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, 2003 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register.
36 Call `put_var_into_stack' when you learn, belatedly, that a variable
37 previously given a pseudo-register must in fact go in the stack.
38 This function changes the DECL_RTL to be a stack slot instead of a reg
39 then scans all the RTL instructions so far generated to correct them. */
43 #include "coretypes.h"
53 #include "hard-reg-set.h"
54 #include "insn-config.h"
57 #include "basic-block.h"
62 #include "integrate.h"
63 #include "langhooks.h"
65 #ifndef TRAMPOLINE_ALIGNMENT
66 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
69 #ifndef LOCAL_ALIGNMENT
70 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
73 #ifndef STACK_ALIGNMENT_NEEDED
74 #define STACK_ALIGNMENT_NEEDED 1
77 /* Some systems use __main in a way incompatible with its use in gcc, in these
78 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
79 give the same symbol without quotes for an alternative entry point. You
80 must define both, or neither. */
82 #define NAME__MAIN "__main"
85 /* Round a value to the lowest integer less than it that is a multiple of
86 the required alignment. Avoid using division in case the value is
87 negative. Assume the alignment is a power of two. */
88 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
90 /* Similar, but round to the next highest integer that meets the
92 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
94 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
95 during rtl generation. If they are different register numbers, this is
96 always true. It may also be true if
97 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
98 generation. See fix_lexical_addr for details. */
100 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
101 #define NEED_SEPARATE_AP
104 /* Nonzero if function being compiled doesn't contain any calls
105 (ignoring the prologue and epilogue). This is set prior to
106 local register allocation and is valid for the remaining
108 int current_function_is_leaf;
110 /* Nonzero if function being compiled doesn't contain any instructions
111 that can throw an exception. This is set prior to final. */
113 int current_function_nothrow;
115 /* Nonzero if function being compiled doesn't modify the stack pointer
116 (ignoring the prologue and epilogue). This is only valid after
117 life_analysis has run. */
118 int current_function_sp_is_unchanging;
120 /* Nonzero if the function being compiled is a leaf function which only
121 uses leaf registers. This is valid after reload (specifically after
122 sched2) and is useful only if the port defines LEAF_REGISTERS. */
123 int current_function_uses_only_leaf_regs;
125 /* Nonzero once virtual register instantiation has been done.
126 assign_stack_local uses frame_pointer_rtx when this is nonzero.
127 calls.c:emit_library_call_value_1 uses it to set up
128 post-instantiation libcalls. */
129 int virtuals_instantiated;
131 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
132 static GTY(()) int funcdef_no;
134 /* These variables hold pointers to functions to create and destroy
135 target specific, per-function data structures. */
136 struct machine_function * (*init_machine_status) PARAMS ((void));
138 /* The FUNCTION_DECL for an inline function currently being expanded. */
139 tree inline_function_decl;
141 /* The currently compiled function. */
142 struct function *cfun = 0;
144 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
145 static GTY(()) varray_type prologue;
146 static GTY(()) varray_type epilogue;
148 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
150 static GTY(()) varray_type sibcall_epilogue;
152 /* In order to evaluate some expressions, such as function calls returning
153 structures in memory, we need to temporarily allocate stack locations.
154 We record each allocated temporary in the following structure.
156 Associated with each temporary slot is a nesting level. When we pop up
157 one level, all temporaries associated with the previous level are freed.
158 Normally, all temporaries are freed after the execution of the statement
159 in which they were created. However, if we are inside a ({...}) grouping,
160 the result may be in a temporary and hence must be preserved. If the
161 result could be in a temporary, we preserve it if we can determine which
162 one it is in. If we cannot determine which temporary may contain the
163 result, all temporaries are preserved. A temporary is preserved by
164 pretending it was allocated at the previous nesting level.
166 Automatic variables are also assigned temporary slots, at the nesting
167 level where they are defined. They are marked a "kept" so that
168 free_temp_slots will not free them. */
170 struct temp_slot GTY(())
172 /* Points to next temporary slot. */
173 struct temp_slot *next;
174 /* The rtx to used to reference the slot. */
176 /* The rtx used to represent the address if not the address of the
177 slot above. May be an EXPR_LIST if multiple addresses exist. */
179 /* The alignment (in bits) of the slot. */
181 /* The size, in units, of the slot. */
183 /* The type of the object in the slot, or zero if it doesn't correspond
184 to a type. We use this to determine whether a slot can be reused.
185 It can be reused if objects of the type of the new slot will always
186 conflict with objects of the type of the old slot. */
188 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
190 /* Nonzero if this temporary is currently in use. */
192 /* Nonzero if this temporary has its address taken. */
194 /* Nesting level at which this slot is being used. */
196 /* Nonzero if this should survive a call to free_temp_slots. */
198 /* The offset of the slot from the frame_pointer, including extra space
199 for alignment. This info is for combine_temp_slots. */
200 HOST_WIDE_INT base_offset;
201 /* The size of the slot, including extra space for alignment. This
202 info is for combine_temp_slots. */
203 HOST_WIDE_INT full_size;
206 /* This structure is used to record MEMs or pseudos used to replace VAR, any
207 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
208 maintain this list in case two operands of an insn were required to match;
209 in that case we must ensure we use the same replacement. */
211 struct fixup_replacement GTY(())
215 struct fixup_replacement *next;
218 struct insns_for_mem_entry
222 /* These are the INSNs which reference the MEM. */
226 /* Forward declarations. */
228 static rtx assign_stack_local_1 PARAMS ((enum machine_mode, HOST_WIDE_INT,
229 int, struct function *));
230 static struct temp_slot *find_temp_slot_from_address PARAMS ((rtx));
231 static void put_reg_into_stack PARAMS ((struct function *, rtx, tree,
232 enum machine_mode, enum machine_mode,
233 int, unsigned int, int,
235 static void schedule_fixup_var_refs PARAMS ((struct function *, rtx, tree,
238 static void fixup_var_refs PARAMS ((rtx, enum machine_mode, int, rtx,
240 static struct fixup_replacement
241 *find_fixup_replacement PARAMS ((struct fixup_replacement **, rtx));
242 static void fixup_var_refs_insns PARAMS ((rtx, rtx, enum machine_mode,
244 static void fixup_var_refs_insns_with_hash
245 PARAMS ((htab_t, rtx,
246 enum machine_mode, int, rtx));
247 static void fixup_var_refs_insn PARAMS ((rtx, rtx, enum machine_mode,
249 static void fixup_var_refs_1 PARAMS ((rtx, enum machine_mode, rtx *, rtx,
250 struct fixup_replacement **, rtx));
251 static rtx fixup_memory_subreg PARAMS ((rtx, rtx, enum machine_mode, int));
252 static rtx walk_fixup_memory_subreg PARAMS ((rtx, rtx, enum machine_mode,
254 static rtx fixup_stack_1 PARAMS ((rtx, rtx));
255 static void optimize_bit_field PARAMS ((rtx, rtx, rtx *));
256 static void instantiate_decls PARAMS ((tree, int));
257 static void instantiate_decls_1 PARAMS ((tree, int));
258 static void instantiate_decl PARAMS ((rtx, HOST_WIDE_INT, int));
259 static rtx instantiate_new_reg PARAMS ((rtx, HOST_WIDE_INT *));
260 static int instantiate_virtual_regs_1 PARAMS ((rtx *, rtx, int));
261 static void delete_handlers PARAMS ((void));
262 static void pad_to_arg_alignment PARAMS ((struct args_size *, int,
263 struct args_size *));
264 static void pad_below PARAMS ((struct args_size *, enum machine_mode,
266 static rtx round_trampoline_addr PARAMS ((rtx));
267 static rtx adjust_trampoline_addr PARAMS ((rtx));
268 static tree *identify_blocks_1 PARAMS ((rtx, tree *, tree *, tree *));
269 static void reorder_blocks_0 PARAMS ((tree));
270 static void reorder_blocks_1 PARAMS ((rtx, tree, varray_type *));
271 static void reorder_fix_fragments PARAMS ((tree));
272 static tree blocks_nreverse PARAMS ((tree));
273 static int all_blocks PARAMS ((tree, tree *));
274 static tree *get_block_vector PARAMS ((tree, int *));
275 extern tree debug_find_var_in_block_tree PARAMS ((tree, tree));
276 /* We always define `record_insns' even if its not used so that we
277 can always export `prologue_epilogue_contains'. */
278 static void record_insns PARAMS ((rtx, varray_type *)) ATTRIBUTE_UNUSED;
279 static int contains PARAMS ((rtx, varray_type));
281 static void emit_return_into_block PARAMS ((basic_block, rtx));
283 static void put_addressof_into_stack PARAMS ((rtx, htab_t));
284 static bool purge_addressof_1 PARAMS ((rtx *, rtx, int, int, int, htab_t));
285 static void purge_single_hard_subreg_set PARAMS ((rtx));
286 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
287 static rtx keep_stack_depressed PARAMS ((rtx));
289 static int is_addressof PARAMS ((rtx *, void *));
290 static hashval_t insns_for_mem_hash PARAMS ((const void *));
291 static int insns_for_mem_comp PARAMS ((const void *, const void *));
292 static int insns_for_mem_walk PARAMS ((rtx *, void *));
293 static void compute_insns_for_mem PARAMS ((rtx, rtx, htab_t));
294 static void prepare_function_start PARAMS ((void));
295 static void do_clobber_return_reg PARAMS ((rtx, void *));
296 static void do_use_return_reg PARAMS ((rtx, void *));
297 static void instantiate_virtual_regs_lossage PARAMS ((rtx));
299 /* Pointer to chain of `struct function' for containing functions. */
300 static GTY(()) struct function *outer_function_chain;
302 /* List of insns that were postponed by purge_addressof_1. */
303 static rtx postponed_insns;
305 /* Given a function decl for a containing function,
306 return the `struct function' for it. */
309 find_function_data (decl)
314 for (p = outer_function_chain; p; p = p->outer)
321 /* Save the current context for compilation of a nested function.
322 This is called from language-specific code. The caller should use
323 the enter_nested langhook to save any language-specific state,
324 since this function knows only about language-independent
328 push_function_context_to (context)
335 if (context == current_function_decl)
336 cfun->contains_functions = 1;
339 struct function *containing = find_function_data (context);
340 containing->contains_functions = 1;
345 init_dummy_function_start ();
348 p->outer = outer_function_chain;
349 outer_function_chain = p;
350 p->fixup_var_refs_queue = 0;
352 (*lang_hooks.function.enter_nested) (p);
358 push_function_context ()
360 push_function_context_to (current_function_decl);
363 /* Restore the last saved context, at the end of a nested function.
