwise return X, with its contents possibly altered.
2536 If any insns must be emitted to compute NEWADDR, put them before INSN.
2538 UNCRITICAL is as in fixup_memory_subreg. */
2541 walk_fixup_memory_subreg (x, insn, uncritical)
2553 code = GET_CODE (x);
2555 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2556 return fixup_memory_subreg (x, insn, uncritical);
2558 /* Nothing special about this RTX; fix its operands. */
2560 fmt = GET_RTX_FORMAT (code);
2561 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2564 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
2565 else if (fmt[i] == 'E')
2568 for (j = 0; j < XVECLEN (x, i); j++)
2570 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
2576 /* For each memory ref within X, if it refers to a stack slot
2577 with an out of range displacement, put the address in a temp register
2578 (emitting new insns before INSN to load these registers)
2579 and alter the memory ref to use that register.
2580 Replace each such MEM rtx with a copy, to avoid clobberage. */
2583 fixup_stack_1 (x, insn)
2588 RTX_CODE code = GET_CODE (x);
2593 rtx ad = XEXP (x, 0);
2594 /* If we have address of a stack slot but it's not valid
2595 (displacement is too large), compute the sum in a register. */
2596 if (GET_CODE (ad) == PLUS
2597 && GET_CODE (XEXP (ad, 0)) == REG
2598 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2599 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2600 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2601 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2602 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2604 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2605 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2606 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2607 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2610 if (memory_address_p (GET_MODE (x), ad))
2614 temp = copy_to_reg (ad);
2615 seq = gen_sequence ();
2617 emit_insn_before (seq, insn);
2618 return replace_equiv_address (x, temp);
2623 fmt = GET_RTX_FORMAT (code);
2624 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2627 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2628 else if (fmt[i] == 'E')
2631 for (j = 0; j < XVECLEN (x, i); j++)
2632 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2638 /* Optimization: a bit-field instruction whose field
2639 happens to be a byte or halfword in memory
2640 can be changed to a move instruction.
2642 We call here when INSN is an insn to examine or store into a bit-field.
2643 BODY is the SET-rtx to be altered.
2645 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2646 (Currently this is called only from function.c, and EQUIV_MEM
2650 optimize_bit_field (body, insn, equiv_mem)
2658 enum machine_mode mode;
2660 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2661 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2662 bitfield = SET_DEST (body), destflag = 1;
2664 bitfield = SET_SRC (body), destflag = 0;
2666 /* First check that the field being stored has constant size and position
2667 and is in fact a byte or halfword suitably aligned. */
2669 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2670 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2671 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2673 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2677 /* Now check that the containing word is memory, not a register,
2678 and that it is safe to change the machine mode. */
2680 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2681 memref = XEXP (bitfield, 0);
2682 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2684 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2685 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2686 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2687 memref = SUBREG_REG (XEXP (bitfield, 0));
2688 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2690 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2691 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2694 && ! mode_dependent_address_p (XEXP (memref, 0))
2695 && ! MEM_VOLATILE_P (memref))
2697 /* Now adjust the address, first for any subreg'ing
2698 that we are now getting rid of,
2699 and then for which byte of the word is wanted. */
2701 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2704 /* Adjust OFFSET to count bits from low-address byte. */
2705 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2706 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2707 - offset - INTVAL (XEXP (bitfield, 1)));
2709 /* Adjust OFFSET to count bytes from low-address byte. */
2710 offset /= BITS_PER_UNIT;
2711 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2713 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2714 / UNITS_PER_WORD) * UNITS_PER_WORD;
2715 if (BYTES_BIG_ENDIAN)
2716 offset -= (MIN (UNITS_PER_WORD,
2717 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2718 - MIN (UNITS_PER_WORD,
2719 GET_MODE_SIZE (GET_MODE (memref))));
2723 memref = adjust_address (memref, mode, offset);
2724 insns = get_insns ();
2726 emit_insns_before (insns, insn);
2728 /* Store this memory reference where
2729 we found the bit field reference. */
2733 validate_change (insn, &SET_DEST (body), memref, 1);
2734 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2736 rtx src = SET_SRC (body);
2737 while (GET_CODE (src) == SUBREG
2738 && SUBREG_BYTE (src) == 0)
2739 src = SUBREG_REG (src);
2740 if (GET_MODE (src) != GET_MODE (memref))
2741 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2742 validate_change (insn, &SET_SRC (body), src, 1);
2744 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2745 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2746 /* This shouldn't happen because anything that didn't have
2747 one of these modes should have got converted explicitly
2748 and then referenced through a subreg.
2749 This is so because the original bit-field was
2750 handled by agg_mode and so its tree structure had
2751 the same mode that memref now has. */
2756 rtx dest = SET_DEST (body);
2758 while (GET_CODE (dest) == SUBREG
2759 && SUBREG_BYTE (dest) == 0
2760 && (GET_MODE_CLASS (GET_MODE (dest))
2761 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2762 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2764 dest = SUBREG_REG (dest);
2766 validate_change (insn, &SET_DEST (body), dest, 1);
2768 if (GET_MODE (dest) == GET_MODE (memref))
2769 validate_change (insn, &SET_SRC (body), memref, 1);
2772 /* Convert the mem ref to the destination mode. */
2773 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2776 convert_move (newreg, memref,
2777 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2781 validate_change (insn, &SET_SRC (body), newreg, 1);
2785 /* See if we can convert this extraction or insertion into
2786 a simple move insn. We might not be able to do so if this
2787 was, for example, part of a PARALLEL.
2789 If we succeed, write out any needed conversions. If we fail,
2790 it is hard to guess why we failed, so don't do anything
2791 special; just let the optimization be suppressed. */
2793 if (apply_change_group () && seq)
2794 emit_insns_before (seq, insn);
2799 /* These routines are responsible for converting virtual register references
2800 to the actual hard register references once RTL generation is complete.
2802 The following four variables are used for communication between the
2803 routines. They contain the offsets of the virtual registers from their
2804 respective hard registers. */
2806 static int in_arg_offset;
2807 static int var_offset;
2808 static int dynamic_offset;
2809 static int out_arg_offset;
2810 static int cfa_offset;
2812 /* In most machines, the stack pointer register is equivalent to the bottom
2815 #ifndef STACK_POINTER_OFFSET
2816 #define STACK_POINTER_OFFSET 0
2819 /* If not defined, pick an appropriate default for the offset of dynamically
2820 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2821 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2823 #ifndef STACK_DYNAMIC_OFFSET
2825 /* The bottom of the stack points to the actual arguments. If
2826 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2827 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2828 stack space for register parameters is not pushed by the caller, but
2829 rather part of the fixed stack areas and hence not included in
2830 `current_function_outgoing_args_size'. Nevertheless, we must allow
2831 for it when allocating stack dynamic objects. */
2833 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2834 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2835 ((ACCUMULATE_OUTGOING_ARGS \
2836 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2837 + (STACK_POINTER_OFFSET)) \
2840 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2841 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2842 + (STACK_POINTER_OFFSET))
2846 /* On most machines, the CFA coincides with the first incoming parm. */
2848 #ifndef ARG_POINTER_CFA_OFFSET
2849 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2852 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had its
2853 address taken. DECL is the decl or SAVE_EXPR for the object stored in the
2854 register, for later use if we do need to force REG into the stack. REG is
2855 overwritten by the MEM like in put_reg_into_stack. */
2858 gen_mem_addressof (reg, decl)
2862 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2865 /* Calculate this before we start messing with decl's RTL. */
2866 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0;
2868 /* If the original REG was a user-variable, then so is the REG whose
2869 address is being taken. Likewise for unchanging. */
2870 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2871 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2873 PUT_CODE (reg, MEM);
2874 MEM_ATTRS (reg) = 0;
2879 tree type = TREE_TYPE (decl);
2880 enum machine_mode decl_mode
2881 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl)));
2882 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl)
2883 : DECL_RTL_IF_SET (decl));
2885 PUT_MODE (reg, decl_mode);
2887 /* Clear DECL_RTL momentarily so functions below will work
2888 properly, then set it again. */
2889 if (DECL_P (decl) && decl_rtl == reg)
2890 SET_DECL_RTL (decl, 0);
2892 set_mem_attributes (reg, decl, 1);
2893 set_mem_alias_set (reg, set);
2895 if (DECL_P (decl) && decl_rtl == reg)
2896 SET_DECL_RTL (decl, reg);
2898 if (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0))
2899 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), reg, 0);
2902 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0);
2907 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2910 flush_addressof (decl)
2913 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2914 && DECL_RTL (decl) != 0
2915 && GET_CODE (DECL_RTL (decl)) == MEM
2916 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2917 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2918 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2921 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2924 put_addressof_into_stack (r, ht)
2926 struct hash_table *ht;
2929 int volatile_p, used_p;
2931 rtx reg = XEXP (r, 0);
2933 if (GET_CODE (reg) != REG)
2936 decl = ADDRESSOF_DECL (r);
2939 type = TREE_TYPE (decl);
2940 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2941 && TREE_THIS_VOLATILE (decl));
2942 used_p = (TREE_USED (decl)
2943 || (DECL_P (decl) && DECL_INITIAL (decl) != 0));
2952 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2953 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2956 /* List of replacements made below in purge_addressof_1 when creating
2957 bitfield insertions. */
2958 static rtx purge_bitfield_addressof_replacements;
2960 /* List of replacements made below in purge_addressof_1 for patterns
2961 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2962 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2963 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2964 enough in complex cases, e.g. when some field values can be
2965 extracted by usage MEM with narrower mode. */
2966 static rtx purge_addressof_replacements;
2968 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2969 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2970 the stack. If the function returns FALSE then the replacement could not
2974 purge_addressof_1 (loc, insn, force, store, ht)
2978 struct hash_table *ht;
2986 /* Re-start here to avoid recursion in common cases. */
2993 code = GET_CODE (x);
2995 /* If we don't return in any of the cases below, we will recurse inside
2996 the RTX, which will normally result in any ADDRESSOF being forced into
3000 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
3001 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
3004 else if (code == ADDRESSOF)
3008 if (GET_CODE (XEXP (x, 0)) != MEM)
3010 put_addressof_into_stack (x, ht);
3014 /* We must create a copy of the rtx because it was created by
3015 overwriting a REG rtx which is always shared. */
3016 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
3017 if (validate_change (insn, loc, sub, 0)
3018 || validate_replace_rtx (x, sub, insn))
3022 sub = force_operand (sub, NULL_RTX);
3023 if (! validate_change (insn, loc, sub, 0)
3024 && ! validate_replace_rtx (x, sub, insn))
3027 insns = gen_sequence ();
3029 emit_insn_before (insns, insn);
3033 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3035 rtx sub = XEXP (XEXP (x, 0), 0);
3037 if (GET_CODE (sub) == MEM)
3038 sub = adjust_address_nv (sub, GET_MODE (x), 0);
3039 else if (GET_CODE (sub) == REG
3040 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3042 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3044 int size_x, size_sub;
3048 /* When processing REG_NOTES look at the list of
3049 replacements done on the insn to find the register that X
3053 for (tem = purge_bitfield_addressof_replacements;
3055 tem = XEXP (XEXP (tem, 1), 1))
3056 if (rtx_equal_p (x, XEXP (tem, 0)))
3058 *loc = XEXP (XEXP (tem, 1), 0);
3062 /* See comment for purge_addressof_replacements. */
3063 for (tem = purge_addressof_replacements;
3065 tem = XEXP (XEXP (tem, 1), 1))
3066 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3068 rtx z = XEXP (XEXP (tem, 1), 0);
3070 if (GET_MODE (x) == GET_MODE (z)
3071 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3072 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3075 /* It can happen that the note may speak of things
3076 in a wider (or just different) mode than the
3077 code did. This is especially true of
3080 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3083 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3084 && (GET_MODE_SIZE (GET_MODE (x))
3085 > GET_MODE_SIZE (GET_MODE (z))))
3087 /* This can occur as a result in invalid
3088 pointer casts, e.g. float f; ...
3089 *(long long int *)&f.
3090 ??? We could emit a warning here, but
3091 without a line number that wouldn't be
3093 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3096 z = gen_lowpart (GET_MODE (x), z);
3102 /* Sometimes we may not be able to find the replacement. For
3103 example when the original insn was a MEM in a wider mode,
3104 and the note is part of a sign extension of a narrowed
3105 version of that MEM. Gcc testcase compile/990829-1.c can
3106 generate an example of this situation. Rather than complain
3107 we return false, which will prompt our caller to remove the
3112 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3113 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3115 /* Don't even consider working with paradoxical subregs,
3116 or the moral equivalent seen here. */
3117 if (size_x <= size_sub
3118 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3120 /* Do a bitfield insertion to mirror what would happen
3127 rtx p = PREV_INSN (insn);
3130 val = gen_reg_rtx (GET_MODE (x));
3131 if (! validate_change (insn, loc, val, 0))
3133 /* Discard the current sequence and put the
3134 ADDRESSOF on stack. */
3138 seq = gen_sequence ();
3140 emit_insn_before (seq, insn);
3141 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3145 store_bit_field (sub, size_x, 0, GET_MODE (x),
3146 val, GET_MODE_SIZE (GET_MODE (sub)));
3148 /* Make sure to unshare any shared rtl that store_bit_field
3149 might have created. */
3150 unshare_all_rtl_again (get_insns ());
3152 seq = gen_sequence ();
3154 p = emit_insn_after (seq, insn);
3155 if (NEXT_INSN (insn))
3156 compute_insns_for_mem (NEXT_INSN (insn),
3157 p ? NEXT_INSN (p) : NULL_RTX,
3162 rtx p = PREV_INSN (insn);
3165 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3166 GET_MODE (x), GET_MODE (x),
3167 GET_MODE_SIZE (GET_MODE (sub)));
3169 if (! validate_change (insn, loc, val, 0))
3171 /* Discard the current sequence and put the
3172 ADDRESSOF on stack. */
3177 seq = gen_sequence ();
3179 emit_insn_before (seq, insn);
3180 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3184 /* Remember the replacement so that the same one can be done
3185 on the REG_NOTES. */
3186 purge_bitfield_addressof_replacements
3187 = gen_rtx_EXPR_LIST (VOIDmode, x,
3190 purge_bitfield_addressof_replacements));
3192 /* We replaced with a reg -- all done. */
3197 else if (validate_change (insn, loc, sub, 0))
3199 /* Remember the replacement so that the same one can be done
3200 on the REG_NOTES. */
3201 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3205 for (tem = purge_addressof_replacements;
3207 tem = XEXP (XEXP (tem, 1), 1))
3208 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3210 XEXP (XEXP (tem, 1), 0) = sub;
3213 purge_addressof_replacements
3214 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3215 gen_rtx_EXPR_LIST (VOIDmode, sub,
3216 purge_addressof_replacements));
3224 /* Scan all subexpressions. */
3225 fmt = GET_RTX_FORMAT (code);
3226 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3229 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0, ht);
3230 else if (*fmt == 'E')
3231 for (j = 0; j < XVECLEN (x, i); j++)
3232 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, ht);
3238 /* Return a new hash table entry in HT. */
3240 static struct hash_entry *
3241 insns_for_mem_newfunc (he, ht, k)
3242 struct hash_entry *he;
3243 struct hash_table *ht;
3244 hash_table_key k ATTRIBUTE_UNUSED;
3246 struct insns_for_mem_entry *ifmhe;
3250 ifmhe = ((struct insns_for_mem_entry *)
3251 hash_allocate (ht, sizeof (struct insns_for_mem_entry)));
3252 ifmhe->insns = NULL_RTX;
3257 /* Return a hash value for K, a REG. */
3259 static unsigned long
3260 insns_for_mem_hash (k)
3263 /* K is really a RTX. Just use the address as the hash value. */
3264 return (unsigned long) k;
3267 /* Return non-zero if K1 and K2 (two REGs) are the same. */
3270 insns_for_mem_comp (k1, k2)
3277 struct insns_for_mem_walk_info
3279 /* The hash table that we are using to record which INSNs use which
3281 struct hash_table *ht;
3283 /* The INSN we are currently processing. */
3286 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3287 to find the insns that use the REGs in the ADDRESSOFs. */
3291 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3292 that might be used in an ADDRESSOF expression, record this INSN in
3293 the hash table given by DATA (which is really a pointer to an
3294 insns_for_mem_walk_info structure). */
3297 insns_for_mem_walk (r, data)
3301 struct insns_for_mem_walk_info *ifmwi
3302 = (struct insns_for_mem_walk_info *) data;
3304 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3305 && GET_CODE (XEXP (*r, 0)) == REG)
3306 hash_lookup (ifmwi->ht, XEXP (*r, 0), /*create=*/1, /*copy=*/0);
3307 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3309 /* Lookup this MEM in the hashtable, creating it if necessary. */
3310 struct insns_for_mem_entry *ifme
3311 = (struct insns_for_mem_entry *) hash_lookup (ifmwi->ht,
3316 /* If we have not already recorded this INSN, do so now. Since
3317 we process the INSNs in order, we know that if we have
3318 recorded it it must be at the front of the list. */
3319 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3320 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3327 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3328 which REGs in HT. */
3331 compute_insns_for_mem (insns, last_insn, ht)
3334 struct hash_table *ht;
3337 struct insns_for_mem_walk_info ifmwi;
3340 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3341 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3345 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3349 /* Helper function for purge_addressof called through for_each_rtx.
3350 Returns true iff the rtl is an ADDRESSOF. */
3353 is_addressof (rtl, data)
3355 void *data ATTRIBUTE_UNUSED;
3357 return GET_CODE (*rtl) == ADDRESSOF;
3360 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3361 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3365 purge_addressof (insns)
3369 struct hash_table ht;
3371 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3372 requires a fixup pass over the instruction stream to correct
3373 INSNs that depended on the REG being a REG, and not a MEM. But,
3374 these fixup passes are slow. Furthermore, most MEMs are not
3375 mentioned in very many instructions. So, we speed up the process
3376 by pre-calculating which REGs occur in which INSNs; that allows
3377 us to perform the fixup passes much more quickly. */
3378 hash_table_init (&ht,
3379 insns_for_mem_newfunc,
3381 insns_for_mem_comp);
3382 compute_insns_for_mem (insns, NULL_RTX, &ht);
3384 for (insn = insns; insn; insn = NEXT_INSN (insn))
3385 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3386 || GET_CODE (insn) == CALL_INSN)
3388 if (! purge_addressof_1 (&PATTERN (insn), insn,
3389 asm_noperands (PATTERN (insn)) > 0, 0, &ht))
3390 /* If we could not replace the ADDRESSOFs in the insn,
3391 something is wrong. */
3394 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, &ht))
3396 /* If we could not replace the ADDRESSOFs in the insn's notes,
3397 we can just remove the offending notes instead. */
3400 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3402 /* If we find a REG_RETVAL note then the insn is a libcall.
3403 Such insns must have REG_EQUAL notes as well, in order
3404 for later passes of the compiler to work. So it is not
3405 safe to delete the notes here, and instead we abort. */
3406 if (REG_NOTE_KIND (note) == REG_RETVAL)
3408 if (for_each_rtx (¬e, is_addressof, NULL))
3409 remove_note (insn, note);
3415 hash_table_free (&ht);
3416 purge_bitfield_addressof_replacements = 0;
3417 purge_addressof_replacements = 0;
3419 /* REGs are shared. purge_addressof will destructively replace a REG
3420 with a MEM, which creates shared MEMs.
3422 Unfortunately, the children of put_reg_into_stack assume that MEMs
3423 referring to the same stack slot are shared (fixup_var_refs and
3424 the associated hash table code).
3426 So, we have to do another unsharing pass after we have flushed any
3427 REGs that had their address taken into the stack.
3429 It may be worth tracking whether or not we converted any REGs into
3430 MEMs to avoid this overhead when it is not needed. */
3431 unshare_all_rtl_again (get_insns ());
3434 /* Convert a SET of a hard subreg to a set of the appropriate hard
3435 register. A subroutine of purge_hard_subreg_sets. */
3438 purge_single_hard_subreg_set (pattern)
3441 rtx reg = SET_DEST (pattern);
3442 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3445 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3446 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3448 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3449 GET_MODE (SUBREG_REG (reg)),
3452 reg = SUBREG_REG (reg);
3456 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3458 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3459 SET_DEST (pattern) = reg;
3463 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3464 only such SETs that we expect to see are those left in because
3465 integrate can't handle sets of parts of a return value register.
3467 We don't use alter_subreg because we only want to eliminate subregs
3468 of hard registers. */
3471 purge_hard_subreg_sets (insn)
3474 for (; insn; insn = NEXT_INSN (insn))
3478 rtx pattern = PATTERN (insn);
3479 switch (GET_CODE (pattern))
3482 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3483 purge_single_hard_subreg_set (pattern);
3488 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3490 rtx inner_pattern = XVECEXP (pattern, 0, j);
3491 if (GET_CODE (inner_pattern) == SET
3492 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3493 purge_single_hard_subreg_set (inner_pattern);
3504 /* Pass through the INSNS of function FNDECL and convert virtual register
3505 references to hard register references. */
3508 instantiate_virtual_regs (fndecl, insns)
3515 /* Compute the offsets to use for this function. */
3516 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3517 var_offset = STARTING_FRAME_OFFSET;
3518 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3519 out_arg_offset = STACK_POINTER_OFFSET;
3520 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3522 /* Scan all variables and parameters of this function. For each that is
3523 in memory, instantiate all virtual registers if the result is a valid
3524 address. If not, we do it later. That will handle most uses of virtual
3525 regs on many machines. */
3526 instantiate_decls (fndecl, 1);
3528 /* Initialize recognition, indicating that volatile is OK. */
3531 /* Scan through all the insns, instantiating every virtual register still
3533 for (insn = insns; insn; insn = NEXT_INSN (insn))
3534 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3535 || GET_CODE (insn) == CALL_INSN)
3537 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3538 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3539 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3540 if (GET_CODE (insn) == CALL_INSN)
3541 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3545 /* Instantiate the stack slots for the parm registers, for later use in
3546 addressof elimination. */
3547 for (i = 0; i < max_parm_reg; ++i)
3548 if (parm_reg_stack_loc[i])
3549 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3551 /* Now instantiate the remaining register equivalences for debugging info.
3552 These will not be valid addresses. */
3553 instantiate_decls (fndecl, 0);
3555 /* Indicate that, from now on, assign_stack_local should use
3556 frame_pointer_rtx. */
3557 virtuals_instantiated = 1;
3560 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3561 all virtual registers in their DECL_RTL's.
3563 If VALID_ONLY, do this only if the resulting address is still valid.
3564 Otherwise, always do it. */
3567 instantiate_decls (fndecl, valid_only)
3573 /* Process all parameters of the function. */
3574 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3576 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3577 HOST_WIDE_INT size_rtl;
3579 instantiate_decl (DECL_RTL (decl), size, valid_only);
3581 /* If the parameter was promoted, then the incoming RTL mode may be
3582 larger than the declared type size. We must use the larger of
3584 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3585 size = MAX (size_rtl, size);
3586 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3589 /* Now process all variables defined in the function or its subblocks. */
3590 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3593 /* Subroutine of instantiate_decls: Process all decls in the given
3594 BLOCK node and all its subblocks. */
3597 instantiate_decls_1 (let, valid_only)
3603 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3604 if (DECL_RTL_SET_P (t))
3605 instantiate_decl (DECL_RTL (t),
3606 int_size_in_bytes (TREE_TYPE (t)),
3609 /* Process all subblocks. */
3610 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3611 instantiate_decls_1 (t, valid_only);
3614 /* Subroutine of the preceding procedures: Given RTL representing a
3615 decl and the size of the object, do any instantiation required.
3617 If VALID_ONLY is non-zero, it means that the RTL should only be
3618 changed if the new address is valid. */
3621 instantiate_decl (x, size, valid_only)
3626 enum machine_mode mode;
3629 /* If this is not a MEM, no need to do anything. Similarly if the
3630 address is a constant or a register that is not a virtual register. */
3632 if (x == 0 || GET_CODE (x) != MEM)
3636 if (CONSTANT_P (addr)
3637 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3638 || (GET_CODE (addr) == REG
3639 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3640 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3643 /* If we should only do this if the address is valid, copy the address.
3644 We need to do this so we can undo any changes that might make the
3645 address invalid. This copy is unfortunate, but probably can't be
3649 addr = copy_rtx (addr);
3651 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3653 if (valid_only && size >= 0)
3655 unsigned HOST_WIDE_INT decl_size = size;
3657 /* Now verify that the resulting address is valid for every integer or
3658 floating-point mode up to and including SIZE bytes long. We do this
3659 since the object might be accessed in any mode and frame addresses
3662 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3663 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3664 mode = GET_MODE_WIDER_MODE (mode))
3665 if (! memory_address_p (mode, addr))
3668 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3669 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3670 mode = GET_MODE_WIDER_MODE (mode))
3671 if (! memory_address_p (mode, addr))
3675 /* Put back the address now that we have updated it and we either know
3676 it is valid or we don't care whether it is valid. */
3681 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3682 is a virtual register, return the equivalent hard register and set the
3683 offset indirectly through the pointer. Otherwise, return 0. */
3686 instantiate_new_reg (x, poffset)
3688 HOST_WIDE_INT *poffset;
3691 HOST_WIDE_INT offset;
3693 if (x == virtual_incoming_args_rtx)
3694 new = arg_pointer_rtx, offset = in_arg_offset;
3695 else if (x == virtual_stack_vars_rtx)
3696 new = frame_pointer_rtx, offset = var_offset;
3697 else if (x == virtual_stack_dynamic_rtx)
3698 new = stack_pointer_rtx, offset = dynamic_offset;
3699 else if (x == virtual_outgoing_args_rtx)
3700 new = stack_pointer_rtx, offset = out_arg_offset;
3701 else if (x == virtual_cfa_rtx)
3702 new = arg_pointer_rtx, offset = cfa_offset;
3710 /* Given a pointer to a piece of rtx and an optional pointer to the
3711 containing object, instantiate any virtual registers present in it.
3713 If EXTRA_INSNS, we always do the replacement and generate
3714 any extra insns before OBJECT. If it zero, we do nothing if replacement
3717 Return 1 if we either had nothing to do or if we were able to do the
3718 needed replacement. Return 0 otherwise; we only return zero if
3719 EXTRA_INSNS is zero.
3721 We first try some simple transformations to avoid the creation of extra
3725 instantiate_virtual_regs_1 (loc, object, extra_insns)
3733 HOST_WIDE_INT offset = 0;
3739 /* Re-start here to avoid recursion in common cases. */
3746 code = GET_CODE (x);
3748 /* Check for some special cases. */
3766 /* We are allowed to set the virtual registers. This means that
3767 the actual register should receive the source minus the
3768 appropriate offset. This is used, for example, in the handling
3769 of non-local gotos. */
3770 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3772 rtx src = SET_SRC (x);
3774 /* We are setting the register, not using it, so the relevant
3775 offset is the negative of the offset to use were we using
3778 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3780 /* The only valid sources here are PLUS or REG. Just do
3781 the simplest possible thing to handle them. */
3782 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3786 if (GET_CODE (src) != REG)
3787 temp = force_operand (src, NULL_RTX);
3790 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3794 emit_insns_before (seq, object);
3797 if (! validate_change (object, &SET_SRC (x), temp, 0)
3804 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3809 /* Handle special case of virtual register plus constant. */
3810 if (CONSTANT_P (XEXP (x, 1)))
3812 rtx old, new_offset;
3814 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3815 if (GET_CODE (XEXP (x, 0)) == PLUS)
3817 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3819 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3821 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3830 #ifdef POINTERS_EXTEND_UNSIGNED
3831 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3832 we can commute the PLUS and SUBREG because pointers into the
3833 frame are well-behaved. */
3834 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3835 && GET_CODE (XEXP (x, 1)) == CONST_INT
3837 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3839 && validate_change (object, loc,
3840 plus_constant (gen_lowpart (ptr_mode,
3843 + INTVAL (XEXP (x, 1))),
3847 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3849 /* We know the second operand is a constant. Unless the
3850 first operand is a REG (which has been already checked),
3851 it needs to be checked. */
3852 if (GET_CODE (XEXP (x, 0)) != REG)
3860 new_offset = plus_constant (XEXP (x, 1), offset);
3862 /* If the new constant is zero, try to replace the sum with just
3864 if (new_offset == const0_rtx
3865 && validate_change (object, loc, new, 0))
3868 /* Next try to replace the register and new offset.
3869 There are two changes to validate here and we can't assume that
3870 in the case of old offset equals new just changing the register
3871 will yield a valid insn. In the interests of a little efficiency,
3872 however, we only call validate change once (we don't queue up the
3873 changes and then call apply_change_group). */
3877 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3878 : (XEXP (x, 0) = new,
3879 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3887 /* Otherwise copy the new constant into a register and replace
3888 constant with that register. */
3889 temp = gen_reg_rtx (Pmode);
3891 if (validate_change (object, &XEXP (x, 1), temp, 0))
3892 emit_insn_before (gen_move_insn (temp, new_offset), object);
3895 /* If that didn't work, replace this expression with a
3896 register containing the sum. */
3899 new = gen_rtx_PLUS (Pmode, new, new_offset);
3902 temp = force_operand (new, NULL_RTX);
3906 emit_insns_before (seq, object);
3907 if (! validate_change (object, loc, temp, 0)
3908 && ! validate_replace_rtx (x, temp, object))
3916 /* Fall through to generic two-operand expression case. */
3922 case DIV: case UDIV:
3923 case MOD: case UMOD:
3924 case AND: case IOR: case XOR:
3925 case ROTATERT: case ROTATE:
3926 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3928 case GE: case GT: case GEU: case GTU:
3929 case LE: case LT: case LEU: case LTU:
3930 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3931 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3936 /* Most cases of MEM that convert to valid addresses have already been
3937 handled by our scan of decls. The only special handling we
3938 need here is to make a copy of the rtx to ensure it isn't being
3939 shared if we have to change it to a pseudo.
3941 If the rtx is a simple reference to an address via a virtual register,
3942 it can potentially be shared. In such cases, first try to make it
3943 a valid address, which can also be shared. Otherwise, copy it and
3946 First check for common cases that need no processing. These are
3947 usually due to instantiation already being done on a previous instance
3951 if (CONSTANT_ADDRESS_P (temp)
3952 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3953 || temp == arg_pointer_rtx
3955 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3956 || temp == hard_frame_pointer_rtx
3958 || temp == frame_pointer_rtx)
3961 if (GET_CODE (temp) == PLUS
3962 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3963 && (XEXP (temp, 0) == frame_pointer_rtx
3964 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3965 || XEXP (temp, 0) == hard_frame_pointer_rtx
3967 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3968 || XEXP (temp, 0) == arg_pointer_rtx
3973 if (temp == virtual_stack_vars_rtx
3974 || temp == virtual_incoming_args_rtx
3975 || (GET_CODE (temp) == PLUS
3976 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3977 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3978 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3980 /* This MEM may be shared. If the substitution can be done without
3981 the need to generate new pseudos, we want to do it in place
3982 so all copies of the shared rtx benefit. The call below will
3983 only make substitutions if the resulting address is still
3986 Note that we cannot pass X as the object in the recursive call
3987 since the insn being processed may not allow all valid
3988 addresses. However, if we were not passed on object, we can
3989 only modify X without copying it if X will have a valid
3992 ??? Also note that this can still lose if OBJECT is an insn that
3993 has less restrictions on an address that some other insn.