364 This function is called from language-specific code. */
367 pop_function_context_from (context)
368 tree context ATTRIBUTE_UNUSED;
370 struct function *p = outer_function_chain;
371 struct var_refs_queue *queue;
374 outer_function_chain = p->outer;
376 current_function_decl = p->decl;
379 restore_emit_status (p);
381 (*lang_hooks.function.leave_nested) (p);
383 /* Finish doing put_var_into_stack for any of our variables which became
384 addressable during the nested function. If only one entry has to be
385 fixed up, just do that one. Otherwise, first make a list of MEMs that
386 are not to be unshared. */
387 if (p->fixup_var_refs_queue == 0)
389 else if (p->fixup_var_refs_queue->next == 0)
390 fixup_var_refs (p->fixup_var_refs_queue->modified,
391 p->fixup_var_refs_queue->promoted_mode,
392 p->fixup_var_refs_queue->unsignedp,
393 p->fixup_var_refs_queue->modified, 0);
398 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
399 list = gen_rtx_EXPR_LIST (VOIDmode, queue->modified, list);
401 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
402 fixup_var_refs (queue->modified, queue->promoted_mode,
403 queue->unsignedp, list, 0);
407 p->fixup_var_refs_queue = 0;
409 /* Reset variables that have known state during rtx generation. */
410 rtx_equal_function_value_matters = 1;
411 virtuals_instantiated = 0;
412 generating_concat_p = 1;
416 pop_function_context ()
418 pop_function_context_from (current_function_decl);
421 /* Clear out all parts of the state in F that can safely be discarded
422 after the function has been parsed, but not compiled, to let
423 garbage collection reclaim the memory. */
426 free_after_parsing (f)
429 /* f->expr->forced_labels is used by code generation. */
430 /* f->emit->regno_reg_rtx is used by code generation. */
431 /* f->varasm is used by code generation. */
432 /* f->eh->eh_return_stub_label is used by code generation. */
434 (*lang_hooks.function.final) (f);
438 /* Clear out all parts of the state in F that can safely be discarded
439 after the function has been compiled, to let garbage collection
440 reclaim the memory. */
443 free_after_compilation (f)
452 f->x_temp_slots = NULL;
453 f->arg_offset_rtx = NULL;
454 f->return_rtx = NULL;
455 f->internal_arg_pointer = NULL;
456 f->x_nonlocal_labels = NULL;
457 f->x_nonlocal_goto_handler_slots = NULL;
458 f->x_nonlocal_goto_handler_labels = NULL;
459 f->x_nonlocal_goto_stack_level = NULL;
460 f->x_cleanup_label = NULL;
461 f->x_return_label = NULL;
462 f->computed_goto_common_label = NULL;
463 f->computed_goto_common_reg = NULL;
464 f->x_save_expr_regs = NULL;
465 f->x_stack_slot_list = NULL;
466 f->x_rtl_expr_chain = NULL;
467 f->x_tail_recursion_label = NULL;
468 f->x_tail_recursion_reentry = NULL;
469 f->x_arg_pointer_save_area = NULL;
470 f->x_clobber_return_insn = NULL;
471 f->x_context_display = NULL;
472 f->x_trampoline_list = NULL;
473 f->x_parm_birth_insn = NULL;
474 f->x_last_parm_insn = NULL;
475 f->x_parm_reg_stack_loc = NULL;
476 f->fixup_var_refs_queue = NULL;
477 f->original_arg_vector = NULL;
478 f->original_decl_initial = NULL;
479 f->inl_last_parm_insn = NULL;
480 f->epilogue_delay_list = NULL;
483 /* Allocate fixed slots in the stack frame of the current function. */
485 /* Return size needed for stack frame based on slots so far allocated in
487 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
488 the caller may have to do that. */
491 get_func_frame_size (f)
494 #ifdef FRAME_GROWS_DOWNWARD
495 return -f->x_frame_offset;
497 return f->x_frame_offset;
501 /* Return size needed for stack frame based on slots so far allocated.
502 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
503 the caller may have to do that. */
507 return get_func_frame_size (cfun);
510 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
511 with machine mode MODE.
513 ALIGN controls the amount of alignment for the address of the slot:
514 0 means according to MODE,
515 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
516 positive specifies alignment boundary in bits.
518 We do not round to stack_boundary here.
520 FUNCTION specifies the function to allocate in. */
523 assign_stack_local_1 (mode, size, align, function)
524 enum machine_mode mode;
527 struct function *function;
530 int bigend_correction = 0;
532 int frame_off, frame_alignment, frame_phase;
539 alignment = BIGGEST_ALIGNMENT;
541 alignment = GET_MODE_ALIGNMENT (mode);
543 /* Allow the target to (possibly) increase the alignment of this
545 type = (*lang_hooks.types.type_for_mode) (mode, 0);
547 alignment = LOCAL_ALIGNMENT (type, alignment);
549 alignment /= BITS_PER_UNIT;
551 else if (align == -1)
553 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
554 size = CEIL_ROUND (size, alignment);
557 alignment = align / BITS_PER_UNIT;
559 #ifdef FRAME_GROWS_DOWNWARD
560 function->x_frame_offset -= size;
563 /* Ignore alignment we can't do with expected alignment of the boundary. */
564 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
565 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
567 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
568 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
570 /* Calculate how many bytes the start of local variables is off from
572 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
573 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
574 frame_phase = frame_off ? frame_alignment - frame_off : 0;
576 /* Round the frame offset to the specified alignment. The default is
577 to always honor requests to align the stack but a port may choose to
578 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
579 if (STACK_ALIGNMENT_NEEDED
583 /* We must be careful here, since FRAME_OFFSET might be negative and
584 division with a negative dividend isn't as well defined as we might
585 like. So we instead assume that ALIGNMENT is a power of two and
586 use logical operations which are unambiguous. */
587 #ifdef FRAME_GROWS_DOWNWARD
588 function->x_frame_offset
589 = (FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment)
592 function->x_frame_offset
593 = (CEIL_ROUND (function->x_frame_offset - frame_phase, alignment)
598 /* On a big-endian machine, if we are allocating more space than we will use,
599 use the least significant bytes of those that are allocated. */
600 if (BYTES_BIG_ENDIAN && mode != BLKmode)
601 bigend_correction = size - GET_MODE_SIZE (mode);
603 /* If we have already instantiated virtual registers, return the actual
604 address relative to the frame pointer. */
605 if (function == cfun && virtuals_instantiated)
606 addr = plus_constant (frame_pointer_rtx,
608 (frame_offset + bigend_correction
609 + STARTING_FRAME_OFFSET, Pmode));
611 addr = plus_constant (virtual_stack_vars_rtx,
613 (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;
668 /* If SIZE is -1 it means that somebody tried to allocate a temporary
669 of a variable size. */
674 align = BIGGEST_ALIGNMENT;
676 align = GET_MODE_ALIGNMENT (mode);
679 type = (*lang_hooks.types.type_for_mode) (mode, 0);
682 align = LOCAL_ALIGNMENT (type, align);
684 /* Try to find an available, already-allocated temporary of the proper
685 mode which meets the size and alignment requirements. Choose the
686 smallest one with the closest alignment. */
687 for (p = temp_slots; p; p = p->next)
688 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
690 && objects_must_conflict_p (p->type, type)
691 && (best_p == 0 || best_p->size > p->size
692 || (best_p->size == p->size && best_p->align > p->align)))
694 if (p->align == align && p->size == size)
702 /* Make our best, if any, the one to use. */
705 /* If there are enough aligned bytes left over, make them into a new
706 temp_slot so that the extra bytes don't get wasted. Do this only
707 for BLKmode slots, so that we can be sure of the alignment. */
708 if (GET_MODE (best_p->slot) == BLKmode)
710 int alignment = best_p->align / BITS_PER_UNIT;
711 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
713 if (best_p->size - rounded_size >= alignment)
715 p = (struct temp_slot *) ggc_alloc (sizeof (struct temp_slot));
716 p->in_use = p->addr_taken = 0;
717 p->size = best_p->size - rounded_size;
718 p->base_offset = best_p->base_offset + rounded_size;
719 p->full_size = best_p->full_size - rounded_size;
720 p->slot = gen_rtx_MEM (BLKmode,
721 plus_constant (XEXP (best_p->slot, 0),
723 p->align = best_p->align;
726 p->type = best_p->type;
727 p->next = temp_slots;
730 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
733 best_p->size = rounded_size;
734 best_p->full_size = rounded_size;
741 /* If we still didn't find one, make a new temporary. */
744 HOST_WIDE_INT frame_offset_old = frame_offset;
746 p = (struct temp_slot *) ggc_alloc (sizeof (struct temp_slot));
748 /* We are passing an explicit alignment request to assign_stack_local.
749 One side effect of that is assign_stack_local will not round SIZE
750 to ensure the frame offset remains suitably aligned.
752 So for requests which depended on the rounding of SIZE, we go ahead
753 and round it now. We also make sure ALIGNMENT is at least
754 BIGGEST_ALIGNMENT. */
755 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
757 p->slot = assign_stack_local (mode,
759 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
765 /* The following slot size computation is necessary because we don't
766 know the actual size of the temporary slot until assign_stack_local
767 has performed all the frame alignment and size rounding for the
768 requested temporary. Note that extra space added for alignment
769 can be either above or below this stack slot depending on which
770 way the frame grows. We include the extra space if and only if it
771 is above this slot. */
772 #ifdef FRAME_GROWS_DOWNWARD
773 p->size = frame_offset_old - frame_offset;
778 /* Now define the fields used by combine_temp_slots. */
779 #ifdef FRAME_GROWS_DOWNWARD
780 p->base_offset = frame_offset;
781 p->full_size = frame_offset_old - frame_offset;
783 p->base_offset = frame_offset_old;
784 p->full_size = frame_offset - frame_offset_old;
787 p->next = temp_slots;
793 p->rtl_expr = seq_rtl_expr;
798 p->level = target_temp_slot_level;
803 p->level = var_temp_slot_level;
808 p->level = temp_slot_level;
813 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
814 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
815 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
817 /* If we know the alias set for the memory that will be used, use
818 it. If there's no TYPE, then we don't know anything about the
819 alias set for the memory. */
820 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
821 set_mem_align (slot, align);
823 /* If a type is specified, set the relevant flags. */
826 RTX_UNCHANGING_P (slot) = (lang_hooks.honor_readonly
827 && TYPE_READONLY (type));
828 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
829 MEM_SET_IN_STRUCT_P (slot, AGGREGATE_TYPE_P (type));
835 /* Allocate a temporary stack slot and record it for possible later
836 reuse. First three arguments are same as in preceding function. */
839 assign_stack_temp (mode, size, keep)
840 enum machine_mode mode;
844 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
847 /* Assign a temporary.
848 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
849 and so that should be used in error messages. In either case, we
850 allocate of the given type.