3994 In that case, we will modify the shared address. This case
3995 doesn't seem very likely, though. One case where this could
3996 happen is in the case of a USE or CLOBBER reference, but we
3997 take care of that below. */
3999 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
4000 object ? object : x, 0))
4003 /* Otherwise make a copy and process that copy. We copy the entire
4004 RTL expression since it might be a PLUS which could also be
4006 *loc = x = copy_rtx (x);
4009 /* Fall through to generic unary operation case. */
4012 case STRICT_LOW_PART:
4014 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4015 case SIGN_EXTEND: case ZERO_EXTEND:
4016 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4017 case FLOAT: case FIX:
4018 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4022 /* These case either have just one operand or we know that we need not
4023 check the rest of the operands. */
4029 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4030 go ahead and make the invalid one, but do it to a copy. For a REG,
4031 just make the recursive call, since there's no chance of a problem. */
4033 if ((GET_CODE (XEXP (x, 0)) == MEM
4034 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4036 || (GET_CODE (XEXP (x, 0)) == REG
4037 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4040 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4045 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4046 in front of this insn and substitute the temporary. */
4047 if ((new = instantiate_new_reg (x, &offset)) != 0)
4049 temp = plus_constant (new, offset);
4050 if (!validate_change (object, loc, temp, 0))
4056 temp = force_operand (temp, NULL_RTX);
4060 emit_insns_before (seq, object);
4061 if (! validate_change (object, loc, temp, 0)
4062 && ! validate_replace_rtx (x, temp, object))
4070 if (GET_CODE (XEXP (x, 0)) == REG)
4073 else if (GET_CODE (XEXP (x, 0)) == MEM)
4075 /* If we have a (addressof (mem ..)), do any instantiation inside
4076 since we know we'll be making the inside valid when we finally
4077 remove the ADDRESSOF. */
4078 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4087 /* Scan all subexpressions. */
4088 fmt = GET_RTX_FORMAT (code);
4089 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4092 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4095 else if (*fmt == 'E')
4096 for (j = 0; j < XVECLEN (x, i); j++)
4097 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4104 /* Optimization: assuming this function does not receive nonlocal gotos,
4105 delete the handlers for such, as well as the insns to establish
4106 and disestablish them. */
4112 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4114 /* Delete the handler by turning off the flag that would
4115 prevent jump_optimize from deleting it.
4116 Also permit deletion of the nonlocal labels themselves
4117 if nothing local refers to them. */
4118 if (GET_CODE (insn) == CODE_LABEL)
4122 LABEL_PRESERVE_P (insn) = 0;
4124 /* Remove it from the nonlocal_label list, to avoid confusing
4126 for (t = nonlocal_labels, last_t = 0; t;
4127 last_t = t, t = TREE_CHAIN (t))
4128 if (DECL_RTL (TREE_VALUE (t)) == insn)
4133 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4135 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4138 if (GET_CODE (insn) == INSN)
4142 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4143 if (reg_mentioned_p (t, PATTERN (insn)))
4149 || (nonlocal_goto_stack_level != 0
4150 && reg_mentioned_p (nonlocal_goto_stack_level,
4152 delete_related_insns (insn);
4160 return max_parm_reg;
4163 /* Return the first insn following those generated by `assign_parms'. */
4166 get_first_nonparm_insn ()
4169 return NEXT_INSN (last_parm_insn);
4170 return get_insns ();
4173 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
4174 Crash if there is none. */
4177 get_first_block_beg ()
4180 rtx insn = get_first_nonparm_insn ();
4182 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
4183 if (GET_CODE (searcher) == NOTE
4184 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
4187 abort (); /* Invalid call to this function. (See comments above.) */
4191 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4192 This means a type for which function calls must pass an address to the
4193 function or get an address back from the function.
4194 EXP may be a type node or an expression (whose type is tested). */
4197 aggregate_value_p (exp)
4200 int i, regno, nregs;
4203 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4205 if (TREE_CODE (type) == VOID_TYPE)
4207 if (RETURN_IN_MEMORY (type))
4209 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4210 and thus can't be returned in registers. */
4211 if (TREE_ADDRESSABLE (type))
4213 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4215 /* Make sure we have suitable call-clobbered regs to return
4216 the value in; if not, we must return it in memory. */
4217 reg = hard_function_value (type, 0, 0);
4219 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4221 if (GET_CODE (reg) != REG)
4224 regno = REGNO (reg);
4225 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4226 for (i = 0; i < nregs; i++)
4227 if (! call_used_regs[regno + i])
4232 /* Assign RTL expressions to the function's parameters.
4233 This may involve copying them into registers and using
4234 those registers as the RTL for them. */
4237 assign_parms (fndecl)
4243 CUMULATIVE_ARGS args_so_far;
4244 enum machine_mode promoted_mode, passed_mode;
4245 enum machine_mode nominal_mode, promoted_nominal_mode;
4247 /* Total space needed so far for args on the stack,
4248 given as a constant and a tree-expression. */
4249 struct args_size stack_args_size;
4250 tree fntype = TREE_TYPE (fndecl);
4251 tree fnargs = DECL_ARGUMENTS (fndecl);
4252 /* This is used for the arg pointer when referring to stack args. */
4253 rtx internal_arg_pointer;
4254 /* This is a dummy PARM_DECL that we used for the function result if
4255 the function returns a structure. */
4256 tree function_result_decl = 0;
4257 #ifdef SETUP_INCOMING_VARARGS
4258 int varargs_setup = 0;
4260 rtx conversion_insns = 0;
4261 struct args_size alignment_pad;
4263 /* Nonzero if the last arg is named `__builtin_va_alist',
4264 which is used on some machines for old-fashioned non-ANSI varargs.h;
4265 this should be stuck onto the stack as if it had arrived there. */
4267 = (current_function_varargs
4269 && (parm = tree_last (fnargs)) != 0
4271 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
4272 "__builtin_va_alist")));
4274 /* Nonzero if function takes extra anonymous args.
4275 This means the last named arg must be on the stack
4276 right before the anonymous ones. */
4278 = (TYPE_ARG_TYPES (fntype) != 0
4279 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4280 != void_type_node));
4282 current_function_stdarg = stdarg;
4284 /* If the reg that the virtual arg pointer will be translated into is
4285 not a fixed reg or is the stack pointer, make a copy of the virtual
4286 arg pointer, and address parms via the copy. The frame pointer is
4287 considered fixed even though it is not marked as such.
4289 The second time through, simply use ap to avoid generating rtx. */
4291 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4292 || ! (fixed_regs[ARG_POINTER_REGNUM]
4293 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4294 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4296 internal_arg_pointer = virtual_incoming_args_rtx;
4297 current_function_internal_arg_pointer = internal_arg_pointer;
4299 stack_args_size.constant = 0;
4300 stack_args_size.var = 0;
4302 /* If struct value address is treated as the first argument, make it so. */
4303 if (aggregate_value_p (DECL_RESULT (fndecl))
4304 && ! current_function_returns_pcc_struct
4305 && struct_value_incoming_rtx == 0)
4307 tree type = build_pointer_type (TREE_TYPE (fntype));
4309 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4311 DECL_ARG_TYPE (function_result_decl) = type;
4312 TREE_CHAIN (function_result_decl) = fnargs;
4313 fnargs = function_result_decl;
4316 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4317 parm_reg_stack_loc = (rtx *) xcalloc (max_parm_reg, sizeof (rtx));
4319 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4320 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4322 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
4325 /* We haven't yet found an argument that we must push and pretend the
4327 current_function_pretend_args_size = 0;
4329 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4331 struct args_size stack_offset;
4332 struct args_size arg_size;
4333 int passed_pointer = 0;
4334 int did_conversion = 0;
4335 tree passed_type = DECL_ARG_TYPE (parm);
4336 tree nominal_type = TREE_TYPE (parm);
4338 int last_named = 0, named_arg;
4340 /* Set LAST_NAMED if this is last named arg before last
4342 if (stdarg || current_function_varargs)
4346 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4347 if (DECL_NAME (tem))
4353 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4354 most machines, if this is a varargs/stdarg function, then we treat
4355 the last named arg as if it were anonymous too. */
4356 named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4358 if (TREE_TYPE (parm) == error_mark_node
4359 /* This can happen after weird syntax errors
4360 or if an enum type is defined among the parms. */
4361 || TREE_CODE (parm) != PARM_DECL
4362 || passed_type == NULL)
4364 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4365 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4366 TREE_USED (parm) = 1;
4370 /* For varargs.h function, save info about regs and stack space
4371 used by the individual args, not including the va_alist arg. */
4372 if (hide_last_arg && last_named)
4373 current_function_args_info = args_so_far;
4375 /* Find mode of arg as it is passed, and mode of arg
4376 as it should be during execution of this function. */
4377 passed_mode = TYPE_MODE (passed_type);
4378 nominal_mode = TYPE_MODE (nominal_type);
4380 /* If the parm's mode is VOID, its value doesn't matter,
4381 and avoid the usual things like emit_move_insn that could crash. */
4382 if (nominal_mode == VOIDmode)
4384 SET_DECL_RTL (parm, const0_rtx);
4385 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4389 /* If the parm is to be passed as a transparent union, use the
4390 type of the first field for the tests below. We have already
4391 verified that the modes are the same. */
4392 if (DECL_TRANSPARENT_UNION (parm)
4393 || (TREE_CODE (passed_type) == UNION_TYPE
4394 && TYPE_TRANSPARENT_UNION (passed_type)))
4395 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4397 /* See if this arg was passed by invisible reference. It is if
4398 it is an object whose size depends on the contents of the
4399 object itself or if the machine requires these objects be passed
4402 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4403 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4404 || TREE_ADDRESSABLE (passed_type)
4405 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4406 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4407 passed_type, named_arg)
4411 passed_type = nominal_type = build_pointer_type (passed_type);
4413 passed_mode = nominal_mode = Pmode;
4416 promoted_mode = passed_mode;
4418 #ifdef PROMOTE_FUNCTION_ARGS
4419 /* Compute the mode in which the arg is actually extended to. */
4420 unsignedp = TREE_UNSIGNED (passed_type);
4421 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4424 /* Let machine desc say which reg (if any) the parm arrives in.
4425 0 means it arrives on the stack. */
4426 #ifdef FUNCTION_INCOMING_ARG
4427 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4428 passed_type, named_arg);
4430 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4431 passed_type, named_arg);
4434 if (entry_parm == 0)
4435 promoted_mode = passed_mode;
4437 #ifdef SETUP_INCOMING_VARARGS
4438 /* If this is the last named parameter, do any required setup for
4439 varargs or stdargs. We need to know about the case of this being an
4440 addressable type, in which case we skip the registers it
4441 would have arrived in.
4443 For stdargs, LAST_NAMED will be set for two parameters, the one that
4444 is actually the last named, and the dummy parameter. We only
4445 want to do this action once.
4447 Also, indicate when RTL generation is to be suppressed. */
4448 if (last_named && !varargs_setup)
4450 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4451 current_function_pretend_args_size, 0);
4456 /* Determine parm's home in the stack,
4457 in case it arrives in the stack or we should pretend it did.
4459 Compute the stack position and rtx where the argument arrives
4462 There is one complexity here: If this was a parameter that would
4463 have been passed in registers, but wasn't only because it is
4464 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4465 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4466 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4467 0 as it was the previous time. */
4469 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4470 locate_and_pad_parm (promoted_mode, passed_type,
4471 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4474 #ifdef FUNCTION_INCOMING_ARG
4475 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4477 pretend_named) != 0,
4479 FUNCTION_ARG (args_so_far, promoted_mode,
4481 pretend_named) != 0,
4484 fndecl, &stack_args_size, &stack_offset, &arg_size,
4488 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4490 if (offset_rtx == const0_rtx)
4491 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4493 stack_parm = gen_rtx_MEM (promoted_mode,
4494 gen_rtx_PLUS (Pmode,
4495 internal_arg_pointer,
4498 set_mem_attributes (stack_parm, parm, 1);
4501 /* If this parameter was passed both in registers and in the stack,
4502 use the copy on the stack. */
4503 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4506 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4507 /* If this parm was passed part in regs and part in memory,
4508 pretend it arrived entirely in memory
4509 by pushing the register-part onto the stack.
4511 In the special case of a DImode or DFmode that is split,
4512 we could put it together in a pseudoreg directly,
4513 but for now that's not worth bothering with. */
4517 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4518 passed_type, named_arg);
4522 current_function_pretend_args_size
4523 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4524 / (PARM_BOUNDARY / BITS_PER_UNIT)
4525 * (PARM_BOUNDARY / BITS_PER_UNIT));
4527 /* Handle calls that pass values in multiple non-contiguous
4528 locations. The Irix 6 ABI has examples of this. */
4529 if (GET_CODE (entry_parm) == PARALLEL)
4530 emit_group_store (validize_mem (stack_parm), entry_parm,
4531 int_size_in_bytes (TREE_TYPE (parm)));
4534 move_block_from_reg (REGNO (entry_parm),
4535 validize_mem (stack_parm), nregs,
4536 int_size_in_bytes (TREE_TYPE (parm)));
4538 entry_parm = stack_parm;
4543 /* If we didn't decide this parm came in a register,
4544 by default it came on the stack. */
4545 if (entry_parm == 0)
4546 entry_parm = stack_parm;
4548 /* Record permanently how this parm was passed. */
4549 DECL_INCOMING_RTL (parm) = entry_parm;
4551 /* If there is actually space on the stack for this parm,
4552 count it in stack_args_size; otherwise set stack_parm to 0
4553 to indicate there is no preallocated stack slot for the parm. */
4555 if (entry_parm == stack_parm
4556 || (GET_CODE (entry_parm) == PARALLEL
4557 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4558 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4559 /* On some machines, even if a parm value arrives in a register
4560 there is still an (uninitialized) stack slot allocated for it.
4562 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4563 whether this parameter already has a stack slot allocated,
4564 because an arg block exists only if current_function_args_size
4565 is larger than some threshold, and we haven't calculated that
4566 yet. So, for now, we just assume that stack slots never exist
4568 || REG_PARM_STACK_SPACE (fndecl) > 0
4572 stack_args_size.constant += arg_size.constant;
4574 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4577 /* No stack slot was pushed for this parm. */
4580 /* Update info on where next arg arrives in registers. */
4582 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4583 passed_type, named_arg);
4585 /* If we can't trust the parm stack slot to be aligned enough
4586 for its ultimate type, don't use that slot after entry.
4587 We'll make another stack slot, if we need one. */
4589 unsigned int thisparm_boundary
4590 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4592 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4596 /* If parm was passed in memory, and we need to convert it on entry,
4597 don't store it back in that same slot. */
4599 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4602 /* When an argument is passed in multiple locations, we can't
4603 make use of this information, but we can save some copying if
4604 the whole argument is passed in a single register. */
4605 if (GET_CODE (entry_parm) == PARALLEL
4606 && nominal_mode != BLKmode && passed_mode != BLKmode)
4608 int i, len = XVECLEN (entry_parm, 0);
4610 for (i = 0; i < len; i++)
4611 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4612 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4613 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4615 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4617 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4618 DECL_INCOMING_RTL (parm) = entry_parm;
4623 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4624 in the mode in which it arrives.
4625 STACK_PARM is an RTX for a stack slot where the parameter can live
4626 during the function (in case we want to put it there).
4627 STACK_PARM is 0 if no stack slot was pushed for it.
4629 Now output code if necessary to convert ENTRY_PARM to
4630 the type in which this function declares it,
4631 and store that result in an appropriate place,
4632 which may be a pseudo reg, may be STACK_PARM,
4633 or may be a local stack slot if STACK_PARM is 0.
4635 Set DECL_RTL to that place. */
4637 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4639 /* If a BLKmode arrives in registers, copy it to a stack slot.
4640 Handle calls that pass values in multiple non-contiguous
4641 locations. The Irix 6 ABI has examples of this. */
4642 if (GET_CODE (entry_parm) == REG
4643 || GET_CODE (entry_parm) == PARALLEL)
4646 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4649 /* Note that we will be storing an integral number of words.
4650 So we have to be careful to ensure that we allocate an
4651 integral number of words. We do this below in the
4652 assign_stack_local if space was not allocated in the argument
4653 list. If it was, this will not work if PARM_BOUNDARY is not
4654 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4655 if it becomes a problem. */
4657 if (stack_parm == 0)
4660 = assign_stack_local (GET_MODE (entry_parm),
4662 set_mem_attributes (stack_parm, parm, 1);
4665 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4668 /* Handle calls that pass values in multiple non-contiguous
4669 locations. The Irix 6 ABI has examples of this. */
4670 if (GET_CODE (entry_parm) == PARALLEL)
4671 emit_group_store (validize_mem (stack_parm), entry_parm,
4672 int_size_in_bytes (TREE_TYPE (parm)));
4674 move_block_from_reg (REGNO (entry_parm),
4675 validize_mem (stack_parm),
4676 size_stored / UNITS_PER_WORD,
4677 int_size_in_bytes (TREE_TYPE (parm)));
4679 SET_DECL_RTL (parm, stack_parm);
4681 else if (! ((! optimize
4682 && ! DECL_REGISTER (parm))
4683 || TREE_SIDE_EFFECTS (parm)
4684 /* If -ffloat-store specified, don't put explicit
4685 float variables into registers. */
4686 || (flag_float_store
4687 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4688 /* Always assign pseudo to structure return or item passed
4689 by invisible reference. */
4690 || passed_pointer || parm == function_result_decl)
4692 /* Store the parm in a pseudoregister during the function, but we
4693 may need to do it in a wider mode. */
4696 unsigned int regno, regnoi = 0, regnor = 0;
4698 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4700 promoted_nominal_mode
4701 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4703 parmreg = gen_reg_rtx (promoted_nominal_mode);
4704 mark_user_reg (parmreg);
4706 /* If this was an item that we received a pointer to, set DECL_RTL
4710 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4712 set_mem_attributes (x, parm, 1);
4713 SET_DECL_RTL (parm, x);
4717 SET_DECL_RTL (parm, parmreg);
4718 maybe_set_unchanging (DECL_RTL (parm), parm);
4721 /* Copy the value into the register. */
4722 if (nominal_mode != passed_mode
4723 || promoted_nominal_mode != promoted_mode)
4726 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4727 mode, by the caller. We now have to convert it to
4728 NOMINAL_MODE, if different. However, PARMREG may be in
4729 a different mode than NOMINAL_MODE if it is being stored
4732 If ENTRY_PARM is a hard register, it might be in a register
4733 not valid for operating in its mode (e.g., an odd-numbered
4734 register for a DFmode). In that case, moves are the only
4735 thing valid, so we can't do a convert from there. This
4736 occurs when the calling sequence allow such misaligned
4739 In addition, the conversion may involve a call, which could
4740 clobber parameters which haven't been copied to pseudo
4741 registers yet. Therefore, we must first copy the parm to
4742 a pseudo reg here, and save the conversion until after all
4743 parameters have been moved. */
4745 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4747 emit_move_insn (tempreg, validize_mem (entry_parm));
4749 push_to_sequence (conversion_insns);
4750 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4752 if (GET_CODE (tempreg) == SUBREG
4753 && GET_MODE (tempreg) == nominal_mode
4754 && GET_CODE (SUBREG_REG (tempreg)) == REG
4755 && nominal_mode == passed_mode
4756 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4757 && GET_MODE_SIZE (GET_MODE (tempreg))
4758 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4760 /* The argument is already sign/zero extended, so note it
4762 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4763 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4766 /* TREE_USED gets set erroneously during expand_assignment. */
4767 save_tree_used = TREE_USED (parm);
4768 expand_assignment (parm,
4769 make_tree (nominal_type, tempreg), 0, 0);
4770 TREE_USED (parm) = save_tree_used;
4771 conversion_insns = get_insns ();
4776 emit_move_insn (parmreg, validize_mem (entry_parm));
4778 /* If we were passed a pointer but the actual value
4779 can safely live in a register, put it in one. */
4780 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4781 /* If by-reference argument was promoted, demote it. */
4782 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4784 && ! DECL_REGISTER (parm))
4785 || TREE_SIDE_EFFECTS (parm)
4786 /* If -ffloat-store specified, don't put explicit
4787 float variables into registers. */
4788 || (flag_float_store
4789 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4791 /* We can't use nominal_mode, because it will have been set to
4792 Pmode above. We must use the actual mode of the parm. */
4793 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4794 mark_user_reg (parmreg);
4795 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4797 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4798 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4799 push_to_sequence (conversion_insns);
4800 emit_move_insn (tempreg, DECL_RTL (parm));
4802 convert_to_mode (GET_MODE (parmreg),
4805 emit_move_insn (parmreg, DECL_RTL (parm));
4806 conversion_insns = get_insns();
4811 emit_move_insn (parmreg, DECL_RTL (parm));
4812 SET_DECL_RTL (parm, parmreg);
4813 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4817 #ifdef FUNCTION_ARG_CALLEE_COPIES
4818 /* If we are passed an arg by reference and it is our responsibility
4819 to make a copy, do it now.
4820 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4821 original argument, so we must recreate them in the call to
4822 FUNCTION_ARG_CALLEE_COPIES. */
4823 /* ??? Later add code to handle the case that if the argument isn't
4824 modified, don't do the copy. */
4826 else if (passed_pointer
4827 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4828 TYPE_MODE (DECL_ARG_TYPE (parm)),
4829 DECL_ARG_TYPE (parm),
4831 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4834 tree type = DECL_ARG_TYPE (parm);
4836 /* This sequence may involve a library call perhaps clobbering
4837 registers that haven't been copied to pseudos yet. */
4839 push_to_sequence (conversion_insns);
4841 if (!COMPLETE_TYPE_P (type)
4842 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4843 /* This is a variable sized object. */
4844 copy = gen_rtx_MEM (BLKmode,
4845 allocate_dynamic_stack_space
4846 (expr_size (parm), NULL_RTX,
4847 TYPE_ALIGN (type)));
4849 copy = assign_stack_temp (TYPE_MODE (type),
4850 int_size_in_bytes (type), 1);
4851 set_mem_attributes (copy, parm, 1);
4853 store_expr (parm, copy, 0);
4854 emit_move_insn (parmreg, XEXP (copy, 0));
4855 conversion_insns = get_insns ();
4859 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4861 /* In any case, record the parm's desired stack location
4862 in case we later discover it must live in the stack.
4864 If it is a COMPLEX value, store the stack location for both
4867 if (GET_CODE (parmreg) == CONCAT)
4868 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4870 regno = REGNO (parmreg);
4872 if (regno >= max_parm_reg)
4875 int old_max_parm_reg = max_parm_reg;
4877 /* It's slow to expand this one register at a time,
4878 but it's also rare and we need max_parm_reg to be
4879 precisely correct. */
4880 max_parm_reg = regno + 1;
4881 new = (rtx *) xrealloc (parm_reg_stack_loc,
4882 max_parm_reg * sizeof (rtx));
4883 memset ((char *) (new + old_max_parm_reg), 0,
4884 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4885 parm_reg_stack_loc = new;
4888 if (GET_CODE (parmreg) == CONCAT)
4890 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4892 regnor = REGNO (gen_realpart (submode, parmreg));
4893 regnoi = REGNO (gen_imagpart (submode, parmreg));
4895 if (stack_parm != 0)
4897 parm_reg_stack_loc[regnor]
4898 = gen_realpart (submode, stack_parm);
4899 parm_reg_stack_loc[regnoi]
4900 = gen_imagpart (submode, stack_parm);
4904 parm_reg_stack_loc[regnor] = 0;
4905 parm_reg_stack_loc[regnoi] = 0;
4909 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4911 /* Mark the register as eliminable if we did no conversion
4912 and it was copied from memory at a fixed offset,
4913 and the arg pointer was not copied to a pseudo-reg.
4914 If the arg pointer is a pseudo reg or the offset formed
4915 an invalid address, such memory-equivalences
4916 as we make here would screw up life analysis for it. */
4917 if (nominal_mode == passed_mode
4920 && GET_CODE (stack_parm) == MEM
4921 && stack_offset.var == 0
4922 && reg_mentioned_p (virtual_incoming_args_rtx,
4923 XEXP (stack_parm, 0)))
4925 rtx linsn = get_last_insn ();
4928 /* Mark complex types separately. */
4929 if (GET_CODE (parmreg) == CONCAT)
4930 /* Scan backwards for the set of the real and
4932 for (sinsn = linsn; sinsn != 0;
4933 sinsn = prev_nonnote_insn (sinsn))
4935 set = single_set (sinsn);
4937 && SET_DEST (set) == regno_reg_rtx [regnoi])
4939 = gen_rtx_EXPR_LIST (REG_EQUIV,
4940 parm_reg_stack_loc[regnoi],
4943 && SET_DEST (set) == regno_reg_rtx [regnor])
4945 = gen_rtx_EXPR_LIST (REG_EQUIV,
4946 parm_reg_stack_loc[regnor],
4949 else if ((set = single_set (linsn)) != 0
4950 && SET_DEST (set) == parmreg)
4952 = gen_rtx_EXPR_LIST (REG_EQUIV,
4953 stack_parm, REG_NOTES (linsn));
4956 /* For pointer data type, suggest pointer register. */
4957 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4958 mark_reg_pointer (parmreg,
4959 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4961 /* If something wants our address, try to use ADDRESSOF. */
4962 if (TREE_ADDRESSABLE (parm))
4964 /* If we end up putting something into the stack,
4965 fixup_var_refs_insns will need to make a pass over
4966 all the instructions. It looks through the pending
4967 sequences -- but it can't see the ones in the
4968 CONVERSION_INSNS, if they're not on the sequence
4969 stack. So, we go back to that sequence, just so that
4970 the fixups will happen. */
4971 push_to_sequence (conversion_insns);
4972 put_var_into_stack (parm);
4973 conversion_insns = get_insns ();
4979 /* Value must be stored in the stack slot STACK_PARM
4980 during function execution. */
4982 if (promoted_mode != nominal_mode)
4984 /* Conversion is required. */
4985 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4987 emit_move_insn (tempreg, validize_mem (entry_parm));
4989 push_to_sequence (conversion_insns);
4990 entry_parm = convert_to_mode (nominal_mode, tempreg,
4991 TREE_UNSIGNED (TREE_TYPE (parm)));
4993 /* ??? This may need a big-endian conversion on sparc64. */
4994 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
4996 conversion_insns = get_insns ();
5001 if (entry_parm != stack_parm)
5003 if (stack_parm == 0)
5006 = assign_stack_local (GET_MODE (entry_parm),
5007 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
5008 set_mem_attributes (stack_parm, parm, 1);
5011 if (promoted_mode != nominal_mode)
5013 push_to_sequence (conversion_insns);
5014 emit_move_insn (validize_mem (stack_parm),
5015 validize_mem (entry_parm));
5016 conversion_insns = get_insns ();
5020 emit_move_insn (validize_mem (stack_parm),
5021 validize_mem (entry_parm));
5024 SET_DECL_RTL (parm, stack_parm);
5027 /* If this "parameter" was the place where we are receiving the
5028 function's incoming structure pointer, set up the result. */
5029 if (parm == function_result_decl)
5031 tree result = DECL_RESULT (fndecl);
5032 rtx addr = DECL_RTL (parm);
5035 #ifdef POINTERS_EXTEND_UNSIGNED
5036 if (GET_MODE (addr) != Pmode)
5037 addr = convert_memory_address (Pmode, addr);
5040 x = gen_rtx_MEM (DECL_MODE (result), addr);
5041 set_mem_attributes (x, result, 1);
5042 SET_DECL_RTL (result, x);
5045 if (GET_CODE (DECL_RTL (parm)) == REG)
5046 REGNO_DECL (REGNO (DECL_RTL (parm))) = parm;
5047 else if (GET_CODE (DECL_RTL (parm)) == CONCAT)
5049 REGNO_DECL (REGNO (XEXP (DECL_RTL (parm), 0))) = parm;
5050 REGNO_DECL (REGNO (XEXP (DECL_RTL (parm), 1))) = parm;
5055 /* Output all parameter conversion instructions (possibly including calls)
5056 now that all parameters have been copied out of hard registers. */
5057 emit_insns (conversion_insns);
5059 last_parm_insn = get_last_insn ();
5061 current_function_args_size = stack_args_size.constant;
5063 /* Adjust function incoming argument size for alignment and
5066 #ifdef REG_PARM_STACK_SPACE
5067 #ifndef MAYBE_REG_PARM_STACK_SPACE
5068 current_function_args_size = MAX (current_function_args_size,
5069 REG_PARM_STACK_SPACE (fndecl));
5073 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
5075 current_function_args_size
5076 = ((current_function_args_size + STACK_BYTES - 1)
5077 / STACK_BYTES) * STACK_BYTES;
5079 #ifdef ARGS_GROW_DOWNWARD
5080 current_function_arg_offset_rtx
5081 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5082 : expand_expr (size_diffop (stack_args_size.var,
5083 size_int (-stack_args_size.constant)),
5084 NULL_RTX, VOIDmode, 0));
5086 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5089 /* See how many bytes, if any, of its args a function should try to pop
5092 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5093 current_function_args_size);
5095 /* For stdarg.h function, save info about
5096 regs and stack space used by the named args. */
5099 current_function_args_info = args_so_far;
5101 /* Set the rtx used for the function return value. Put this in its
5102 own variable so any optimizers that need this information don't have
5103 to include tree.h. Do this here so it gets done when an inlined
5104 function gets output. */
5106 current_function_return_rtx
5107 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5108 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5111 /* Indicate whether REGNO is an incoming argument to the current function
5112 that was promoted to a wider mode. If so, return the RTX for the
5113 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5114 that REGNO is promoted from and whether the promotion was signed or
5117 #ifdef PROMOTE_FUNCTION_ARGS
5120 promoted_input_arg (regno, pmode, punsignedp)
5122 enum machine_mode *pmode;
5127 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5128 arg = TREE_CHAIN (arg))
5129 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5130 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5131 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5133 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5134 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5136 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5137 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5138 && mode != DECL_MODE (arg))
5140 *pmode = DECL_MODE (arg);
5141 *punsignedp = unsignedp;
5142 return DECL_INCOMING_RTL (arg);
5151 /* Compute the size and offset from the start of the stacked arguments for a
5152 parm passed in mode PASSED_MODE and with type TYPE.
5154 INITIAL_OFFSET_PTR points to the current offset into the stacked
5157 The starting offset and size for this parm are returned in *OFFSET_PTR
5158 and *ARG_SIZE_PTR, respectively.
5160 IN_REGS is non-zero if the argument will be passed in registers. It will
5161 never be set if REG_PARM_STACK_SPACE is not defined.
5163 FNDECL is the function in which the argument was defined.
5165 There are two types of rounding that are done. The first, controlled by
5166 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5167 list to be aligned to the specific boundary (in bits). This rounding
5168 affects the initial and starting offsets, but not the argument size.
5170 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5171 optionally rounds the size of the parm to PARM_BOUNDARY. The
5172 initial offset is not affected by this rounding, while the size always
5173 is and the starting offset may be. */
5175 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
5176 initial_offset_ptr is positive because locate_and_pad_parm's
5177 callers pass in the total size of args so far as
5178 initial_offset_ptr. arg_size_ptr is always positive. */
5181 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
5182 initial_offset_ptr, offset_ptr, arg_size_ptr,
5184 enum machine_mode passed_mode;
5186 int in_regs ATTRIBUTE_UNUSED;
5187 tree fndecl ATTRIBUTE_UNUSED;
5188 struct args_size *initial_offset_ptr;
5189 struct args_size *offset_ptr;
5190 struct args_size *arg_size_ptr;
5191 struct args_size *alignment_pad;
5195 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5196 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5197 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5199 #ifdef REG_PARM_STACK_SPACE
5200 /* If we have found a stack parm before we reach the end of the
5201 area reserved for registers, skip that area. */
5204 int reg_parm_stack_space = 0;
5206 #ifdef MAYBE_REG_PARM_STACK_SPACE
5207 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5209 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5211 if (reg_parm_stack_space > 0)
5213 if (initial_offset_ptr->var)
5215 initial_offset_ptr->var
5216 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5217 ssize_int (reg_parm_stack_space));
5218 initial_offset_ptr->constant = 0;
5220 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5221 initial_offset_ptr->constant = reg_parm_stack_space;
5224 #endif /* REG_PARM_STACK_SPACE */
5226 arg_size_ptr->var = 0;
5227 arg_size_ptr->constant = 0;
5228 alignment_pad->var = 0;
5229 alignment_pad->constant = 0;
5231 #ifdef ARGS_GROW_DOWNWARD
5232 if (initial_offset_ptr->var)
5234 offset_ptr->constant = 0;
5235 offset_ptr->var = size_binop (MINUS_EXPR, ssize_int (0),
5236 initial_offset_ptr->var);
5240 offset_ptr->constant = -initial_offset_ptr->constant;
5241 offset_ptr->var = 0;
5243 if (where_pad != none
5244 && (!host_integerp (sizetree, 1)
5245 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5246 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5247 SUB_PARM_SIZE (*offset_ptr, sizetree);
5248 if (where_pad != downward)
5249 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5250 if (initial_offset_ptr->var)
5251 arg_size_ptr->var = size_binop (MINUS_EXPR,
5252 size_binop (MINUS_EXPR,
5254 initial_offset_ptr->var),
5258 arg_size_ptr->constant = (-initial_offset_ptr->constant
5259 - offset_ptr->constant);
5261 #else /* !ARGS_GROW_DOWNWARD */
5263 #ifdef REG_PARM_STACK_SPACE
5264 || REG_PARM_STACK_SPACE (fndecl) > 0
5267 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5268 *offset_ptr = *initial_offset_ptr;
5270 #ifdef PUSH_ROUNDING
5271 if (passed_mode != BLKmode)
5272 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5275 /* Pad_below needs the pre-rounded size to know how much to pad below
5276 so this must be done before rounding up. */
5277 if (where_pad == downward
5278 /* However, BLKmode args passed in regs have their padding done elsewhere.