851 KEEP is as for assign_stack_temp.
852 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
853 it is 0 if a register is OK.
854 DONT_PROMOTE is 1 if we should not promote values in register
858 assign_temp (type_or_decl, keep, memory_required, dont_promote)
862 int dont_promote ATTRIBUTE_UNUSED;
865 enum machine_mode mode;
866 #ifndef PROMOTE_FOR_CALL_ONLY
870 if (DECL_P (type_or_decl))
871 decl = type_or_decl, type = TREE_TYPE (decl);
873 decl = NULL, type = type_or_decl;
875 mode = TYPE_MODE (type);
876 #ifndef PROMOTE_FOR_CALL_ONLY
877 unsignedp = TREE_UNSIGNED (type);
880 if (mode == BLKmode || memory_required)
882 HOST_WIDE_INT size = int_size_in_bytes (type);
885 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
886 problems with allocating the stack space. */
890 /* Unfortunately, we don't yet know how to allocate variable-sized
891 temporaries. However, sometimes we have a fixed upper limit on
892 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
893 instead. This is the case for Chill variable-sized strings. */
894 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
895 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
896 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
897 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
899 /* The size of the temporary may be too large to fit into an integer. */
900 /* ??? Not sure this should happen except for user silliness, so limit
901 this to things that aren't compiler-generated temporaries. The
902 rest of the time we'll abort in assign_stack_temp_for_type. */
903 if (decl && size == -1
904 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
906 error_with_decl (decl, "size of variable `%s' is too large");
910 tmp = assign_stack_temp_for_type (mode, size, keep, type);
914 #ifndef PROMOTE_FOR_CALL_ONLY
916 mode = promote_mode (type, mode, &unsignedp, 0);
919 return gen_reg_rtx (mode);
922 /* Combine temporary stack slots which are adjacent on the stack.
924 This allows for better use of already allocated stack space. This is only
925 done for BLKmode slots because we can be sure that we won't have alignment
926 problems in this case. */
929 combine_temp_slots ()
931 struct temp_slot *p, *q;
932 struct temp_slot *prev_p, *prev_q;
935 /* We can't combine slots, because the information about which slot
936 is in which alias set will be lost. */
937 if (flag_strict_aliasing)
940 /* If there are a lot of temp slots, don't do anything unless
941 high levels of optimization. */
942 if (! flag_expensive_optimizations)
943 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
944 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
947 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
951 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
952 for (q = p->next, prev_q = p; q; q = prev_q->next)
955 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
957 if (p->base_offset + p->full_size == q->base_offset)
959 /* Q comes after P; combine Q into P. */
961 p->full_size += q->full_size;
964 else if (q->base_offset + q->full_size == p->base_offset)
966 /* P comes after Q; combine P into Q. */
968 q->full_size += p->full_size;
973 /* Either delete Q or advance past it. */
975 prev_q->next = q->next;
979 /* Either delete P or advance past it. */
983 prev_p->next = p->next;
985 temp_slots = p->next;
992 /* Find the temp slot corresponding to the object at address X. */
994 static struct temp_slot *
995 find_temp_slot_from_address (x)
1001 for (p = temp_slots; p; p = p->next)
1006 else if (XEXP (p->slot, 0) == x
1008 || (GET_CODE (x) == PLUS
1009 && XEXP (x, 0) == virtual_stack_vars_rtx
1010 && GET_CODE (XEXP (x, 1)) == CONST_INT
1011 && INTVAL (XEXP (x, 1)) >= p->base_offset
1012 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
1015 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
1016 for (next = p->address; next; next = XEXP (next, 1))
1017 if (XEXP (next, 0) == x)
1021 /* If we have a sum involving a register, see if it points to a temp
1023 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
1024 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
1026 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
1027 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1033 /* Indicate that NEW is an alternate way of referring to the temp slot
1034 that previously was known by OLD. */
1037 update_temp_slot_address (old, new)
1040 struct temp_slot *p;
1042 if (rtx_equal_p (old, new))
1045 p = find_temp_slot_from_address (old);
1047 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1048 is a register, see if one operand of the PLUS is a temporary
1049 location. If so, NEW points into it. Otherwise, if both OLD and
1050 NEW are a PLUS and if there is a register in common between them.
1051 If so, try a recursive call on those values. */
1054 if (GET_CODE (old) != PLUS)
1057 if (GET_CODE (new) == REG)
1059 update_temp_slot_address (XEXP (old, 0), new);
1060 update_temp_slot_address (XEXP (old, 1), new);
1063 else if (GET_CODE (new) != PLUS)
1066 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1067 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1068 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1069 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1070 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1071 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1072 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1073 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1078 /* Otherwise add an alias for the temp's address. */
1079 else if (p->address == 0)
1083 if (GET_CODE (p->address) != EXPR_LIST)
1084 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1086 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1090 /* If X could be a reference to a temporary slot, mark the fact that its
1091 address was taken. */
1094 mark_temp_addr_taken (x)
1097 struct temp_slot *p;
1102 /* If X is not in memory or is at a constant address, it cannot be in
1103 a temporary slot. */
1104 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1107 p = find_temp_slot_from_address (XEXP (x, 0));
1112 /* If X could be a reference to a temporary slot, mark that slot as
1113 belonging to the to one level higher than the current level. If X
1114 matched one of our slots, just mark that one. Otherwise, we can't
1115 easily predict which it is, so upgrade all of them. Kept slots
1116 need not be touched.
1118 This is called when an ({...}) construct occurs and a statement
1119 returns a value in memory. */
1122 preserve_temp_slots (x)
1125 struct temp_slot *p = 0;
1127 /* If there is no result, we still might have some objects whose address
1128 were taken, so we need to make sure they stay around. */
1131 for (p = temp_slots; p; p = p->next)
1132 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1138 /* If X is a register that is being used as a pointer, see if we have
1139 a temporary slot we know it points to. To be consistent with
1140 the code below, we really should preserve all non-kept slots
1141 if we can't find a match, but that seems to be much too costly. */
1142 if (GET_CODE (x) == REG && REG_POINTER (x))
1143 p = find_temp_slot_from_address (x);
1145 /* If X is not in memory or is at a constant address, it cannot be in
1146 a temporary slot, but it can contain something whose address was
1148 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1150 for (p = temp_slots; p; p = p->next)
1151 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1157 /* First see if we can find a match. */
1159 p = find_temp_slot_from_address (XEXP (x, 0));
1163 /* Move everything at our level whose address was taken to our new
1164 level in case we used its address. */
1165 struct temp_slot *q;
1167 if (p->level == temp_slot_level)
1169 for (q = temp_slots; q; q = q->next)
1170 if (q != p && q->addr_taken && q->level == p->level)
1179 /* Otherwise, preserve all non-kept slots at this level. */
1180 for (p = temp_slots; p; p = p->next)
1181 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1185 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1186 with that RTL_EXPR, promote it into a temporary slot at the present
1187 level so it will not be freed when we free slots made in the
1191 preserve_rtl_expr_result (x)
1194 struct temp_slot *p;
1196 /* If X is not in memory or is at a constant address, it cannot be in
1197 a temporary slot. */
1198 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1201 /* If we can find a match, move it to our level unless it is already at
1203 p = find_temp_slot_from_address (XEXP (x, 0));
1206 p->level = MIN (p->level, temp_slot_level);
1213 /* Free all temporaries used so far. This is normally called at the end
1214 of generating code for a statement. Don't free any temporaries
1215 currently in use for an RTL_EXPR that hasn't yet been emitted.
1216 We could eventually do better than this since it can be reused while
1217 generating the same RTL_EXPR, but this is complex and probably not
1223 struct temp_slot *p;
1225 for (p = temp_slots; p; p = p->next)
1226 if (p->in_use && p->level == temp_slot_level && ! p->keep
1227 && p->rtl_expr == 0)
1230 combine_temp_slots ();
1233 /* Free all temporary slots used in T, an RTL_EXPR node. */
1236 free_temps_for_rtl_expr (t)
1239 struct temp_slot *p;
1241 for (p = temp_slots; p; p = p->next)
1242 if (p->rtl_expr == t)
1244 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1245 needs to be preserved. This can happen if a temporary in
1246 the RTL_EXPR was addressed; preserve_temp_slots will move
1247 the temporary into a higher level. */
1248 if (temp_slot_level <= p->level)
1251 p->rtl_expr = NULL_TREE;
1254 combine_temp_slots ();
1257 /* Mark all temporaries ever allocated in this function as not suitable
1258 for reuse until the current level is exited. */
1261 mark_all_temps_used ()
1263 struct temp_slot *p;
1265 for (p = temp_slots; p; p = p->next)
1267 p->in_use = p->keep = 1;
1268 p->level = MIN (p->level, temp_slot_level);
1272 /* Push deeper into the nesting level for stack temporaries. */
1280 /* Pop a temporary nesting level. All slots in use in the current level
1286 struct temp_slot *p;
1288 for (p = temp_slots; p; p = p->next)
1289 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1292 combine_temp_slots ();
1297 /* Initialize temporary slots. */
1302 /* We have not allocated any temporaries yet. */
1304 temp_slot_level = 0;
1305 var_temp_slot_level = 0;
1306 target_temp_slot_level = 0;
1309 /* Retroactively move an auto variable from a register to a stack
1310 slot. This is done when an address-reference to the variable is
1311 seen. If RESCAN is true, all previously emitted instructions are
1312 examined and modified to handle the fact that DECL is now
1316 put_var_into_stack (decl, rescan)
1321 enum machine_mode promoted_mode, decl_mode;
1322 struct function *function = 0;
1324 int can_use_addressof;
1325 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1326 int usedp = (TREE_USED (decl)
1327 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1329 context = decl_function_context (decl);
1331 /* Get the current rtl used for this object and its original mode. */
1332 reg = (TREE_CODE (decl) == SAVE_EXPR
1333 ? SAVE_EXPR_RTL (decl)
1334 : DECL_RTL_IF_SET (decl));
1336 /* No need to do anything if decl has no rtx yet
1337 since in that case caller is setting TREE_ADDRESSABLE
1338 and a stack slot will be assigned when the rtl is made. */
1342 /* Get the declared mode for this object. */
1343 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1344 : DECL_MODE (decl));
1345 /* Get the mode it's actually stored in. */
1346 promoted_mode = GET_MODE (reg);
1348 /* If this variable comes from an outer function, find that
1349 function's saved context. Don't use find_function_data here,
1350 because it might not be in any active function.