5279 The stack slot must be able to hold the entire register. */
5280 && !(in_regs && passed_mode == BLKmode))
5281 pad_below (offset_ptr, passed_mode, sizetree);
5283 if (where_pad != none
5284 && (!host_integerp (sizetree, 1)
5285 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5286 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5288 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5289 #endif /* ARGS_GROW_DOWNWARD */
5292 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5293 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5296 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5297 struct args_size *offset_ptr;
5299 struct args_size *alignment_pad;
5301 tree save_var = NULL_TREE;
5302 HOST_WIDE_INT save_constant = 0;
5304 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5306 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5308 save_var = offset_ptr->var;
5309 save_constant = offset_ptr->constant;
5312 alignment_pad->var = NULL_TREE;
5313 alignment_pad->constant = 0;
5315 if (boundary > BITS_PER_UNIT)
5317 if (offset_ptr->var)
5320 #ifdef ARGS_GROW_DOWNWARD
5325 (ARGS_SIZE_TREE (*offset_ptr),
5326 boundary / BITS_PER_UNIT);
5327 offset_ptr->constant = 0; /*?*/
5328 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5329 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5334 offset_ptr->constant =
5335 #ifdef ARGS_GROW_DOWNWARD
5336 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5338 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5340 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5341 alignment_pad->constant = offset_ptr->constant - save_constant;
5346 #ifndef ARGS_GROW_DOWNWARD
5348 pad_below (offset_ptr, passed_mode, sizetree)
5349 struct args_size *offset_ptr;
5350 enum machine_mode passed_mode;
5353 if (passed_mode != BLKmode)
5355 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5356 offset_ptr->constant
5357 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5358 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5359 - GET_MODE_SIZE (passed_mode));
5363 if (TREE_CODE (sizetree) != INTEGER_CST
5364 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5366 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5367 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5369 ADD_PARM_SIZE (*offset_ptr, s2);
5370 SUB_PARM_SIZE (*offset_ptr, sizetree);
5376 /* Walk the tree of blocks describing the binding levels within a function
5377 and warn about uninitialized variables.
5378 This is done after calling flow_analysis and before global_alloc
5379 clobbers the pseudo-regs to hard regs. */
5382 uninitialized_vars_warning (block)
5386 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5388 if (warn_uninitialized
5389 && TREE_CODE (decl) == VAR_DECL
5390 /* These warnings are unreliable for and aggregates
5391 because assigning the fields one by one can fail to convince
5392 flow.c that the entire aggregate was initialized.
5393 Unions are troublesome because members may be shorter. */
5394 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5395 && DECL_RTL (decl) != 0
5396 && GET_CODE (DECL_RTL (decl)) == REG
5397 /* Global optimizations can make it difficult to determine if a
5398 particular variable has been initialized. However, a VAR_DECL
5399 with a nonzero DECL_INITIAL had an initializer, so do not
5400 claim it is potentially uninitialized.
5402 We do not care about the actual value in DECL_INITIAL, so we do
5403 not worry that it may be a dangling pointer. */
5404 && DECL_INITIAL (decl) == NULL_TREE
5405 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5406 warning_with_decl (decl,
5407 "`%s' might be used uninitialized in this function");
5409 && TREE_CODE (decl) == VAR_DECL
5410 && DECL_RTL (decl) != 0
5411 && GET_CODE (DECL_RTL (decl)) == REG
5412 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5413 warning_with_decl (decl,
5414 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5416 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5417 uninitialized_vars_warning (sub);
5420 /* Do the appropriate part of uninitialized_vars_warning
5421 but for arguments instead of local variables. */
5424 setjmp_args_warning ()
5427 for (decl = DECL_ARGUMENTS (current_function_decl);
5428 decl; decl = TREE_CHAIN (decl))
5429 if (DECL_RTL (decl) != 0
5430 && GET_CODE (DECL_RTL (decl)) == REG
5431 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5432 warning_with_decl (decl,
5433 "argument `%s' might be clobbered by `longjmp' or `vfork'");
5436 /* If this function call setjmp, put all vars into the stack
5437 unless they were declared `register'. */
5440 setjmp_protect (block)
5444 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5445 if ((TREE_CODE (decl) == VAR_DECL
5446 || TREE_CODE (decl) == PARM_DECL)
5447 && DECL_RTL (decl) != 0
5448 && (GET_CODE (DECL_RTL (decl)) == REG
5449 || (GET_CODE (DECL_RTL (decl)) == MEM
5450 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5451 /* If this variable came from an inline function, it must be
5452 that its life doesn't overlap the setjmp. If there was a
5453 setjmp in the function, it would already be in memory. We
5454 must exclude such variable because their DECL_RTL might be
5455 set to strange things such as virtual_stack_vars_rtx. */
5456 && ! DECL_FROM_INLINE (decl)
5458 #ifdef NON_SAVING_SETJMP
5459 /* If longjmp doesn't restore the registers,
5460 don't put anything in them. */
5464 ! DECL_REGISTER (decl)))
5465 put_var_into_stack (decl);
5466 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5467 setjmp_protect (sub);
5470 /* Like the previous function, but for args instead of local variables. */
5473 setjmp_protect_args ()
5476 for (decl = DECL_ARGUMENTS (current_function_decl);
5477 decl; decl = TREE_CHAIN (decl))
5478 if ((TREE_CODE (decl) == VAR_DECL
5479 || TREE_CODE (decl) == PARM_DECL)
5480 && DECL_RTL (decl) != 0
5481 && (GET_CODE (DECL_RTL (decl)) == REG
5482 || (GET_CODE (DECL_RTL (decl)) == MEM
5483 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5485 /* If longjmp doesn't restore the registers,
5486 don't put anything in them. */
5487 #ifdef NON_SAVING_SETJMP
5491 ! DECL_REGISTER (decl)))
5492 put_var_into_stack (decl);
5495 /* Return the context-pointer register corresponding to DECL,
5496 or 0 if it does not need one. */
5499 lookup_static_chain (decl)
5502 tree context = decl_function_context (decl);
5506 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5509 /* We treat inline_function_decl as an alias for the current function
5510 because that is the inline function whose vars, types, etc.
5511 are being merged into the current function.
5512 See expand_inline_function. */
5513 if (context == current_function_decl || context == inline_function_decl)
5514 return virtual_stack_vars_rtx;
5516 for (link = context_display; link; link = TREE_CHAIN (link))
5517 if (TREE_PURPOSE (link) == context)
5518 return RTL_EXPR_RTL (TREE_VALUE (link));
5523 /* Convert a stack slot address ADDR for variable VAR
5524 (from a containing function)
5525 into an address valid in this function (using a static chain). */
5528 fix_lexical_addr (addr, var)
5533 HOST_WIDE_INT displacement;
5534 tree context = decl_function_context (var);
5535 struct function *fp;
5538 /* If this is the present function, we need not do anything. */
5539 if (context == current_function_decl || context == inline_function_decl)
5542 fp = find_function_data (context);
5544 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5545 addr = XEXP (XEXP (addr, 0), 0);
5547 /* Decode given address as base reg plus displacement. */
5548 if (GET_CODE (addr) == REG)
5549 basereg = addr, displacement = 0;
5550 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5551 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5555 /* We accept vars reached via the containing function's
5556 incoming arg pointer and via its stack variables pointer. */
5557 if (basereg == fp->internal_arg_pointer)
5559 /* If reached via arg pointer, get the arg pointer value
5560 out of that function's stack frame.
5562 There are two cases: If a separate ap is needed, allocate a
5563 slot in the outer function for it and dereference it that way.
5564 This is correct even if the real ap is actually a pseudo.
5565 Otherwise, just adjust the offset from the frame pointer to
5568 #ifdef NEED_SEPARATE_AP
5571 addr = get_arg_pointer_save_area (fp);
5572 addr = fix_lexical_addr (XEXP (addr, 0), var);
5573 addr = memory_address (Pmode, addr);
5575 base = gen_rtx_MEM (Pmode, addr);
5576 set_mem_alias_set (base, get_frame_alias_set ());
5577 base = copy_to_reg (base);
5579 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5580 base = lookup_static_chain (var);
5584 else if (basereg == virtual_stack_vars_rtx)
5586 /* This is the same code as lookup_static_chain, duplicated here to
5587 avoid an extra call to decl_function_context. */
5590 for (link = context_display; link; link = TREE_CHAIN (link))
5591 if (TREE_PURPOSE (link) == context)
5593 base = RTL_EXPR_RTL (TREE_VALUE (link));
5601 /* Use same offset, relative to appropriate static chain or argument
5603 return plus_constant (base, displacement);
5606 /* Return the address of the trampoline for entering nested fn FUNCTION.
5607 If necessary, allocate a trampoline (in the stack frame)
5608 and emit rtl to initialize its contents (at entry to this function). */
5611 trampoline_address (function)
5617 struct function *fp;
5620 /* Find an existing trampoline and return it. */
5621 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5622 if (TREE_PURPOSE (link) == function)
5624 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5626 for (fp = outer_function_chain; fp; fp = fp->outer)
5627 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5628 if (TREE_PURPOSE (link) == function)
5630 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5632 return adjust_trampoline_addr (tramp);
5635 /* None exists; we must make one. */
5637 /* Find the `struct function' for the function containing FUNCTION. */
5639 fn_context = decl_function_context (function);
5640 if (fn_context != current_function_decl
5641 && fn_context != inline_function_decl)
5642 fp = find_function_data (fn_context);
5644 /* Allocate run-time space for this trampoline
5645 (usually in the defining function's stack frame). */
5646 #ifdef ALLOCATE_TRAMPOLINE
5647 tramp = ALLOCATE_TRAMPOLINE (fp);
5649 /* If rounding needed, allocate extra space
5650 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5651 #ifdef TRAMPOLINE_ALIGNMENT
5652 #define TRAMPOLINE_REAL_SIZE \
5653 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5655 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5657 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5661 /* Record the trampoline for reuse and note it for later initialization
5662 by expand_function_end. */
5665 rtlexp = make_node (RTL_EXPR);
5666 RTL_EXPR_RTL (rtlexp) = tramp;
5667 fp->x_trampoline_list = tree_cons (function, rtlexp,
5668 fp->x_trampoline_list);
5672 /* Make the RTL_EXPR node temporary, not momentary, so that the
5673 trampoline_list doesn't become garbage. */
5674 rtlexp = make_node (RTL_EXPR);
5676 RTL_EXPR_RTL (rtlexp) = tramp;
5677 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5680 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5681 return adjust_trampoline_addr (tramp);
5684 /* Given a trampoline address,
5685 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5688 round_trampoline_addr (tramp)
5691 #ifdef TRAMPOLINE_ALIGNMENT
5692 /* Round address up to desired boundary. */
5693 rtx temp = gen_reg_rtx (Pmode);
5694 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
5695 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5697 temp = expand_simple_binop (Pmode, PLUS, tramp, addend,
5698 temp, 0, OPTAB_LIB_WIDEN);
5699 tramp = expand_simple_binop (Pmode, AND, temp, mask,
5700 temp, 0, OPTAB_LIB_WIDEN);
5705 /* Given a trampoline address, round it then apply any
5706 platform-specific adjustments so that the result can be used for a
5710 adjust_trampoline_addr (tramp)
5713 tramp = round_trampoline_addr (tramp);
5714 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5715 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5720 /* Put all this function's BLOCK nodes including those that are chained
5721 onto the first block into a vector, and return it.
5722 Also store in each NOTE for the beginning or end of a block
5723 the index of that block in the vector.
5724 The arguments are BLOCK, the chain of top-level blocks of the function,
5725 and INSNS, the insn chain of the function. */
5731 tree *block_vector, *last_block_vector;
5733 tree block = DECL_INITIAL (current_function_decl);
5738 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5739 depth-first order. */
5740 block_vector = get_block_vector (block, &n_blocks);
5741 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5743 last_block_vector = identify_blocks_1 (get_insns (),
5745 block_vector + n_blocks,
5748 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5749 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5750 if (0 && last_block_vector != block_vector + n_blocks)
5753 free (block_vector);
5757 /* Subroutine of identify_blocks. Do the block substitution on the
5758 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5760 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5761 BLOCK_VECTOR is incremented for each block seen. */
5764 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5767 tree *end_block_vector;
5768 tree *orig_block_stack;
5771 tree *block_stack = orig_block_stack;
5773 for (insn = insns; insn; insn = NEXT_INSN (insn))
5775 if (GET_CODE (insn) == NOTE)
5777 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5781 /* If there are more block notes than BLOCKs, something
5783 if (block_vector == end_block_vector)
5786 b = *block_vector++;
5787 NOTE_BLOCK (insn) = b;
5790 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5792 /* If there are more NOTE_INSN_BLOCK_ENDs than
5793 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5794 if (block_stack == orig_block_stack)
5797 NOTE_BLOCK (insn) = *--block_stack;
5800 else if (GET_CODE (insn) == CALL_INSN
5801 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5803 rtx cp = PATTERN (insn);
5805 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5806 end_block_vector, block_stack);
5808 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5809 end_block_vector, block_stack);
5811 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5812 end_block_vector, block_stack);
5816 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5817 something is badly wrong. */
5818 if (block_stack != orig_block_stack)
5821 return block_vector;
5824 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5825 and create duplicate blocks. */
5826 /* ??? Need an option to either create block fragments or to create
5827 abstract origin duplicates of a source block. It really depends
5828 on what optimization has been performed. */
5833 tree block = DECL_INITIAL (current_function_decl);
5834 varray_type block_stack;
5836 if (block == NULL_TREE)
5839 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5841 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
5842 reorder_blocks_0 (block);
5844 /* Prune the old trees away, so that they don't get in the way. */
5845 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5846 BLOCK_CHAIN (block) = NULL_TREE;
5848 /* Recreate the block tree from the note nesting. */
5849 reorder_blocks_1 (get_insns (), block, &block_stack);
5850 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5852 /* Remove deleted blocks from the block fragment chains. */
5853 reorder_fix_fragments (block);
5855 VARRAY_FREE (block_stack);
5858 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
5861 reorder_blocks_0 (block)
5866 TREE_ASM_WRITTEN (block) = 0;
5867 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
5868 block = BLOCK_CHAIN (block);
5873 reorder_blocks_1 (insns, current_block, p_block_stack)
5876 varray_type *p_block_stack;
5880 for (insn = insns; insn; insn = NEXT_INSN (insn))
5882 if (GET_CODE (insn) == NOTE)
5884 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5886 tree block = NOTE_BLOCK (insn);
5888 /* If we have seen this block before, that means it now
5889 spans multiple address regions. Create a new fragment. */
5890 if (TREE_ASM_WRITTEN (block))
5892 tree new_block = copy_node (block);
5895 origin = (BLOCK_FRAGMENT_ORIGIN (block)
5896 ? BLOCK_FRAGMENT_ORIGIN (block)
5898 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
5899 BLOCK_FRAGMENT_CHAIN (new_block)
5900 = BLOCK_FRAGMENT_CHAIN (origin);
5901 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
5903 NOTE_BLOCK (insn) = new_block;
5907 BLOCK_SUBBLOCKS (block) = 0;
5908 TREE_ASM_WRITTEN (block) = 1;
5909 BLOCK_SUPERCONTEXT (block) = current_block;
5910 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5911 BLOCK_SUBBLOCKS (current_block) = block;
5912 current_block = block;
5913 VARRAY_PUSH_TREE (*p_block_stack, block);
5915 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5917 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
5918 VARRAY_POP (*p_block_stack);
5919 BLOCK_SUBBLOCKS (current_block)
5920 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5921 current_block = BLOCK_SUPERCONTEXT (current_block);
5924 else if (GET_CODE (insn) == CALL_INSN
5925 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5927 rtx cp = PATTERN (insn);
5928 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
5930 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
5932 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
5937 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
5938 appears in the block tree, select one of the fragments to become
5939 the new origin block. */
5942 reorder_fix_fragments (block)
5947 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
5948 tree new_origin = NULL_TREE;
5952 if (! TREE_ASM_WRITTEN (dup_origin))
5954 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
5956 /* Find the first of the remaining fragments. There must
5957 be at least one -- the current block. */
5958 while (! TREE_ASM_WRITTEN (new_origin))
5959 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
5960 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
5963 else if (! dup_origin)
5966 /* Re-root the rest of the fragments to the new origin. In the
5967 case that DUP_ORIGIN was null, that means BLOCK was the origin
5968 of a chain of fragments and we want to remove those fragments
5969 that didn't make it to the output. */
5972 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
5977 if (TREE_ASM_WRITTEN (chain))
5979 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
5981 pp = &BLOCK_FRAGMENT_CHAIN (chain);
5983 chain = BLOCK_FRAGMENT_CHAIN (chain);
5988 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
5989 block = BLOCK_CHAIN (block);
5993 /* Reverse the order of elements in the chain T of blocks,
5994 and return the new head of the chain (old last element). */
6000 tree prev = 0, decl, next;
6001 for (decl = t; decl; decl = next)
6003 next = BLOCK_CHAIN (decl);
6004 BLOCK_CHAIN (decl) = prev;
6010 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6011 non-NULL, list them all into VECTOR, in a depth-first preorder
6012 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6016 all_blocks (block, vector)
6024 TREE_ASM_WRITTEN (block) = 0;
6026 /* Record this block. */
6028 vector[n_blocks] = block;
6032 /* Record the subblocks, and their subblocks... */
6033 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6034 vector ? vector + n_blocks : 0);
6035 block = BLOCK_CHAIN (block);
6041 /* Return a vector containing all the blocks rooted at BLOCK. The
6042 number of elements in the vector is stored in N_BLOCKS_P. The
6043 vector is dynamically allocated; it is the caller's responsibility
6044 to call `free' on the pointer returned. */
6047 get_block_vector (block, n_blocks_p)
6053 *n_blocks_p = all_blocks (block, NULL);
6054 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
6055 all_blocks (block, block_vector);
6057 return block_vector;
6060 static int next_block_index = 2;
6062 /* Set BLOCK_NUMBER for all the blocks in FN. */
6072 /* For SDB and XCOFF debugging output, we start numbering the blocks
6073 from 1 within each function, rather than keeping a running
6075 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6076 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6077 next_block_index = 1;
6080 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6082 /* The top-level BLOCK isn't numbered at all. */
6083 for (i = 1; i < n_blocks; ++i)
6084 /* We number the blocks from two. */
6085 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6087 free (block_vector);
6092 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6095 debug_find_var_in_block_tree (var, block)
6101 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6105 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6107 tree ret = debug_find_var_in_block_tree (var, t);
6115 /* Allocate a function structure and reset its contents to the defaults. */
6118 prepare_function_start ()
6120 cfun = (struct function *) ggc_alloc_cleared (sizeof (struct function));
6122 init_stmt_for_function ();
6123 init_eh_for_function ();
6125 cse_not_expected = ! optimize;
6127 /* Caller save not needed yet. */
6128 caller_save_needed = 0;
6130 /* No stack slots have been made yet. */
6131 stack_slot_list = 0;
6133 current_function_has_nonlocal_label = 0;
6134 current_function_has_nonlocal_goto = 0;
6136 /* There is no stack slot for handling nonlocal gotos. */
6137 nonlocal_goto_handler_slots = 0;
6138 nonlocal_goto_stack_level = 0;
6140 /* No labels have been declared for nonlocal use. */
6141 nonlocal_labels = 0;
6142 nonlocal_goto_handler_labels = 0;
6144 /* No function calls so far in this function. */
6145 function_call_count = 0;
6147 /* No parm regs have been allocated.