1351 FIXME: Is that really supposed to happen?
1352 It does in ObjC at least. */
1353 if (context != current_function_decl && context != inline_function_decl)
1354 for (function = outer_function_chain; function; function = function->outer)
1355 if (function->decl == context)
1358 /* If this is a variable-size object with a pseudo to address it,
1359 put that pseudo into the stack, if the var is nonlocal. */
1360 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1361 && GET_CODE (reg) == MEM
1362 && GET_CODE (XEXP (reg, 0)) == REG
1363 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1365 reg = XEXP (reg, 0);
1366 decl_mode = promoted_mode = GET_MODE (reg);
1372 /* FIXME make it work for promoted modes too */
1373 && decl_mode == promoted_mode
1374 #ifdef NON_SAVING_SETJMP
1375 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1379 /* If we can't use ADDRESSOF, make sure we see through one we already
1381 if (! can_use_addressof && GET_CODE (reg) == MEM
1382 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1383 reg = XEXP (XEXP (reg, 0), 0);
1385 /* Now we should have a value that resides in one or more pseudo regs. */
1387 if (GET_CODE (reg) == REG)
1389 /* If this variable lives in the current function and we don't need
1390 to put things in the stack for the sake of setjmp, try to keep it
1391 in a register until we know we actually need the address. */
1392 if (can_use_addressof)
1393 gen_mem_addressof (reg, decl, rescan);
1395 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1396 decl_mode, volatilep, 0, usedp, 0);
1398 else if (GET_CODE (reg) == CONCAT)
1400 /* A CONCAT contains two pseudos; put them both in the stack.
1401 We do it so they end up consecutive.
1402 We fixup references to the parts only after we fixup references
1403 to the whole CONCAT, lest we do double fixups for the latter
1405 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1406 tree part_type = (*lang_hooks.types.type_for_mode) (part_mode, 0);
1407 rtx lopart = XEXP (reg, 0);
1408 rtx hipart = XEXP (reg, 1);
1409 #ifdef FRAME_GROWS_DOWNWARD
1410 /* Since part 0 should have a lower address, do it second. */
1411 put_reg_into_stack (function, hipart, part_type, part_mode,
1412 part_mode, volatilep, 0, 0, 0);
1413 put_reg_into_stack (function, lopart, part_type, part_mode,
1414 part_mode, volatilep, 0, 0, 0);
1416 put_reg_into_stack (function, lopart, part_type, part_mode,
1417 part_mode, volatilep, 0, 0, 0);
1418 put_reg_into_stack (function, hipart, part_type, part_mode,
1419 part_mode, volatilep, 0, 0, 0);
1422 /* Change the CONCAT into a combined MEM for both parts. */
1423 PUT_CODE (reg, MEM);
1424 MEM_ATTRS (reg) = 0;
1426 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1427 already computed alias sets. Here we want to re-generate. */
1429 SET_DECL_RTL (decl, NULL);
1430 set_mem_attributes (reg, decl, 1);
1432 SET_DECL_RTL (decl, reg);
1434 /* The two parts are in memory order already.
1435 Use the lower parts address as ours. */
1436 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1437 /* Prevent sharing of rtl that might lose. */
1438 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1439 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1440 if (usedp && rescan)
1442 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1444 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1445 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1452 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1453 into the stack frame of FUNCTION (0 means the current function).
1454 DECL_MODE is the machine mode of the user-level data type.
1455 PROMOTED_MODE is the machine mode of the register.
1456 VOLATILE_P is nonzero if this is for a "volatile" decl.
1457 USED_P is nonzero if this reg might have already been used in an insn. */
1460 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1461 original_regno, used_p, ht)
1462 struct function *function;
1465 enum machine_mode promoted_mode, decl_mode;
1467 unsigned int original_regno;
1471 struct function *func = function ? function : cfun;
1473 unsigned int regno = original_regno;
1476 regno = REGNO (reg);
1478 if (regno < func->x_max_parm_reg)
1479 new = func->x_parm_reg_stack_loc[regno];
1482 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1484 PUT_CODE (reg, MEM);
1485 PUT_MODE (reg, decl_mode);
1486 XEXP (reg, 0) = XEXP (new, 0);
1487 MEM_ATTRS (reg) = 0;
1488 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1489 MEM_VOLATILE_P (reg) = volatile_p;
1491 /* If this is a memory ref that contains aggregate components,
1492 mark it as such for cse and loop optimize. If we are reusing a
1493 previously generated stack slot, then we need to copy the bit in
1494 case it was set for other reasons. For instance, it is set for
1495 __builtin_va_alist. */
1498 MEM_SET_IN_STRUCT_P (reg,
1499 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1500 set_mem_alias_set (reg, get_alias_set (type));
1504 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1507 /* Make sure that all refs to the variable, previously made
1508 when it was a register, are fixed up to be valid again.
1509 See function above for meaning of arguments. */
1512 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht)
1513 struct function *function;
1516 enum machine_mode promoted_mode;
1519 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1523 struct var_refs_queue *temp;
1526 = (struct var_refs_queue *) ggc_alloc (sizeof (struct var_refs_queue));
1527 temp->modified = reg;
1528 temp->promoted_mode = promoted_mode;
1529 temp->unsignedp = unsigned_p;
1530 temp->next = function->fixup_var_refs_queue;
1531 function->fixup_var_refs_queue = temp;
1534 /* Variable is local; fix it up now. */
1535 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht);
1539 fixup_var_refs (var, promoted_mode, unsignedp, may_share, ht)
1541 enum machine_mode promoted_mode;
1547 rtx first_insn = get_insns ();
1548 struct sequence_stack *stack = seq_stack;
1549 tree rtl_exps = rtl_expr_chain;
1551 /* If there's a hash table, it must record all uses of VAR. */
1556 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp,
1561 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1562 stack == 0, may_share);
1564 /* Scan all pending sequences too. */
1565 for (; stack; stack = stack->next)
1567 push_to_full_sequence (stack->first, stack->last);
1568 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1569 stack->next != 0, may_share);
1570 /* Update remembered end of sequence
1571 in case we added an insn at the end. */
1572 stack->last = get_last_insn ();
1576 /* Scan all waiting RTL_EXPRs too. */
1577 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1579 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1580 if (seq != const0_rtx && seq != 0)
1582 push_to_sequence (seq);
1583 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1590 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1591 some part of an insn. Return a struct fixup_replacement whose OLD
1592 value is equal to X. Allocate a new structure if no such entry exists. */
1594 static struct fixup_replacement *
1595 find_fixup_replacement (replacements, x)
1596 struct fixup_replacement **replacements;
1599 struct fixup_replacement *p;
1601 /* See if we have already replaced this. */
1602 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1607 p = (struct fixup_replacement *) xmalloc (sizeof (struct fixup_replacement));
1610 p->next = *replacements;
1617 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1618 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1619 for the current function. MAY_SHARE is either a MEM that is not
1620 to be unshared or a list of them. */
1623 fixup_var_refs_insns (insn, var, promoted_mode, unsignedp, toplevel, may_share)
1626 enum machine_mode promoted_mode;
1633 /* fixup_var_refs_insn might modify insn, so save its next
1635 rtx next = NEXT_INSN (insn);
1637 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1638 the three sequences they (potentially) contain, and process
1639 them recursively. The CALL_INSN itself is not interesting. */
1641 if (GET_CODE (insn) == CALL_INSN
1642 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1646 /* Look at the Normal call, sibling call and tail recursion
1647 sequences attached to the CALL_PLACEHOLDER. */
1648 for (i = 0; i < 3; i++)
1650 rtx seq = XEXP (PATTERN (insn), i);
1653 push_to_sequence (seq);
1654 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1656 XEXP (PATTERN (insn), i) = get_insns ();
1662 else if (INSN_P (insn))
1663 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel,
1670 /* Look up the insns which reference VAR in HT and fix them up. Other
1671 arguments are the same as fixup_var_refs_insns.
1673 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1674 because the hash table will point straight to the interesting insn
1675 (inside the CALL_PLACEHOLDER). */
1678 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp, may_share)
1681 enum machine_mode promoted_mode;
1685 struct insns_for_mem_entry tmp;
1686 struct insns_for_mem_entry *ime;
1690 ime = (struct insns_for_mem_entry *) htab_find (ht, &tmp);
1691 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1))
1692 if (INSN_P (XEXP (insn_list, 0)))
1693 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode,
1694 unsignedp, 1, may_share);
1698 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1699 the insn under examination, VAR is the variable to fix up
1700 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1701 TOPLEVEL is nonzero if this is the main insn chain for this
1705 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel, no_share)
1708 enum machine_mode promoted_mode;
1714 rtx set, prev, prev_set;
1717 /* Remember the notes in case we delete the insn. */
1718 note = REG_NOTES (insn);
1720 /* If this is a CLOBBER of VAR, delete it.
1722 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1723 and REG_RETVAL notes too. */
1724 if (GET_CODE (PATTERN (insn)) == CLOBBER
1725 && (XEXP (PATTERN (insn), 0) == var
1726 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1727 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1728 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1730 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1731 /* The REG_LIBCALL note will go away since we are going to
1732 turn INSN into a NOTE, so just delete the
1733 corresponding REG_RETVAL note. */
1734 remove_note (XEXP (note, 0),
1735 find_reg_note (XEXP (note, 0), REG_RETVAL,
1741 /* The insn to load VAR from a home in the arglist
1742 is now a no-op. When we see it, just delete it.
1743 Similarly if this is storing VAR from a register from which
1744 it was loaded in the previous insn. This will occur
1745 when an ADDRESSOF was made for an arglist slot. */
1747 && (set = single_set (insn)) != 0
1748 && SET_DEST (set) == var
1749 /* If this represents the result of an insn group,
1750 don't delete the insn. */
1751 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1752 && (rtx_equal_p (SET_SRC (set), var)
1753 || (GET_CODE (SET_SRC (set)) == REG
1754 && (prev = prev_nonnote_insn (insn)) != 0
1755 && (prev_set = single_set (prev)) != 0
1756 && SET_DEST (prev_set) == SET_SRC (set)
1757 && rtx_equal_p (SET_SRC (prev_set), var))))
1763 struct fixup_replacement *replacements = 0;
1764 rtx next_insn = NEXT_INSN (insn);
1766 if (SMALL_REGISTER_CLASSES)
1768 /* If the insn that copies the results of a CALL_INSN
1769 into a pseudo now references VAR, we have to use an
1770 intermediate pseudo since we want the life of the
1771 return value register to be only a single insn.
1773 If we don't use an intermediate pseudo, such things as
1774 address computations to make the address of VAR valid
1775 if it is not can be placed between the CALL_INSN and INSN.
1777 To make sure this doesn't happen, we record the destination
1778 of the CALL_INSN and see if the next insn uses both that
1781 if (call_dest != 0 && GET_CODE (insn) == INSN
1782 && reg_mentioned_p (var, PATTERN (insn))
1783 && reg_mentioned_p (call_dest, PATTERN (insn)))
1785 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1787 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1789 PATTERN (insn) = replace_rtx (PATTERN (insn),
1793 if (GET_CODE (insn) == CALL_INSN
1794 && GET_CODE (PATTERN (insn)) == SET)
1795 call_dest = SET_DEST (PATTERN (insn));
1796 else if (GET_CODE (insn) == CALL_INSN
1797 && GET_CODE (PATTERN (insn)) == PARALLEL
1798 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1799 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1804 /* See if we have to do anything to INSN now that VAR is in
1805 memory. If it needs to be loaded into a pseudo, use a single
1806 pseudo for the entire insn in case there is a MATCH_DUP
1807 between two operands. We pass a pointer to the head of
1808 a list of struct fixup_replacements. If fixup_var_refs_1
1809 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1810 it will record them in this list.
1812 If it allocated a pseudo for any replacement, we copy into
1815 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1816 &replacements, no_share);
1818 /* If this is last_parm_insn, and any instructions were output
1819 after it to fix it up, then we must set last_parm_insn to
1820 the last such instruction emitted. */
1821 if (insn == last_parm_insn)
1822 last_parm_insn = PREV_INSN (next_insn);
1824 while (replacements)
1826 struct fixup_replacement *next;
1828 if (GET_CODE (replacements->new) == REG)
1833 /* OLD might be a (subreg (mem)). */
1834 if (GET_CODE (replacements->old) == SUBREG)
1836 = fixup_memory_subreg (replacements->old, insn,
1840 = fixup_stack_1 (replacements->old, insn);
1842 insert_before = insn;
1844 /* If we are changing the mode, do a conversion.
1845 This might be wasteful, but combine.c will
1846 eliminate much of the waste. */
1848 if (GET_MODE (replacements->new)
1849 != GET_MODE (replacements->old))
1852 convert_move (replacements->new,
1853 replacements->old, unsignedp);
1858 seq = gen_move_insn (replacements->new,
1861 emit_insn_before (seq, insert_before);
1864 next = replacements->next;
1865 free (replacements);
1866 replacements = next;
1870 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1871 But don't touch other insns referred to by reg-notes;
1872 we will get them elsewhere. */
1875 if (GET_CODE (note) != INSN_LIST)
1877 = walk_fixup_memory_subreg (XEXP (note, 0), insn,
1879 note = XEXP (note, 1);
1883 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1884 See if the rtx expression at *LOC in INSN needs to be changed.
1886 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1887 contain a list of original rtx's and replacements. If we find that we need
1888 to modify this insn by replacing a memory reference with a pseudo or by
1889 making a new MEM to implement a SUBREG, we consult that list to see if
1890 we have already chosen a replacement. If none has already been allocated,
1891 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1892 or the SUBREG, as appropriate, to the pseudo. */
1895 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements, no_share)
1897 enum machine_mode promoted_mode;
1900 struct fixup_replacement **replacements;
1905 RTX_CODE code = GET_CODE (x);
1908 struct fixup_replacement *replacement;
1913 if (XEXP (x, 0) == var)
1915 /* Prevent sharing of rtl that might lose. */
1916 rtx sub = copy_rtx (XEXP (var, 0));
1918 if (! validate_change (insn, loc, sub, 0))
1920 rtx y = gen_reg_rtx (GET_MODE (sub));
1923 /* We should be able to replace with a register or all is lost.
1924 Note that we can't use validate_change to verify this, since
1925 we're not caring for replacing all dups simultaneously. */
1926 if (! validate_replace_rtx (*loc, y, insn))
1929 /* Careful! First try to recognize a direct move of the
1930 value, mimicking how things are done in gen_reload wrt
1931 PLUS. Consider what happens when insn is a conditional
1932 move instruction and addsi3 clobbers flags. */
1935 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1939 if (recog_memoized (new_insn) < 0)
1941 /* That failed. Fall back on force_operand and hope. */
1944 sub = force_operand (sub, y);
1946 emit_insn (gen_move_insn (y, sub));
1952 /* Don't separate setter from user. */
1953 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1954 insn = PREV_INSN (insn);
1957 emit_insn_before (seq, insn);
1965 /* If we already have a replacement, use it. Otherwise,
1966 try to fix up this address in case it is invalid. */
1968 replacement = find_fixup_replacement (replacements, var);
1969 if (replacement->new)
1971 *loc = replacement->new;
1975 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1977 /* Unless we are forcing memory to register or we changed the mode,
1978 we can leave things the way they are if the insn is valid. */
1980 INSN_CODE (insn) = -1;
1981 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1982 && recog_memoized (insn) >= 0)
1985 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1989 /* If X contains VAR, we need to unshare it here so that we update
1990 each occurrence separately. But all identical MEMs in one insn
1991 must be replaced with the same rtx because of the possibility of
1994 if (reg_mentioned_p (var, x))
1996 replacement = find_fixup_replacement (replacements, x);
1997 if (replacement->new == 0)
1998 replacement->new = copy_most_rtx (x, no_share);
2000 *loc = x = replacement->new;
2001 code = GET_CODE (x);
2018 /* Note that in some cases those types of expressions are altered
2019 by optimize_bit_field, and do not survive to get here. */
2020 if (XEXP (x, 0) == var
2021 || (GET_CODE (XEXP (x, 0)) == SUBREG
2022 && SUBREG_REG (XEXP (x, 0)) == var))
2024 /* Get TEM as a valid MEM in the mode presently in the insn.
2026 We don't worry about the possibility of MATCH_DUP here; it
2027 is highly unlikely and would be tricky to handle. */
2030 if (GET_CODE (tem) == SUBREG)
2032 if (GET_MODE_BITSIZE (GET_MODE (tem))
2033 > GET_MODE_BITSIZE (GET_MODE (var)))
2035 replacement = find_fixup_replacement (replacements, var);
2036 if (replacement->new == 0)
2037 replacement->new = gen_reg_rtx (GET_MODE (var));
2038 SUBREG_REG (tem) = replacement->new;
2040 /* The following code works only if we have a MEM, so we
2041 need to handle the subreg here. We directly substitute
2042 it assuming that a subreg must be OK here. We already
2043 scheduled a replacement to copy the mem into the
2049 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2052 tem = fixup_stack_1 (tem, insn);
2054 /* Unless we want to load from memory, get TEM into the proper mode
2055 for an extract from memory. This can only be done if the
2056 extract is at a constant position and length. */
2058 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2059 && GET_CODE (XEXP (x, 2)) == CONST_INT
2060 && ! mode_dependent_address_p (XEXP (tem, 0))
2061 && ! MEM_VOLATILE_P (tem))
2063 enum machine_mode wanted_mode = VOIDmode;
2064 enum machine_mode is_mode = GET_MODE (tem);
2065 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2067 if (GET_CODE (x) == ZERO_EXTRACT)
2069 enum machine_mode new_mode
2070 = mode_for_extraction (EP_extzv, 1);
2071 if (new_mode != MAX_MACHINE_MODE)
2072 wanted_mode = new_mode;
2074 else if (GET_CODE (x) == SIGN_EXTRACT)
2076 enum machine_mode new_mode
2077 = mode_for_extraction (EP_extv, 1);
2078 if (new_mode != MAX_MACHINE_MODE)
2079 wanted_mode = new_mode;
2082 /* If we have a narrower mode, we can do something. */
2083 if (wanted_mode != VOIDmode
2084 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2086 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2087 rtx old_pos = XEXP (x, 2);
2090 /* If the bytes and bits are counted differently, we
2091 must adjust the offset. */
2092 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2093 offset = (GET_MODE_SIZE (is_mode)
2094 - GET_MODE_SIZE (wanted_mode) - offset);
2096 pos %= GET_MODE_BITSIZE (wanted_mode);
2098 newmem = adjust_address_nv (tem, wanted_mode, offset);
2100 /* Make the change and see if the insn remains valid. */
2101 INSN_CODE (insn) = -1;
2102 XEXP (x, 0) = newmem;
2103 XEXP (x, 2) = GEN_INT (pos);
2105 if (recog_memoized (insn) >= 0)
2108 /* Otherwise, restore old position. XEXP (x, 0) will be
2110 XEXP (x, 2) = old_pos;
2114 /* If we get here, the bitfield extract insn can't accept a memory
2115 reference. Copy the input into a register. */
2117 tem1 = gen_reg_rtx (GET_MODE (tem));
2118 emit_insn_before (gen_move_insn (tem1, tem), insn);
2125 if (SUBREG_REG (x) == var)
2127 /* If this is a special SUBREG made because VAR was promoted
2128 from a wider mode, replace it with VAR and call ourself
2129 recursively, this time saying that the object previously
2130 had its current mode (by virtue of the SUBREG). */
2132 if (SUBREG_PROMOTED_VAR_P (x))
2135 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements,
2140 /* If this SUBREG makes VAR wider, it has become a paradoxical
2141 SUBREG with VAR in memory, but these aren't allowed at this
2142 stage of the compilation. So load VAR into a pseudo and take
2143 a SUBREG of that pseudo. */
2144 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2146 replacement = find_fixup_replacement (replacements, var);
2147 if (replacement->new == 0)
2148 replacement->new = gen_reg_rtx (promoted_mode);
2149 SUBREG_REG (x) = replacement->new;
2153 /* See if we have already found a replacement for this SUBREG.
2154 If so, use it. Otherwise, make a MEM and see if the insn
2155 is recognized. If not, or if we should force MEM into a register,
2156 make a pseudo for this SUBREG. */
2157 replacement = find_fixup_replacement (replacements, x);
2158 if (replacement->new)
2160 *loc = replacement->new;
2164 replacement->new = *loc = fixup_memory_subreg (x, insn,
2167 INSN_CODE (insn) = -1;
2168 if (! flag_force_mem && recog_memoized (insn) >= 0)
2171 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2177 /* First do special simplification of bit-field references. */
2178 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2179 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2180 optimize_bit_field (x, insn, 0);
2181 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2182 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2183 optimize_bit_field (x, insn, 0);
2185 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2186 into a register and then store it back out. */
2187 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2188 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2189 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2190 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2191 > GET_MODE_SIZE (GET_MODE (var))))
2193 replacement = find_fixup_replacement (replacements, var);
2194 if (replacement->new == 0)
2195 replacement->new = gen_reg_rtx (GET_MODE (var));
2197 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2198 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2201 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2202 insn into a pseudo and store the low part of the pseudo into VAR. */
2203 if (GET_CODE (SET_DEST (x)) == SUBREG
2204 && SUBREG_REG (SET_DEST (x)) == var
2205 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2206 > GET_MODE_SIZE (GET_MODE (var))))
2208 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2209 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2216 rtx dest = SET_DEST (x);
2217 rtx src = SET_SRC (x);
2218 rtx outerdest = dest;
2220 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2221 || GET_CODE (dest) == SIGN_EXTRACT
2222 || GET_CODE (dest) == ZERO_EXTRACT)
2223 dest = XEXP (dest, 0);
2225 if (GET_CODE (src) == SUBREG)
2226 src = SUBREG_REG (src);
2228 /* If VAR does not appear at the top level of the SET
2229 just scan the lower levels of the tree. */
2231 if (src != var && dest != var)
2234 /* We will need to rerecognize this insn. */
2235 INSN_CODE (insn) = -1;
2237 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var
2238 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE)
2240 /* Since this case will return, ensure we fixup all the
2242 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2243 insn, replacements, no_share);
2244 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2245 insn, replacements, no_share);
2246 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2247 insn, replacements, no_share);
2249 tem = XEXP (outerdest, 0);
2251 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2252 that may appear inside a ZERO_EXTRACT.