6148 (This is important for output_inline_function.) */
6149 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6151 /* Initialize the RTL mechanism. */
6154 /* Initialize the queue of pending postincrement and postdecrements,
6155 and some other info in expr.c. */
6158 /* We haven't done register allocation yet. */
6161 init_varasm_status (cfun);
6163 /* Clear out data used for inlining. */
6164 cfun->inlinable = 0;
6165 cfun->original_decl_initial = 0;
6166 cfun->original_arg_vector = 0;
6168 cfun->stack_alignment_needed = STACK_BOUNDARY;
6169 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6171 /* Set if a call to setjmp is seen. */
6172 current_function_calls_setjmp = 0;
6174 /* Set if a call to longjmp is seen. */
6175 current_function_calls_longjmp = 0;
6177 current_function_calls_alloca = 0;
6178 current_function_contains_functions = 0;
6179 current_function_is_leaf = 0;
6180 current_function_nothrow = 0;
6181 current_function_sp_is_unchanging = 0;
6182 current_function_uses_only_leaf_regs = 0;
6183 current_function_has_computed_jump = 0;
6184 current_function_is_thunk = 0;
6186 current_function_returns_pcc_struct = 0;
6187 current_function_returns_struct = 0;
6188 current_function_epilogue_delay_list = 0;
6189 current_function_uses_const_pool = 0;
6190 current_function_uses_pic_offset_table = 0;
6191 current_function_cannot_inline = 0;
6193 /* We have not yet needed to make a label to jump to for tail-recursion. */
6194 tail_recursion_label = 0;
6196 /* We haven't had a need to make a save area for ap yet. */
6197 arg_pointer_save_area = 0;
6199 /* No stack slots allocated yet. */
6202 /* No SAVE_EXPRs in this function yet. */
6205 /* No RTL_EXPRs in this function yet. */
6208 /* Set up to allocate temporaries. */
6211 /* Indicate that we need to distinguish between the return value of the
6212 present function and the return value of a function being called. */
6213 rtx_equal_function_value_matters = 1;
6215 /* Indicate that we have not instantiated virtual registers yet. */
6216 virtuals_instantiated = 0;
6218 /* Indicate that we want CONCATs now. */
6219 generating_concat_p = 1;
6221 /* Indicate we have no need of a frame pointer yet. */
6222 frame_pointer_needed = 0;
6224 /* By default assume not varargs or stdarg. */
6225 current_function_varargs = 0;
6226 current_function_stdarg = 0;
6228 /* We haven't made any trampolines for this function yet. */
6229 trampoline_list = 0;
6231 init_pending_stack_adjust ();
6232 inhibit_defer_pop = 0;
6234 current_function_outgoing_args_size = 0;
6236 if (init_lang_status)
6237 (*init_lang_status) (cfun);
6238 if (init_machine_status)
6239 (*init_machine_status) (cfun);
6242 /* Initialize the rtl expansion mechanism so that we can do simple things
6243 like generate sequences. This is used to provide a context during global
6244 initialization of some passes. */
6246 init_dummy_function_start ()
6248 prepare_function_start ();
6251 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6252 and initialize static variables for generating RTL for the statements
6256 init_function_start (subr, filename, line)
6258 const char *filename;
6261 prepare_function_start ();
6263 current_function_name = (*lang_hooks.decl_printable_name) (subr, 2);
6266 /* Nonzero if this is a nested function that uses a static chain. */
6268 current_function_needs_context
6269 = (decl_function_context (current_function_decl) != 0
6270 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6272 /* Within function body, compute a type's size as soon it is laid out. */
6273 immediate_size_expand++;
6275 /* Prevent ever trying to delete the first instruction of a function.
6276 Also tell final how to output a linenum before the function prologue.
6277 Note linenums could be missing, e.g. when compiling a Java .class file. */
6279 emit_line_note (filename, line);
6281 /* Make sure first insn is a note even if we don't want linenums.
6282 This makes sure the first insn will never be deleted.
6283 Also, final expects a note to appear there. */
6284 emit_note (NULL, NOTE_INSN_DELETED);
6286 /* Set flags used by final.c. */
6287 if (aggregate_value_p (DECL_RESULT (subr)))
6289 #ifdef PCC_STATIC_STRUCT_RETURN
6290 current_function_returns_pcc_struct = 1;
6292 current_function_returns_struct = 1;
6295 /* Warn if this value is an aggregate type,
6296 regardless of which calling convention we are using for it. */
6297 if (warn_aggregate_return
6298 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6299 warning ("function returns an aggregate");
6301 current_function_returns_pointer
6302 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
6305 /* Make sure all values used by the optimization passes have sane
6308 init_function_for_compilation ()
6312 /* No prologue/epilogue insns yet. */
6313 VARRAY_GROW (prologue, 0);
6314 VARRAY_GROW (epilogue, 0);
6315 VARRAY_GROW (sibcall_epilogue, 0);
6318 /* Indicate that the current function uses extra args
6319 not explicitly mentioned in the argument list in any fashion. */
6324 current_function_varargs = 1;
6327 /* Expand a call to __main at the beginning of a possible main function. */
6329 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6330 #undef HAS_INIT_SECTION
6331 #define HAS_INIT_SECTION
6335 expand_main_function ()
6337 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6338 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6340 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6344 /* Forcibly align the stack. */
6345 #ifdef STACK_GROWS_DOWNWARD
6346 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6347 stack_pointer_rtx, 1, OPTAB_WIDEN);
6349 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6350 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6351 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6352 stack_pointer_rtx, 1, OPTAB_WIDEN);
6354 if (tmp != stack_pointer_rtx)
6355 emit_move_insn (stack_pointer_rtx, tmp);
6357 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6358 tmp = force_reg (Pmode, const0_rtx);
6359 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6360 seq = gen_sequence ();
6363 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6364 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6367 emit_insn_before (seq, tmp);
6373 #ifndef HAS_INIT_SECTION
6374 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), LCT_NORMAL,
6379 extern struct obstack permanent_obstack;
6381 /* The PENDING_SIZES represent the sizes of variable-sized types.
6382 Create RTL for the various sizes now (using temporary variables),
6383 so that we can refer to the sizes from the RTL we are generating
6384 for the current function. The PENDING_SIZES are a TREE_LIST. The
6385 TREE_VALUE of each node is a SAVE_EXPR. */
6388 expand_pending_sizes (pending_sizes)
6393 /* Evaluate now the sizes of any types declared among the arguments. */
6394 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6396 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6397 /* Flush the queue in case this parameter declaration has
6403 /* Start the RTL for a new function, and set variables used for
6405 SUBR is the FUNCTION_DECL node.
6406 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6407 the function's parameters, which must be run at any return statement. */
6410 expand_function_start (subr, parms_have_cleanups)
6412 int parms_have_cleanups;
6415 rtx last_ptr = NULL_RTX;
6417 /* Make sure volatile mem refs aren't considered
6418 valid operands of arithmetic insns. */
6419 init_recog_no_volatile ();
6421 current_function_instrument_entry_exit
6422 = (flag_instrument_function_entry_exit
6423 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6425 current_function_profile
6427 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6429 current_function_limit_stack
6430 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6432 /* If function gets a static chain arg, store it in the stack frame.
6433 Do this first, so it gets the first stack slot offset. */
6434 if (current_function_needs_context)
6436 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6438 /* Delay copying static chain if it is not a register to avoid
6439 conflicts with regs used for parameters. */
6440 if (! SMALL_REGISTER_CLASSES
6441 || GET_CODE (static_chain_incoming_rtx) == REG)
6442 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6445 /* If the parameters of this function need cleaning up, get a label
6446 for the beginning of the code which executes those cleanups. This must
6447 be done before doing anything with return_label. */
6448 if (parms_have_cleanups)
6449 cleanup_label = gen_label_rtx ();
6453 /* Make the label for return statements to jump to. Do not special
6454 case machines with special return instructions -- they will be
6455 handled later during jump, ifcvt, or epilogue creation. */
6456 return_label = gen_label_rtx ();
6458 /* Initialize rtx used to return the value. */
6459 /* Do this before assign_parms so that we copy the struct value address
6460 before any library calls that assign parms might generate. */
6462 /* Decide whether to return the value in memory or in a register. */
6463 if (aggregate_value_p (DECL_RESULT (subr)))
6465 /* Returning something that won't go in a register. */
6466 rtx value_address = 0;
6468 #ifdef PCC_STATIC_STRUCT_RETURN
6469 if (current_function_returns_pcc_struct)
6471 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6472 value_address = assemble_static_space (size);
6477 /* Expect to be passed the address of a place to store the value.
6478 If it is passed as an argument, assign_parms will take care of
6480 if (struct_value_incoming_rtx)
6482 value_address = gen_reg_rtx (Pmode);
6483 emit_move_insn (value_address, struct_value_incoming_rtx);
6488 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6489 set_mem_attributes (x, DECL_RESULT (subr), 1);
6490 SET_DECL_RTL (DECL_RESULT (subr), x);
6493 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6494 /* If return mode is void, this decl rtl should not be used. */
6495 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6498 /* Compute the return values into a pseudo reg, which we will copy
6499 into the true return register after the cleanups are done. */
6501 /* In order to figure out what mode to use for the pseudo, we
6502 figure out what the mode of the eventual return register will
6503 actually be, and use that. */
6505 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6508 /* Structures that are returned in registers are not aggregate_value_p,
6509 so we may see a PARALLEL. Don't play pseudo games with this. */
6510 if (! REG_P (hard_reg))
6511 SET_DECL_RTL (DECL_RESULT (subr), hard_reg);
6514 /* Create the pseudo. */
6515 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6517 /* Needed because we may need to move this to memory
6518 in case it's a named return value whose address is taken. */
6519 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6523 /* Initialize rtx for parameters and local variables.
6524 In some cases this requires emitting insns. */
6526 assign_parms (subr);
6528 /* Copy the static chain now if it wasn't a register. The delay is to
6529 avoid conflicts with the parameter passing registers. */
6531 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6532 if (GET_CODE (static_chain_incoming_rtx) != REG)
6533 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6535 /* The following was moved from init_function_start.
6536 The move is supposed to make sdb output more accurate. */
6537 /* Indicate the beginning of the function body,
6538 as opposed to parm setup. */
6539 emit_note (NULL, NOTE_INSN_FUNCTION_BEG);
6541 if (GET_CODE (get_last_insn ()) != NOTE)
6542 emit_note (NULL, NOTE_INSN_DELETED);
6543 parm_birth_insn = get_last_insn ();
6545 context_display = 0;
6546 if (current_function_needs_context)
6548 /* Fetch static chain values for containing functions. */
6549 tem = decl_function_context (current_function_decl);
6550 /* Copy the static chain pointer into a pseudo. If we have
6551 small register classes, copy the value from memory if
6552 static_chain_incoming_rtx is a REG. */
6555 /* If the static chain originally came in a register, put it back
6556 there, then move it out in the next insn. The reason for
6557 this peculiar code is to satisfy function integration. */
6558 if (SMALL_REGISTER_CLASSES
6559 && GET_CODE (static_chain_incoming_rtx) == REG)
6560 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6561 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6566 tree rtlexp = make_node (RTL_EXPR);
6568 RTL_EXPR_RTL (rtlexp) = last_ptr;
6569 context_display = tree_cons (tem, rtlexp, context_display);
6570 tem = decl_function_context (tem);
6573 /* Chain thru stack frames, assuming pointer to next lexical frame
6574 is found at the place we always store it. */
6575 #ifdef FRAME_GROWS_DOWNWARD
6576 last_ptr = plus_constant (last_ptr,
6577 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6579 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6580 set_mem_alias_set (last_ptr, get_frame_alias_set ());
6581 last_ptr = copy_to_reg (last_ptr);
6583 /* If we are not optimizing, ensure that we know that this
6584 piece of context is live over the entire function. */
6586 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6591 if (current_function_instrument_entry_exit)
6593 rtx fun = DECL_RTL (current_function_decl);
6594 if (GET_CODE (fun) == MEM)
6595 fun = XEXP (fun, 0);
6598 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode,
6600 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6602 hard_frame_pointer_rtx),
6607 if (current_function_profile)
6608 PROFILE_HOOK (profile_label_no);
6611 /* After the display initializations is where the tail-recursion label
6612 should go, if we end up needing one. Ensure we have a NOTE here
6613 since some things (like trampolines) get placed before this. */
6614 tail_recursion_reentry = emit_note (NULL, NOTE_INSN_DELETED);
6616 /* Evaluate now the sizes of any types declared among the arguments. */
6617 expand_pending_sizes (nreverse (get_pending_sizes ()));
6619 /* Make sure there is a line number after the function entry setup code. */
6620 force_next_line_note ();
6623 /* Undo the effects of init_dummy_function_start. */
6625 expand_dummy_function_end ()
6627 /* End any sequences that failed to be closed due to syntax errors. */
6628 while (in_sequence_p ())
6631 /* Outside function body, can't compute type's actual size
6632 until next function's body starts. */
6634 free_after_parsing (cfun);
6635 free_after_compilation (cfun);
6639 /* Call DOIT for each hard register used as a return value from
6640 the current function. */
6643 diddle_return_value (doit, arg)
6644 void (*doit) PARAMS ((rtx, void *));
6647 rtx outgoing = current_function_return_rtx;
6652 if (GET_CODE (outgoing) == REG)
6653 (*doit) (outgoing, arg);
6654 else if (GET_CODE (outgoing) == PARALLEL)
6658 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6660 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6662 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6669 do_clobber_return_reg (reg, arg)
6671 void *arg ATTRIBUTE_UNUSED;
6673 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6677 clobber_return_register ()
6679 diddle_return_value (do_clobber_return_reg, NULL);
6681 /* In case we do use pseudo to return value, clobber it too. */
6682 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6684 tree decl_result = DECL_RESULT (current_function_decl);
6685 rtx decl_rtl = DECL_RTL (decl_result);
6686 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6688 do_clobber_return_reg (decl_rtl, NULL);
6694 do_use_return_reg (reg, arg)
6696 void *arg ATTRIBUTE_UNUSED;
6698 emit_insn (gen_rtx_USE (VOIDmode, reg));
6702 use_return_register ()
6704 diddle_return_value (do_use_return_reg, NULL);
6707 /* Generate RTL for the end of the current function.