2253 This was legitimate when the MEM was a REG. */
2254 if (GET_CODE (tem) == SUBREG
2255 && SUBREG_REG (tem) == var)
2256 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2258 tem = fixup_stack_1 (tem, insn);
2260 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2261 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2262 && ! mode_dependent_address_p (XEXP (tem, 0))
2263 && ! MEM_VOLATILE_P (tem))
2265 enum machine_mode wanted_mode;
2266 enum machine_mode is_mode = GET_MODE (tem);
2267 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2269 wanted_mode = mode_for_extraction (EP_insv, 0);
2271 /* If we have a narrower mode, we can do something. */
2272 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2274 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2275 rtx old_pos = XEXP (outerdest, 2);
2278 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2279 offset = (GET_MODE_SIZE (is_mode)
2280 - GET_MODE_SIZE (wanted_mode) - offset);
2282 pos %= GET_MODE_BITSIZE (wanted_mode);
2284 newmem = adjust_address_nv (tem, wanted_mode, offset);
2286 /* Make the change and see if the insn remains valid. */
2287 INSN_CODE (insn) = -1;
2288 XEXP (outerdest, 0) = newmem;
2289 XEXP (outerdest, 2) = GEN_INT (pos);
2291 if (recog_memoized (insn) >= 0)
2294 /* Otherwise, restore old position. XEXP (x, 0) will be
2296 XEXP (outerdest, 2) = old_pos;
2300 /* If we get here, the bit-field store doesn't allow memory
2301 or isn't located at a constant position. Load the value into
2302 a register, do the store, and put it back into memory. */
2304 tem1 = gen_reg_rtx (GET_MODE (tem));
2305 emit_insn_before (gen_move_insn (tem1, tem), insn);
2306 emit_insn_after (gen_move_insn (tem, tem1), insn);
2307 XEXP (outerdest, 0) = tem1;
2311 /* STRICT_LOW_PART is a no-op on memory references
2312 and it can cause combinations to be unrecognizable,
2315 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2316 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2318 /* A valid insn to copy VAR into or out of a register
2319 must be left alone, to avoid an infinite loop here.
2320 If the reference to VAR is by a subreg, fix that up,
2321 since SUBREG is not valid for a memref.
2322 Also fix up the address of the stack slot.
2324 Note that we must not try to recognize the insn until
2325 after we know that we have valid addresses and no
2326 (subreg (mem ...) ...) constructs, since these interfere
2327 with determining the validity of the insn. */
2329 if ((SET_SRC (x) == var
2330 || (GET_CODE (SET_SRC (x)) == SUBREG
2331 && SUBREG_REG (SET_SRC (x)) == var))
2332 && (GET_CODE (SET_DEST (x)) == REG
2333 || (GET_CODE (SET_DEST (x)) == SUBREG
2334 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2335 && GET_MODE (var) == promoted_mode
2336 && x == single_set (insn))
2340 if (GET_CODE (SET_SRC (x)) == SUBREG
2341 && (GET_MODE_SIZE (GET_MODE (SET_SRC (x)))
2342 > GET_MODE_SIZE (GET_MODE (var))))
2344 /* This (subreg VAR) is now a paradoxical subreg. We need
2345 to replace VAR instead of the subreg. */
2346 replacement = find_fixup_replacement (replacements, var);
2347 if (replacement->new == NULL_RTX)
2348 replacement->new = gen_reg_rtx (GET_MODE (var));
2349 SUBREG_REG (SET_SRC (x)) = replacement->new;
2353 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2354 if (replacement->new)
2355 SET_SRC (x) = replacement->new;
2356 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2357 SET_SRC (x) = replacement->new
2358 = fixup_memory_subreg (SET_SRC (x), insn, promoted_mode,
2361 SET_SRC (x) = replacement->new
2362 = fixup_stack_1 (SET_SRC (x), insn);
2365 if (recog_memoized (insn) >= 0)
2368 /* INSN is not valid, but we know that we want to
2369 copy SET_SRC (x) to SET_DEST (x) in some way. So
2370 we generate the move and see whether it requires more
2371 than one insn. If it does, we emit those insns and
2372 delete INSN. Otherwise, we can just replace the pattern
2373 of INSN; we have already verified above that INSN has
2374 no other function that to do X. */
2376 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2377 if (NEXT_INSN (pat) != NULL_RTX)
2379 last = emit_insn_before (pat, insn);
2381 /* INSN might have REG_RETVAL or other important notes, so
2382 we need to store the pattern of the last insn in the
2383 sequence into INSN similarly to the normal case. LAST
2384 should not have REG_NOTES, but we allow them if INSN has
2386 if (REG_NOTES (last) && REG_NOTES (insn))
2388 if (REG_NOTES (last))
2389 REG_NOTES (insn) = REG_NOTES (last);
2390 PATTERN (insn) = PATTERN (last);
2395 PATTERN (insn) = PATTERN (pat);
2400 if ((SET_DEST (x) == var
2401 || (GET_CODE (SET_DEST (x)) == SUBREG
2402 && SUBREG_REG (SET_DEST (x)) == var))
2403 && (GET_CODE (SET_SRC (x)) == REG
2404 || (GET_CODE (SET_SRC (x)) == SUBREG
2405 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2406 && GET_MODE (var) == promoted_mode
2407 && x == single_set (insn))
2411 if (GET_CODE (SET_DEST (x)) == SUBREG)
2412 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn,
2415 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2417 if (recog_memoized (insn) >= 0)
2420 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2421 if (NEXT_INSN (pat) != NULL_RTX)
2423 last = emit_insn_before (pat, insn);
2425 /* INSN might have REG_RETVAL or other important notes, so
2426 we need to store the pattern of the last insn in the
2427 sequence into INSN similarly to the normal case. LAST
2428 should not have REG_NOTES, but we allow them if INSN has
2430 if (REG_NOTES (last) && REG_NOTES (insn))
2432 if (REG_NOTES (last))
2433 REG_NOTES (insn) = REG_NOTES (last);
2434 PATTERN (insn) = PATTERN (last);
2439 PATTERN (insn) = PATTERN (pat);
2444 /* Otherwise, storing into VAR must be handled specially
2445 by storing into a temporary and copying that into VAR
2446 with a new insn after this one. Note that this case
2447 will be used when storing into a promoted scalar since
2448 the insn will now have different modes on the input
2449 and output and hence will be invalid (except for the case
2450 of setting it to a constant, which does not need any
2451 change if it is valid). We generate extra code in that case,
2452 but combine.c will eliminate it. */
2457 rtx fixeddest = SET_DEST (x);
2458 enum machine_mode temp_mode;
2460 /* STRICT_LOW_PART can be discarded, around a MEM. */
2461 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2462 fixeddest = XEXP (fixeddest, 0);
2463 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2464 if (GET_CODE (fixeddest) == SUBREG)
2466 fixeddest = fixup_memory_subreg (fixeddest, insn,
2468 temp_mode = GET_MODE (fixeddest);
2472 fixeddest = fixup_stack_1 (fixeddest, insn);
2473 temp_mode = promoted_mode;
2476 temp = gen_reg_rtx (temp_mode);
2478 emit_insn_after (gen_move_insn (fixeddest,
2479 gen_lowpart (GET_MODE (fixeddest),
2483 SET_DEST (x) = temp;
2491 /* Nothing special about this RTX; fix its operands. */
2493 fmt = GET_RTX_FORMAT (code);
2494 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2497 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements,
2499 else if (fmt[i] == 'E')
2502 for (j = 0; j < XVECLEN (x, i); j++)
2503 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2504 insn, replacements, no_share);
2509 /* Previously, X had the form (SUBREG:m1 (REG:PROMOTED_MODE ...)).
2510 The REG was placed on the stack, so X now has the form (SUBREG:m1
2513 Return an rtx (MEM:m1 newaddr) which is equivalent. If any insns
2514 must be emitted to compute NEWADDR, put them before INSN.
2516 UNCRITICAL nonzero means accept paradoxical subregs.
2517 This is used for subregs found inside REG_NOTES. */
2520 fixup_memory_subreg (x, insn, promoted_mode, uncritical)
2523 enum machine_mode promoted_mode;
2527 rtx mem = SUBREG_REG (x);
2528 rtx addr = XEXP (mem, 0);
2529 enum machine_mode mode = GET_MODE (x);
2532 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2533 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (mem)) && ! uncritical)
2536 offset = SUBREG_BYTE (x);
2537 if (BYTES_BIG_ENDIAN)
2538 /* If the PROMOTED_MODE is wider than the mode of the MEM, adjust
2539 the offset so that it points to the right location within the
2541 offset -= (GET_MODE_SIZE (promoted_mode) - GET_MODE_SIZE (GET_MODE (mem)));
2543 if (!flag_force_addr
2544 && memory_address_p (mode, plus_constant (addr, offset)))
2545 /* Shortcut if no insns need be emitted. */
2546 return adjust_address (mem, mode, offset);
2549 result = adjust_address (mem, mode, offset);
2553 emit_insn_before (seq, insn);
2557 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2558 Replace subexpressions of X in place.
2559 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2560 Otherwise return X, with its contents possibly altered.
2562 INSN, PROMOTED_MODE and UNCRITICAL are as for
2563 fixup_memory_subreg. */
2566 walk_fixup_memory_subreg (x, insn, promoted_mode, uncritical)
2569 enum machine_mode promoted_mode;
2579 code = GET_CODE (x);
2581 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2582 return fixup_memory_subreg (x, insn, promoted_mode, uncritical);
2584 /* Nothing special about this RTX; fix its operands. */
2586 fmt = GET_RTX_FORMAT (code);
2587 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2590 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn,
2591 promoted_mode, uncritical);
2592 else if (fmt[i] == 'E')
2595 for (j = 0; j < XVECLEN (x, i); j++)
2597 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn,
2598 promoted_mode, uncritical);
2604 /* For each memory ref within X, if it refers to a stack slot
2605 with an out of range displacement, put the address in a temp register
2606 (emitting new insns before INSN to load these registers)
2607 and alter the memory ref to use that register.
2608 Replace each such MEM rtx with a copy, to avoid clobberage. */
2611 fixup_stack_1 (x, insn)
2616 RTX_CODE code = GET_CODE (x);
2621 rtx ad = XEXP (x, 0);
2622 /* If we have address of a stack slot but it's not valid
2623 (displacement is too large), compute the sum in a register. */
2624 if (GET_CODE (ad) == PLUS
2625 && GET_CODE (XEXP (ad, 0)) == REG
2626 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2627 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2628 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2629 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2630 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2632 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2633 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2634 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2635 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2638 if (memory_address_p (GET_MODE (x), ad))
2642 temp = copy_to_reg (ad);
2645 emit_insn_before (seq, insn);
2646 return replace_equiv_address (x, temp);
2651 fmt = GET_RTX_FORMAT (code);
2652 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2655 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2656 else if (fmt[i] == 'E')
2659 for (j = 0; j < XVECLEN (x, i); j++)
2660 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2666 /* Optimization: a bit-field instruction whose field
2667 happens to be a byte or halfword in memory
2668 can be changed to a move instruction.
2670 We call here when INSN is an insn to examine or store into a bit-field.
2671 BODY is the SET-rtx to be altered.
2673 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2674 (Currently this is called only from function.c, and EQUIV_MEM
2678 optimize_bit_field (body, insn, equiv_mem)
2686 enum machine_mode mode;
2688 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2689 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2690 bitfield = SET_DEST (body), destflag = 1;
2692 bitfield = SET_SRC (body), destflag = 0;
2694 /* First check that the field being stored has constant size and position
2695 and is in fact a byte or halfword suitably aligned. */
2697 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2698 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2699 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2701 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2705 /* Now check that the containing word is memory, not a register,
2706 and that it is safe to change the machine mode. */
2708 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2709 memref = XEXP (bitfield, 0);
2710 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2712 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2713 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2714 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2715 memref = SUBREG_REG (XEXP (bitfield, 0));
2716 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2718 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2719 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2722 && ! mode_dependent_address_p (XEXP (memref, 0))
2723 && ! MEM_VOLATILE_P (memref))
2725 /* Now adjust the address, first for any subreg'ing
2726 that we are now getting rid of,
2727 and then for which byte of the word is wanted. */
2729 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2732 /* Adjust OFFSET to count bits from low-address byte. */
2733 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2734 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2735 - offset - INTVAL (XEXP (bitfield, 1)));
2737 /* Adjust OFFSET to count bytes from low-address byte. */
2738 offset /= BITS_PER_UNIT;
2739 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2741 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2742 / UNITS_PER_WORD) * UNITS_PER_WORD;
2743 if (BYTES_BIG_ENDIAN)
2744 offset -= (MIN (UNITS_PER_WORD,
2745 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2746 - MIN (UNITS_PER_WORD,
2747 GET_MODE_SIZE (GET_MODE (memref))));
2751 memref = adjust_address (memref, mode, offset);
2752 insns = get_insns ();
2754 emit_insn_before (insns, insn);
2756 /* Store this memory reference where
2757 we found the bit field reference. */
2761 validate_change (insn, &SET_DEST (body), memref, 1);
2762 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2764 rtx src = SET_SRC (body);
2765 while (GET_CODE (src) == SUBREG
2766 && SUBREG_BYTE (src) == 0)
2767 src = SUBREG_REG (src);
2768 if (GET_MODE (src) != GET_MODE (memref))
2769 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2770 validate_change (insn, &SET_SRC (body), src, 1);
2772 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2773 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2774 /* This shouldn't happen because anything that didn't have
2775 one of these modes should have got converted explicitly
2776 and then referenced through a subreg.
2777 This is so because the original bit-field was
2778 handled by agg_mode and so its tree structure had
2779 the same mode that memref now has. */
2784 rtx dest = SET_DEST (body);
2786 while (GET_CODE (dest) == SUBREG
2787 && SUBREG_BYTE (dest) == 0
2788 && (GET_MODE_CLASS (GET_MODE (dest))
2789 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2790 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2792 dest = SUBREG_REG (dest);
2794 validate_change (insn, &SET_DEST (body), dest, 1);
2796 if (GET_MODE (dest) == GET_MODE (memref))
2797 validate_change (insn, &SET_SRC (body), memref, 1);
2800 /* Convert the mem ref to the destination mode. */
2801 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2804 convert_move (newreg, memref,
2805 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2809 validate_change (insn, &SET_SRC (body), newreg, 1);
2813 /* See if we can convert this extraction or insertion into
2814 a simple move insn. We might not be able to do so if this
2815 was, for example, part of a PARALLEL.
2817 If we succeed, write out any needed conversions. If we fail,
2818 it is hard to guess why we failed, so don't do anything
2819 special; just let the optimization be suppressed. */
2821 if (apply_change_group () && seq)
2822 emit_insn_before (seq, insn);
2827 /* These routines are responsible for converting virtual register references
2828 to the actual hard register references once RTL generation is complete.
2830 The following four variables are used for communication between the
2831 routines. They contain the offsets of the virtual registers from their
2832 respective hard registers. */
2834 static int in_arg_offset;
2835 static int var_offset;
2836 static int dynamic_offset;
2837 static int out_arg_offset;
2838 static int cfa_offset;
2840 /* In most machines, the stack pointer register is equivalent to the bottom
2843 #ifndef STACK_POINTER_OFFSET
2844 #define STACK_POINTER_OFFSET 0
2847 /* If not defined, pick an appropriate default for the offset of dynamically
2848 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2849 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2851 #ifndef STACK_DYNAMIC_OFFSET
2853 /* The bottom of the stack points to the actual arguments. If
2854 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2855 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2856 stack space for register parameters is not pushed by the caller, but
2857 rather part of the fixed stack areas and hence not included in
2858 `current_function_outgoing_args_size'. Nevertheless, we must allow
2859 for it when allocating stack dynamic objects. */
2861 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2862 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2863 ((ACCUMULATE_OUTGOING_ARGS \
2864 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2865 + (STACK_POINTER_OFFSET)) \
2868 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2869 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2870 + (STACK_POINTER_OFFSET))
2874 /* On most machines, the CFA coincides with the first incoming parm. */
2876 #ifndef ARG_POINTER_CFA_OFFSET
2877 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2880 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just
2881 had its address taken. DECL is the decl or SAVE_EXPR for the
2882 object stored in the register, for later use if we do need to force
2883 REG into the stack. REG is overwritten by the MEM like in
2884 put_reg_into_stack. RESCAN is true if previously emitted
2885 instructions must be rescanned and modified now that the REG has
2886 been transformed. */
2889 gen_mem_addressof (reg, decl, rescan)
2894 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2897 /* Calculate this before we start messing with decl's RTL. */
2898 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0;
2900 /* If the original REG was a user-variable, then so is the REG whose
2901 address is being taken. Likewise for unchanging. */
2902 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2903 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2905 PUT_CODE (reg, MEM);
2906 MEM_ATTRS (reg) = 0;
2911 tree type = TREE_TYPE (decl);
2912 enum machine_mode decl_mode
2913 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl)));
2914 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl)
2915 : DECL_RTL_IF_SET (decl));
2917 PUT_MODE (reg, decl_mode);
2919 /* Clear DECL_RTL momentarily so functions below will work
2920 properly, then set it again. */
2921 if (DECL_P (decl) && decl_rtl == reg)
2922 SET_DECL_RTL (decl, 0);
2924 set_mem_attributes (reg, decl, 1);
2925 set_mem_alias_set (reg, set);
2927 if (DECL_P (decl) && decl_rtl == reg)
2928 SET_DECL_RTL (decl, reg);
2931 && (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0)))
2932 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), reg, 0);
2935 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0);
2940 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2943 flush_addressof (decl)
2946 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2947 && DECL_RTL (decl) != 0
2948 && GET_CODE (DECL_RTL (decl)) == MEM
2949 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2950 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2951 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2954 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2957 put_addressof_into_stack (r, ht)
2962 int volatile_p, used_p;
2964 rtx reg = XEXP (r, 0);
2966 if (GET_CODE (reg) != REG)
2969 decl = ADDRESSOF_DECL (r);
2972 type = TREE_TYPE (decl);
2973 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2974 && TREE_THIS_VOLATILE (decl));
2975 used_p = (TREE_USED (decl)
2976 || (DECL_P (decl) && DECL_INITIAL (decl) != 0));
2985 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2986 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2989 /* List of replacements made below in purge_addressof_1 when creating
2990 bitfield insertions. */
2991 static rtx purge_bitfield_addressof_replacements;
2993 /* List of replacements made below in purge_addressof_1 for patterns
2994 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2995 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2996 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2997 enough in complex cases, e.g. when some field values can be
2998 extracted by usage MEM with narrower mode. */
2999 static rtx purge_addressof_replacements;
3001 /* Helper function for purge_addressof. See if the rtx expression at *LOC
3002 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
3003 the stack. If the function returns FALSE then the replacement could not
3004 be made. If MAY_POSTPONE is true and we would not put the addressof
3005 to stack, postpone processing of the insn. */
3008 purge_addressof_1 (loc, insn, force, store, may_postpone, ht)
3011 int force, store, may_postpone;
3020 /* Re-start here to avoid recursion in common cases. */
3027 code = GET_CODE (x);
3029 /* If we don't return in any of the cases below, we will recurse inside
3030 the RTX, which will normally result in any ADDRESSOF being forced into
3034 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1,
3036 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0,
3040 else if (code == ADDRESSOF)
3044 if (GET_CODE (XEXP (x, 0)) != MEM)
3045 put_addressof_into_stack (x, ht);
3047 /* We must create a copy of the rtx because it was created by
3048 overwriting a REG rtx which is always shared. */
3049 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
3050 if (validate_change (insn, loc, sub, 0)
3051 || validate_replace_rtx (x, sub, insn))
3056 /* If SUB is a hard or virtual register, try it as a pseudo-register.