6708 FILENAME and LINE are the current position in the source file.
6710 It is up to language-specific callers to do cleanups for parameters--
6711 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6714 expand_function_end (filename, line, end_bindings)
6715 const char *filename;
6722 #ifdef TRAMPOLINE_TEMPLATE
6723 static rtx initial_trampoline;
6726 finish_expr_for_function ();
6728 /* If arg_pointer_save_area was referenced only from a nested
6729 function, we will not have initialized it yet. Do that now. */
6730 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6731 get_arg_pointer_save_area (cfun);
6733 #ifdef NON_SAVING_SETJMP
6734 /* Don't put any variables in registers if we call setjmp
6735 on a machine that fails to restore the registers. */
6736 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6738 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6739 setjmp_protect (DECL_INITIAL (current_function_decl));
6741 setjmp_protect_args ();
6745 /* Initialize any trampolines required by this function. */
6746 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6748 tree function = TREE_PURPOSE (link);
6749 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6750 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6751 #ifdef TRAMPOLINE_TEMPLATE
6756 #ifdef TRAMPOLINE_TEMPLATE
6757 /* First make sure this compilation has a template for
6758 initializing trampolines. */
6759 if (initial_trampoline == 0)
6762 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6763 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
6765 ggc_add_rtx_root (&initial_trampoline, 1);
6769 /* Generate insns to initialize the trampoline. */
6771 tramp = round_trampoline_addr (XEXP (tramp, 0));
6772 #ifdef TRAMPOLINE_TEMPLATE
6773 blktramp = replace_equiv_address (initial_trampoline, tramp);
6774 emit_block_move (blktramp, initial_trampoline,
6775 GEN_INT (TRAMPOLINE_SIZE));
6777 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6781 /* Put those insns at entry to the containing function (this one). */
6782 emit_insns_before (seq, tail_recursion_reentry);
6785 /* If we are doing stack checking and this function makes calls,
6786 do a stack probe at the start of the function to ensure we have enough
6787 space for another stack frame. */
6788 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6792 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6793 if (GET_CODE (insn) == CALL_INSN)
6796 probe_stack_range (STACK_CHECK_PROTECT,
6797 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6800 emit_insns_before (seq, tail_recursion_reentry);
6805 /* Warn about unused parms if extra warnings were specified. */
6806 /* Either ``-W -Wunused'' or ``-Wunused-parameter'' enables this
6807 warning. WARN_UNUSED_PARAMETER is negative when set by
6809 if (warn_unused_parameter > 0
6810 || (warn_unused_parameter < 0 && extra_warnings))
6814 for (decl = DECL_ARGUMENTS (current_function_decl);
6815 decl; decl = TREE_CHAIN (decl))
6816 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6817 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6818 warning_with_decl (decl, "unused parameter `%s'");
6821 /* Delete handlers for nonlocal gotos if nothing uses them. */
6822 if (nonlocal_goto_handler_slots != 0
6823 && ! current_function_has_nonlocal_label)
6826 /* End any sequences that failed to be closed due to syntax errors. */
6827 while (in_sequence_p ())
6830 /* Outside function body, can't compute type's actual size
6831 until next function's body starts. */
6832 immediate_size_expand--;
6834 clear_pending_stack_adjust ();
6835 do_pending_stack_adjust ();
6837 /* Mark the end of the function body.
6838 If control reaches this insn, the function can drop through
6839 without returning a value. */
6840 emit_note (NULL, NOTE_INSN_FUNCTION_END);
6842 /* Must mark the last line number note in the function, so that the test
6843 coverage code can avoid counting the last line twice. This just tells
6844 the code to ignore the immediately following line note, since there
6845 already exists a copy of this note somewhere above. This line number
6846 note is still needed for debugging though, so we can't delete it. */
6847 if (flag_test_coverage)
6848 emit_note (NULL, NOTE_INSN_REPEATED_LINE_NUMBER);
6850 /* Output a linenumber for the end of the function.
6851 SDB depends on this. */
6852 emit_line_note_force (filename, line);
6854 /* Before the return label (if any), clobber the return
6855 registers so that they are not propagated live to the rest of
6856 the function. This can only happen with functions that drop
6857 through; if there had been a return statement, there would
6858 have either been a return rtx, or a jump to the return label.
6860 We delay actual code generation after the current_function_value_rtx
6862 clobber_after = get_last_insn ();
6864 /* Output the label for the actual return from the function,
6865 if one is expected. This happens either because a function epilogue
6866 is used instead of a return instruction, or because a return was done
6867 with a goto in order to run local cleanups, or because of pcc-style
6868 structure returning. */
6870 emit_label (return_label);
6872 /* C++ uses this. */
6874 expand_end_bindings (0, 0, 0);
6876 if (current_function_instrument_entry_exit)
6878 rtx fun = DECL_RTL (current_function_decl);
6879 if (GET_CODE (fun) == MEM)
6880 fun = XEXP (fun, 0);
6883 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode,
6885 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6887 hard_frame_pointer_rtx),
6891 /* Let except.c know where it should emit the call to unregister
6892 the function context for sjlj exceptions. */
6893 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
6894 sjlj_emit_function_exit_after (get_last_insn ());
6896 /* If we had calls to alloca, and this machine needs
6897 an accurate stack pointer to exit the function,
6898 insert some code to save and restore the stack pointer. */
6899 #ifdef EXIT_IGNORE_STACK
6900 if (! EXIT_IGNORE_STACK)
6902 if (current_function_calls_alloca)
6906 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6907 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6910 /* If scalar return value was computed in a pseudo-reg, or was a named
6911 return value that got dumped to the stack, copy that to the hard
6913 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6915 tree decl_result = DECL_RESULT (current_function_decl);
6916 rtx decl_rtl = DECL_RTL (decl_result);
6918 if (REG_P (decl_rtl)
6919 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
6920 : DECL_REGISTER (decl_result))
6924 #ifdef FUNCTION_OUTGOING_VALUE
6925 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
6926 current_function_decl);
6928 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
6929 current_function_decl);
6931 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
6933 /* If this is a BLKmode structure being returned in registers,
6934 then use the mode computed in expand_return. Note that if
6935 decl_rtl is memory, then its mode may have been changed,
6936 but that current_function_return_rtx has not. */
6937 if (GET_MODE (real_decl_rtl) == BLKmode)
6938 PUT_MODE (real_decl_rtl, GET_MODE (current_function_return_rtx));
6940 /* If a named return value dumped decl_return to memory, then
6941 we may need to re-do the PROMOTE_MODE signed/unsigned
6943 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
6945 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
6947 #ifdef PROMOTE_FUNCTION_RETURN
6948 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
6952 convert_move (real_decl_rtl, decl_rtl, unsignedp);
6954 else if (GET_CODE (real_decl_rtl) == PARALLEL)
6955 emit_group_load (real_decl_rtl, decl_rtl,
6956 int_size_in_bytes (TREE_TYPE (decl_result)));
6958 emit_move_insn (real_decl_rtl, decl_rtl);
6960 /* The delay slot scheduler assumes that current_function_return_rtx
6961 holds the hard register containing the return value, not a
6962 temporary pseudo. */
6963 current_function_return_rtx = real_decl_rtl;
6967 /* If returning a structure, arrange to return the address of the value
6968 in a place where debuggers expect to find it.
6970 If returning a structure PCC style,
6971 the caller also depends on this value.
6972 And current_function_returns_pcc_struct is not necessarily set. */
6973 if (current_function_returns_struct
6974 || current_function_returns_pcc_struct)
6977 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6978 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6979 #ifdef FUNCTION_OUTGOING_VALUE
6981 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6982 current_function_decl);
6985 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
6988 /* Mark this as a function return value so integrate will delete the
6989 assignment and USE below when inlining this function. */
6990 REG_FUNCTION_VALUE_P (outgoing) = 1;
6992 #ifdef POINTERS_EXTEND_UNSIGNED
6993 /* The address may be ptr_mode and OUTGOING may be Pmode. */
6994 if (GET_MODE (outgoing) != GET_MODE (value_address))
6995 value_address = convert_memory_address (GET_MODE (outgoing),
6999 emit_move_insn (outgoing, value_address);
7001 /* Show return register used to hold result (in this case the address
7003 current_function_return_rtx = outgoing;
7006 /* If this is an implementation of throw, do what's necessary to
7007 communicate between __builtin_eh_return and the epilogue. */
7008 expand_eh_return ();
7010 /* Emit the actual code to clobber return register. */
7015 clobber_return_register ();
7016 seq = gen_sequence ();
7019 after = emit_insn_after (seq, clobber_after);
7021 if (clobber_after != after)
7022 cfun->x_clobber_return_insn = after;
7025 /* ??? This should no longer be necessary since stupid is no longer with
7026 us, but there are some parts of the compiler (eg reload_combine, and
7027 sh mach_dep_reorg) that still try and compute their own lifetime info
7028 instead of using the general framework. */
7029 use_return_register ();
7031 /* Fix up any gotos that jumped out to the outermost
7032 binding level of the function.
7033 Must follow emitting RETURN_LABEL. */
7035 /* If you have any cleanups to do at this point,
7036 and they need to create temporary variables,
7037 then you will lose. */
7038 expand_fixups (get_insns ());
7042 get_arg_pointer_save_area (f)
7045 rtx ret = f->x_arg_pointer_save_area;
7049 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
7050 f->x_arg_pointer_save_area = ret;
7053 if (f == cfun && ! f->arg_pointer_save_area_init)
7057 /* Save the arg pointer at the beginning of the function. The
7058 generated stack slot may not be a valid memory address, so we
7059 have to check it and fix it if necessary. */
7061 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
7062 seq = gen_sequence ();
7065 push_topmost_sequence ();
7066 emit_insn_after (seq, get_insns ());
7067 pop_topmost_sequence ();
7073 /* Extend a vector that records the INSN_UIDs of INSNS (either a
7074 sequence or a single insn). */
7077 record_insns (insns, vecp)
7081 if (GET_CODE (insns) == SEQUENCE)
7083 int len = XVECLEN (insns, 0);
7084 int i = VARRAY_SIZE (*vecp);
7086 VARRAY_GROW (*vecp, i + len);
7089 VARRAY_INT (*vecp, i) = INSN_UID (XVECEXP (insns, 0, len));
7095 int i = VARRAY_SIZE (*vecp);
7096 VARRAY_GROW (*vecp, i + 1);
7097 VARRAY_INT (*vecp, i) = INSN_UID (insns);
7101 /* Determine how many INSN_UIDs in VEC are part of INSN. */
7104 contains (insn, vec)
7110 if (GET_CODE (insn) == INSN
7111 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7114 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7115 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7116 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7122 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7123 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7130 prologue_epilogue_contains (insn)
7133 if (contains (insn, prologue))
7135 if (contains (insn, epilogue))
7141 sibcall_epilogue_contains (insn)
7144 if (sibcall_epilogue)
7145 return contains (insn, sibcall_epilogue);
7150 /* Insert gen_return at the end of block BB. This also means updating
7151 block_for_insn appropriately. */
7154 emit_return_into_block (bb, line_note)
7160 p = NEXT_INSN (bb->end);
7161 end = emit_jump_insn_after (gen_return (), bb->end);
7163 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
7164 NOTE_LINE_NUMBER (line_note), PREV_INSN (bb->end));
7166 #endif /* HAVE_return */
7168 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7170 /* These functions convert the epilogue into a variant that does not modify the
7171 stack pointer. This is used in cases where a function returns an object
7172 whose size is not known until it is computed. The called function leaves the
7173 object on the stack, leaves the stack depressed, and returns a pointer to
7176 What we need to do is track all modifications and references to the stack
7177 pointer, deleting the modifications and changing the references to point to
7178 the location the stack pointer would have pointed to had the modifications
7181 These functions need to be portable so we need to make as few assumptions
7182 about the epilogue as we can. However, the epilogue basically contains
7183 three things: instructions to reset the stack pointer, instructions to
7184 reload registers, possibly including the frame pointer, and an
7185 instruction to return to the caller.
7187 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7188 We also make no attempt to validate the insns we make since if they are
7189 invalid, we probably can't do anything valid. The intent is that these
7190 routines get "smarter" as more and more machines start to use them and
7191 they try operating on different epilogues.
7193 We use the following structure to track what the part of the epilogue that
7194 we've already processed has done. We keep two copies of the SP equivalence,
7195 one for use during the insn we are processing and one for use in the next
7196 insn. The difference is because one part of a PARALLEL may adjust SP
7197 and the other may use it. */
7201 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7202 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7203 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7204 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7205 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7206 should be set to once we no longer need
7210 static void handle_epilogue_set PARAMS ((rtx, struct epi_info *));
7211 static void emit_equiv_load PARAMS ((struct epi_info *));
7213 /* Modify SEQ, a SEQUENCE that is part of the epilogue, to no modifications
7214 to the stack pointer. Return the new sequence. */
7217 keep_stack_depressed (seq)
7221 struct epi_info info;
7223 /* If the epilogue is just a single instruction, it ust be OK as is. */
7225 if (GET_CODE (seq) != SEQUENCE)
7228 /* Otherwise, start a sequence, initialize the information we have, and
7229 process all the insns we were given. */
7232 info.sp_equiv_reg = stack_pointer_rtx;
7234 info.equiv_reg_src = 0;
7236 for (i = 0; i < XVECLEN (seq, 0); i++)
7238 rtx insn = XVECEXP (seq, 0, i);
7246 /* If this insn references the register that SP is equivalent to and
7247 we have a pending load to that register, we must force out the load
7248 first and then indicate we no longer know what SP's equivalent is. */
7249 if (info.equiv_reg_src != 0
7250 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7252 emit_equiv_load (&info);
7253 info.sp_equiv_reg = 0;
7256 info.new_sp_equiv_reg = info.sp_equiv_reg;
7257 info.new_sp_offset = info.sp_offset;
7259 /* If this is a (RETURN) and the return address is on the stack,
7260 update the address and change to an indirect jump. */
7261 if (GET_CODE (PATTERN (insn)) == RETURN
7262 || (GET_CODE (PATTERN (insn)) == PARALLEL
7263 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7265 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7267 HOST_WIDE_INT offset = 0;
7268 rtx jump_insn, jump_set;
7270 /* If the return address is in a register, we can emit the insn
7271 unchanged. Otherwise, it must be a MEM and we see what the
7272 base register and offset are. In any case, we have to emit any
7273 pending load to the equivalent reg of SP, if any. */
7274 if (GET_CODE (retaddr) == REG)
7276 emit_equiv_load (&info);
7280 else if (GET_CODE (retaddr) == MEM
7281 && GET_CODE (XEXP (retaddr, 0)) == REG)
7282 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7283 else if (GET_CODE (retaddr) == MEM
7284 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7285 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7286 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7288 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7289 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7294 /* If the base of the location containing the return pointer
7295 is SP, we must update it with the replacement address. Otherwise,
7296 just build the necessary MEM. */
7297 retaddr = plus_constant (base, offset);
7298 if (base == stack_pointer_rtx)
7299 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7300 plus_constant (info.sp_equiv_reg,
7303 retaddr = gen_rtx_MEM (Pmode, retaddr);
7305 /* If there is a pending load to the equivalent register for SP
7306 and we reference that register, we must load our address into
7307 a scratch register and then do that load. */
7308 if (info.equiv_reg_src
7309 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7314 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7315 if (HARD_REGNO_MODE_OK (regno, Pmode)
7316 && !fixed_regs[regno]
7317 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7318 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7320 && !refers_to_regno_p (regno,
7321 regno + HARD_REGNO_NREGS (regno,
7323 info.equiv_reg_src, NULL))
7326 if (regno == FIRST_PSEUDO_REGISTER)
7329 reg = gen_rtx_REG (Pmode, regno);
7330 emit_move_insn (reg, retaddr);
7334 emit_equiv_load (&info);
7335 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7337 /* Show the SET in the above insn is a RETURN. */
7338 jump_set = single_set (jump_insn);
7342 SET_IS_RETURN_P (jump_set) = 1;
7345 /* If SP is not mentioned in the pattern and its equivalent register, if
7346 any, is not modified, just emit it. Otherwise, if neither is set,
7347 replace the reference to SP and emit the insn. If none of those are
7348 true, handle each SET individually. */
7349 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7350 && (info.sp_equiv_reg == stack_pointer_rtx
7351 || !reg_set_p (info.sp_equiv_reg, insn)))
7353 else if (! reg_set_p (stack_pointer_rtx, insn)
7354 && (info.sp_equiv_reg == stack_pointer_rtx
7355 || !reg_set_p (info.sp_equiv_reg, insn)))
7357 if (! validate_replace_rtx (stack_pointer_rtx,
7358 plus_constant (info.sp_equiv_reg,
7365 else if (GET_CODE (PATTERN (insn)) == SET)
7366 handle_epilogue_set (PATTERN (insn), &info);
7367 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7369 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7370 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7371 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7376 info.sp_equiv_reg = info.new_sp_equiv_reg;
7377 info.sp_offset = info.new_sp_offset;
7380 seq = gen_sequence ();
7385 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7386 structure that contains information about what we've seen so far. We
7387 process this SET by either updating that data or by emitting one or
7391 handle_epilogue_set (set, p)
7395 /* First handle the case where we are setting SP. Record what it is being
7396 set from. If unknown, abort. */
7397 if (reg_set_p (stack_pointer_rtx, set))
7399 if (SET_DEST (set) != stack_pointer_rtx)
7402 if (GET_CODE (SET_SRC (set)) == PLUS
7403 && GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7405 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7406 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7409 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7411 /* If we are adjusting SP, we adjust from the old data. */
7412 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7414 p->new_sp_equiv_reg = p->sp_equiv_reg;
7415 p->new_sp_offset += p->sp_offset;
7418 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7424 /* Next handle the case where we are setting SP's equivalent register.
7425 If we already have a value to set it to, abort. We could update, but
7426 there seems little point in handling that case. Note that we have
7427 to allow for the case where we are setting the register set in
7428 the previous part of a PARALLEL inside a single insn. But use the
7429 old offset for any updates within this insn. */
7430 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7432 if (!rtx_equal_p (p->new_sp_equiv_reg, SET_DEST (set))
7433 || p->equiv_reg_src != 0)
7437 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7438 plus_constant (p->sp_equiv_reg,
7442 /* Otherwise, replace any references to SP in the insn to its new value
7443 and emit the insn. */
7446 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7447 plus_constant (p->sp_equiv_reg,
7449 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7450 plus_constant (p->sp_equiv_reg,
7456 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7462 if (p->equiv_reg_src != 0)
7463 emit_move_insn (p->sp_equiv_reg, p->equiv_reg_src);
7465 p->equiv_reg_src = 0;
7469 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7470 this into place with notes indicating where the prologue ends and where
7471 the epilogue begins. Update the basic block information when possible. */
7474 thread_prologue_and_epilogue_insns (f)
7475 rtx f ATTRIBUTE_UNUSED;
7479 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7482 #ifdef HAVE_prologue
7483 rtx prologue_end = NULL_RTX;
7485 #if defined (HAVE_epilogue) || defined(HAVE_return)
7486 rtx epilogue_end = NULL_RTX;
7489 #ifdef HAVE_prologue
7493 seq = gen_prologue ();
7496 /* Retain a map of the prologue insns. */
7497 if (GET_CODE (seq) != SEQUENCE)
7499 record_insns (seq, &prologue);
7500 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
7502 seq = gen_sequence ();
7505 /* Can't deal with multiple successors of the entry block
7506 at the moment. Function should always have at least one
7508 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7511 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7516 /* If the exit block has no non-fake predecessors, we don't need
7518 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7519 if ((e->flags & EDGE_FAKE) == 0)
7525 if (optimize && HAVE_return)
7527 /* If we're allowed to generate a simple return instruction,
7528 then by definition we don't need a full epilogue. Examine
7529 the block that falls through to EXIT. If it does not
7530 contain any code, examine its predecessors and try to
7531 emit (conditional) return instructions. */
7537 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7538 if (e->flags & EDGE_FALLTHRU)
7544 /* Verify that there are no active instructions in the last block. */
7546 while (label && GET_CODE (label) != CODE_LABEL)
7548 if (active_insn_p (label))
7550 label = PREV_INSN (label);
7553 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7555 rtx epilogue_line_note = NULL_RTX;
7557 /* Locate the line number associated with the closing brace,
7558 if we can find one. */
7559 for (seq = get_last_insn ();
7560 seq && ! active_insn_p (seq);
7561 seq = PREV_INSN (seq))
7562 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7564 epilogue_line_note = seq;
7568 for (e = last->pred; e; e = e_next)
7570 basic_block bb = e->src;
7573 e_next = e->pred_next;
7574 if (bb == ENTRY_BLOCK_PTR)
7578 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7581 /* If we have an unconditional jump, we can replace that
7582 with a simple return instruction. */
7583 if (simplejump_p (jump))
7585 emit_return_into_block (bb, epilogue_line_note);
7589 /* If we have a conditional jump, we can try to replace
7590 that with a conditional return instruction. */
7591 else if (condjump_p (jump))
7595 ret = SET_SRC (PATTERN (jump));
7596 if (GET_CODE (XEXP (ret, 1)) == LABEL_REF)
7597 loc = &XEXP (ret, 1);
7599 loc = &XEXP (ret, 2);
7600 ret = gen_rtx_RETURN (VOIDmode);
7602 if (! validate_change (jump, loc, ret, 0))
7604 if (JUMP_LABEL (jump))
7605 LABEL_NUSES (JUMP_LABEL (jump))--;
7607 /* If this block has only one successor, it both jumps
7608 and falls through to the fallthru block, so we can't
7610 if (bb->succ->succ_next == NULL)
7616 /* Fix up the CFG for the successful change we just made. */
7617 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7620 /* Emit a return insn for the exit fallthru block. Whether
7621 this is still reachable will be determined later. */
7623 emit_barrier_after (last->end);
7624 emit_return_into_block (last, epilogue_line_note);
7625 epilogue_end = last->end;
7626 last->succ->flags &= ~EDGE_FALLTHRU;
7631 #ifdef HAVE_epilogue
7634 /* Find the edge that falls through to EXIT. Other edges may exist
7635 due to RETURN instructions, but those don't need epilogues.
7636 There really shouldn't be a mixture -- either all should have
7637 been converted or none, however... */
7639 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7640 if (e->flags & EDGE_FALLTHRU)
7646 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
7648 seq = gen_epilogue ();
7650 #ifdef INCOMING_RETURN_ADDR_RTX
7651 /* If this function returns with the stack depressed and we can support
7652 it, massage the epilogue to actually do that. */
7653 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7654 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7655 seq = keep_stack_depressed (seq);
7658 emit_jump_insn (seq);
7660 /* Retain a map of the epilogue insns. */
7661 if (GET_CODE (seq) != SEQUENCE)
7663 record_insns (seq, &epilogue);
7665 seq = gen_sequence ();
7668 insert_insn_on_edge (seq, e);
7675 commit_edge_insertions ();
7677 #ifdef HAVE_sibcall_epilogue
7678 /* Emit sibling epilogues before any sibling call sites. */
7679 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7681 basic_block bb = e->src;
7686 if (GET_CODE (insn) != CALL_INSN
7687 || ! SIBLING_CALL_P (insn))
7691 seq = gen_sibcall_epilogue ();
7694 i = PREV_INSN (insn);
7695 newinsn = emit_insn_before (seq, insn);
7697 /* Retain a map of the epilogue insns. Used in life analysis to
7698 avoid getting rid of sibcall epilogue insns. */
7699 record_insns (GET_CODE (seq) == SEQUENCE
7700 ? seq : newinsn, &sibcall_epilogue);
7704 #ifdef HAVE_prologue
7709 /* GDB handles `break f' by setting a breakpoint on the first
7710 line note after the prologue. Which means (1) that if
7711 there are line number notes before where we inserted the
7712 prologue we should move them, and (2) we should generate a
7713 note before the end of the first basic block, if there isn't
7716 ??? This behaviour is completely broken when dealing with
7717 multiple entry functions. We simply place the note always
7718 into first basic block and let alternate entry points
7722 for (insn = prologue_end; insn; insn = prev)
7724 prev = PREV_INSN (insn);
7725 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7727 /* Note that we cannot reorder the first insn in the
7728 chain, since rest_of_compilation relies on that
7729 remaining constant. */
7732 reorder_insns (insn, insn, prologue_end);
7736 /* Find the last line number note in the first block. */
7737 for (insn = BASIC_BLOCK (0)->end;
7738 insn != prologue_end && insn;
7739 insn = PREV_INSN (insn))
7740 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7743 /* If we didn't find one, make a copy of the first line number
7747 for (insn = next_active_insn (prologue_end);
7749 insn = PREV_INSN (insn))
7750 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7752 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7753 NOTE_LINE_NUMBER (insn),
7760 #ifdef HAVE_epilogue
7765 /* Similarly, move any line notes that appear after the epilogue.
7766 There is no need, however, to be quite so anal about the existence
7768 for (insn = epilogue_end; insn; insn = next)
7770 next = NEXT_INSN (insn);
7771 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7772 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7778 /* Reposition the prologue-end and epilogue-begin notes after instruction
7779 scheduling and delayed branch scheduling. */
7782 reposition_prologue_and_epilogue_notes (f)
7783 rtx f ATTRIBUTE_UNUSED;
7785 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7786 rtx insn, last, note;
7789 if ((len = VARRAY_SIZE (prologue)) > 0)
7793 /* Scan from the beginning until we reach the last prologue insn.
7794 We apparently can't depend on basic_block_{head,end} after
7796 for (insn = f; insn; insn = NEXT_INSN (insn))
7798 if (GET_CODE (insn) == NOTE)
7800 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7803 else if (contains (insn, prologue))
7815 /* Find the prologue-end note if we haven't already, and
7816 move it to just after the last prologue insn. */
7819 for (note = last; (note = NEXT_INSN (note));)
7820 if (GET_CODE (note) == NOTE
7821 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7825 next = NEXT_INSN (note);
7827 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7828 if (GET_CODE (last) == CODE_LABEL)
7829 last = NEXT_INSN (last);
7830 reorder_insns (note, note, last);
7834 if ((len = VARRAY_SIZE (epilogue)) > 0)
7838 /* Scan from the end until we reach the first epilogue insn.
7839 We apparently can't depend on basic_block_{head,end} after
7841 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
7843 if (GET_CODE (insn) == NOTE)
7845 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7848 else if (contains (insn, epilogue))
7858 /* Find the epilogue-begin note if we haven't already, and
7859 move it to just before the first epilogue insn. */
7862 for (note = insn; (note = PREV_INSN (note));)
7863 if (GET_CODE (note) == NOTE
7864 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7868 if (PREV_INSN (last) != note)
7869 reorder_insns (note, note, PREV_INSN (last));
7872 #endif /* HAVE_prologue or HAVE_epilogue */
7875 /* Mark P for GC. */
7878 mark_function_status (p)
7881 struct var_refs_queue *q;
7882 struct temp_slot *t;
7889 ggc_mark_rtx (p->arg_offset_rtx);
7891 if (p->x_parm_reg_stack_loc)
7892 for (i = p->x_max_parm_reg, r = p->x_parm_reg_stack_loc;
7896 ggc_mark_rtx (p->return_rtx);
7897 ggc_mark_rtx (p->x_cleanup_label);
7898 ggc_mark_rtx (p->x_return_label);
7899 ggc_mark_rtx (p->x_save_expr_regs);
7900 ggc_mark_rtx (p->x_stack_slot_list);
7901 ggc_mark_rtx (p->x_parm_birth_insn);
7902 ggc_mark_rtx (p->x_tail_recursion_label);
7903 ggc_mark_rtx (p->x_tail_recursion_reentry);
7904 ggc_mark_rtx (p->internal_arg_pointer);
7905 ggc_mark_rtx (p->x_arg_pointer_save_area);
7906 ggc_mark_tree (p->x_rtl_expr_chain);
7907 ggc_mark_rtx (p->x_last_parm_insn);
7908 ggc_mark_tree (p->x_context_display);
7909 ggc_mark_tree (p->x_trampoline_list);
7910 ggc_mark_rtx (p->epilogue_delay_list);
7911 ggc_mark_rtx (p->x_clobber_return_insn);
7913 for (t = p->x_temp_slots; t != 0; t = t->next)
7916 ggc_mark_rtx (t->slot);
7917 ggc_mark_rtx (t->address);
7918 ggc_mark_tree (t->rtl_expr);
7919 ggc_mark_tree (t->type);
7922 for (q = p->fixup_var_refs_queue; q != 0; q = q->next)
7925 ggc_mark_rtx (q->modified);
7928 ggc_mark_rtx (p->x_nonlocal_goto_handler_slots);
7929 ggc_mark_rtx (p->x_nonlocal_goto_handler_labels);
7930 ggc_mark_rtx (p->x_nonlocal_goto_stack_level);
7931 ggc_mark_tree (p->x_nonlocal_labels);
7933 mark_hard_reg_initial_vals (p);
7936 /* Mark the struct function pointed to by *ARG for GC, if it is not
7937 NULL. This is used to mark the current function and the outer
7941 maybe_mark_struct_function (arg)
7944 struct function *f = *(struct function **) arg;
7949 ggc_mark_struct_function (f);
7952 /* Mark a struct function * for GC. This is called from ggc-common.c. */
7955 ggc_mark_struct_function (f)
7959 ggc_mark_tree (f->decl);
7961 mark_function_status (f);
7962 mark_eh_status (f->eh);
7963 mark_stmt_status (f->stmt);
7964 mark_expr_status (f->expr);
7965 mark_emit_status (f->emit);
7966 mark_varasm_status (f->varasm);
7968 if (mark_machine_status)
7969 (*mark_machine_status) (f);
7970 if (mark_lang_status)
7971 (*mark_lang_status) (f);
7973 if (f->original_arg_vector)
7974 ggc_mark_rtvec ((rtvec) f->original_arg_vector);
7975 if (f->original_decl_initial)
7976 ggc_mark_tree (f->original_decl_initial);
7978 ggc_mark_struct_function (f->outer);
7981 /* Called once, at initialization, to initialize function.c. */
7984 init_function_once ()
7986 ggc_add_root (&cfun, 1, sizeof cfun, maybe_mark_struct_function);
7987 ggc_add_root (&outer_function_chain, 1, sizeof outer_function_chain,
7988 maybe_mark_struct_function);
7990 VARRAY_INT_INIT (prologue, 0, "prologue");
7991 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7992 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");