3057 Otherwise, perhaps SUB is an expression, so generate code to compute
3059 if (GET_CODE (sub) == REG && REGNO (sub) <= LAST_VIRTUAL_REGISTER)
3060 sub = copy_to_reg (sub);
3062 sub = force_operand (sub, NULL_RTX);
3064 if (! validate_change (insn, loc, sub, 0)
3065 && ! validate_replace_rtx (x, sub, insn))
3068 insns = get_insns ();
3070 emit_insn_before (insns, insn);
3074 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3076 rtx sub = XEXP (XEXP (x, 0), 0);
3078 if (GET_CODE (sub) == MEM)
3079 sub = adjust_address_nv (sub, GET_MODE (x), 0);
3080 else if (GET_CODE (sub) == REG
3081 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3083 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3085 int size_x, size_sub;
3089 /* Postpone for now, so that we do not emit bitfield arithmetics
3090 unless there is some benefit from it. */
3091 if (!postponed_insns || XEXP (postponed_insns, 0) != insn)
3092 postponed_insns = alloc_INSN_LIST (insn, postponed_insns);
3098 /* When processing REG_NOTES look at the list of
3099 replacements done on the insn to find the register that X
3103 for (tem = purge_bitfield_addressof_replacements;
3105 tem = XEXP (XEXP (tem, 1), 1))
3106 if (rtx_equal_p (x, XEXP (tem, 0)))
3108 *loc = XEXP (XEXP (tem, 1), 0);
3112 /* See comment for purge_addressof_replacements. */
3113 for (tem = purge_addressof_replacements;
3115 tem = XEXP (XEXP (tem, 1), 1))
3116 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3118 rtx z = XEXP (XEXP (tem, 1), 0);
3120 if (GET_MODE (x) == GET_MODE (z)
3121 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3122 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3125 /* It can happen that the note may speak of things
3126 in a wider (or just different) mode than the
3127 code did. This is especially true of
3130 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3133 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3134 && (GET_MODE_SIZE (GET_MODE (x))
3135 > GET_MODE_SIZE (GET_MODE (z))))
3137 /* This can occur as a result in invalid
3138 pointer casts, e.g. float f; ...
3139 *(long long int *)&f.
3140 ??? We could emit a warning here, but
3141 without a line number that wouldn't be
3143 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3146 z = gen_lowpart (GET_MODE (x), z);
3152 /* When we are processing the REG_NOTES of the last instruction
3153 of a libcall, there will be typically no replacements
3154 for that insn; the replacements happened before, piecemeal
3155 fashion. OTOH we are not interested in the details of
3156 this for the REG_EQUAL note, we want to know the big picture,
3157 which can be succinctly described with a simple SUBREG.
3158 Note that removing the REG_EQUAL note is not an option
3159 on the last insn of a libcall, so we must do a replacement. */
3160 if (! purge_addressof_replacements
3161 && ! purge_bitfield_addressof_replacements)
3163 /* In compile/990107-1.c:7 compiled at -O1 -m1 for sh-elf,
3165 (mem:DI (addressof:SI (reg/v:DF 160) 159 0x401c8510)
3166 [0 S8 A32]), which can be expressed with a simple
3168 if ((GET_MODE_SIZE (GET_MODE (x))
3169 == GET_MODE_SIZE (GET_MODE (sub)))
3170 /* Again, invalid pointer casts (as in
3171 compile/990203-1.c) can require paradoxical
3173 || (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3174 && (GET_MODE_SIZE (GET_MODE (x))
3175 > GET_MODE_SIZE (GET_MODE (sub)))))
3177 *loc = gen_rtx_SUBREG (GET_MODE (x), sub, 0);
3180 /* ??? Are there other cases we should handle? */
3182 /* Sometimes we may not be able to find the replacement. For
3183 example when the original insn was a MEM in a wider mode,
3184 and the note is part of a sign extension of a narrowed
3185 version of that MEM. Gcc testcase compile/990829-1.c can
3186 generate an example of this situation. Rather than complain
3187 we return false, which will prompt our caller to remove the
3192 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3193 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3195 /* Do not frob unchanging MEMs. If a later reference forces the
3196 pseudo to the stack, we can wind up with multiple writes to
3197 an unchanging memory, which is invalid. */
3198 if (RTX_UNCHANGING_P (x) && size_x != size_sub)
3201 /* Don't even consider working with paradoxical subregs,
3202 or the moral equivalent seen here. */
3203 else if (size_x <= size_sub
3204 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3206 /* Do a bitfield insertion to mirror what would happen
3213 rtx p = PREV_INSN (insn);
3216 val = gen_reg_rtx (GET_MODE (x));
3217 if (! validate_change (insn, loc, val, 0))
3219 /* Discard the current sequence and put the
3220 ADDRESSOF on stack. */
3226 emit_insn_before (seq, insn);
3227 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3231 store_bit_field (sub, size_x, 0, GET_MODE (x),
3232 val, GET_MODE_SIZE (GET_MODE (sub)));
3234 /* Make sure to unshare any shared rtl that store_bit_field
3235 might have created. */
3236 unshare_all_rtl_again (get_insns ());
3240 p = emit_insn_after (seq, insn);
3241 if (NEXT_INSN (insn))
3242 compute_insns_for_mem (NEXT_INSN (insn),
3243 p ? NEXT_INSN (p) : NULL_RTX,
3248 rtx p = PREV_INSN (insn);
3251 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3252 GET_MODE (x), GET_MODE (x),
3253 GET_MODE_SIZE (GET_MODE (sub)));
3255 if (! validate_change (insn, loc, val, 0))
3257 /* Discard the current sequence and put the
3258 ADDRESSOF on stack. */
3265 emit_insn_before (seq, insn);
3266 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3270 /* Remember the replacement so that the same one can be done
3271 on the REG_NOTES. */
3272 purge_bitfield_addressof_replacements
3273 = gen_rtx_EXPR_LIST (VOIDmode, x,
3276 purge_bitfield_addressof_replacements));
3278 /* We replaced with a reg -- all done. */
3283 else if (validate_change (insn, loc, sub, 0))
3285 /* Remember the replacement so that the same one can be done
3286 on the REG_NOTES. */
3287 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3291 for (tem = purge_addressof_replacements;
3293 tem = XEXP (XEXP (tem, 1), 1))
3294 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3296 XEXP (XEXP (tem, 1), 0) = sub;
3299 purge_addressof_replacements
3300 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3301 gen_rtx_EXPR_LIST (VOIDmode, sub,
3302 purge_addressof_replacements));
3310 /* Scan all subexpressions. */
3311 fmt = GET_RTX_FORMAT (code);
3312 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3315 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0,
3317 else if (*fmt == 'E')
3318 for (j = 0; j < XVECLEN (x, i); j++)
3319 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0,
3326 /* Return a hash value for K, a REG. */
3329 insns_for_mem_hash (k)
3332 /* Use the address of the key for the hash value. */
3333 struct insns_for_mem_entry *m = (struct insns_for_mem_entry *) k;
3334 return htab_hash_pointer (m->key);
3337 /* Return nonzero if K1 and K2 (two REGs) are the same. */
3340 insns_for_mem_comp (k1, k2)
3344 struct insns_for_mem_entry *m1 = (struct insns_for_mem_entry *) k1;
3345 struct insns_for_mem_entry *m2 = (struct insns_for_mem_entry *) k2;
3346 return m1->key == m2->key;
3349 struct insns_for_mem_walk_info
3351 /* The hash table that we are using to record which INSNs use which
3355 /* The INSN we are currently processing. */
3358 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3359 to find the insns that use the REGs in the ADDRESSOFs. */
3363 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3364 that might be used in an ADDRESSOF expression, record this INSN in
3365 the hash table given by DATA (which is really a pointer to an
3366 insns_for_mem_walk_info structure). */
3369 insns_for_mem_walk (r, data)
3373 struct insns_for_mem_walk_info *ifmwi
3374 = (struct insns_for_mem_walk_info *) data;
3375 struct insns_for_mem_entry tmp;
3376 tmp.insns = NULL_RTX;
3378 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3379 && GET_CODE (XEXP (*r, 0)) == REG)
3382 tmp.key = XEXP (*r, 0);
3383 e = htab_find_slot (ifmwi->ht, &tmp, INSERT);
3386 *e = ggc_alloc (sizeof (tmp));
3387 memcpy (*e, &tmp, sizeof (tmp));
3390 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3392 struct insns_for_mem_entry *ifme;
3394 ifme = (struct insns_for_mem_entry *) htab_find (ifmwi->ht, &tmp);
3396 /* If we have not already recorded this INSN, do so now. Since
3397 we process the INSNs in order, we know that if we have
3398 recorded it it must be at the front of the list. */
3399 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3400 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3407 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3408 which REGs in HT. */
3411 compute_insns_for_mem (insns, last_insn, ht)
3417 struct insns_for_mem_walk_info ifmwi;
3420 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3421 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3425 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3429 /* Helper function for purge_addressof called through for_each_rtx.
3430 Returns true iff the rtl is an ADDRESSOF. */
3433 is_addressof (rtl, data)
3435 void *data ATTRIBUTE_UNUSED;
3437 return GET_CODE (*rtl) == ADDRESSOF;
3440 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3441 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3445 purge_addressof (insns)
3451 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3452 requires a fixup pass over the instruction stream to correct
3453 INSNs that depended on the REG being a REG, and not a MEM. But,
3454 these fixup passes are slow. Furthermore, most MEMs are not
3455 mentioned in very many instructions. So, we speed up the process
3456 by pre-calculating which REGs occur in which INSNs; that allows
3457 us to perform the fixup passes much more quickly. */
3458 ht = htab_create_ggc (1000, insns_for_mem_hash, insns_for_mem_comp, NULL);
3459 compute_insns_for_mem (insns, NULL_RTX, ht);
3461 postponed_insns = NULL;
3463 for (insn = insns; insn; insn = NEXT_INSN (insn))
3466 if (! purge_addressof_1 (&PATTERN (insn), insn,
3467 asm_noperands (PATTERN (insn)) > 0, 0, 1, ht))
3468 /* If we could not replace the ADDRESSOFs in the insn,
3469 something is wrong. */
3472 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, 0, ht))
3474 /* If we could not replace the ADDRESSOFs in the insn's notes,
3475 we can just remove the offending notes instead. */
3478 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3480 /* If we find a REG_RETVAL note then the insn is a libcall.
3481 Such insns must have REG_EQUAL notes as well, in order
3482 for later passes of the compiler to work. So it is not
3483 safe to delete the notes here, and instead we abort. */
3484 if (REG_NOTE_KIND (note) == REG_RETVAL)
3486 if (for_each_rtx (¬e, is_addressof, NULL))
3487 remove_note (insn, note);
3492 /* Process the postponed insns. */
3493 while (postponed_insns)
3495 insn = XEXP (postponed_insns, 0);
3496 tmp = postponed_insns;
3497 postponed_insns = XEXP (postponed_insns, 1);
3498 free_INSN_LIST_node (tmp);
3500 if (! purge_addressof_1 (&PATTERN (insn), insn,
3501 asm_noperands (PATTERN (insn)) > 0, 0, 0, ht))
3506 purge_bitfield_addressof_replacements = 0;
3507 purge_addressof_replacements = 0;
3509 /* REGs are shared. purge_addressof will destructively replace a REG
3510 with a MEM, which creates shared MEMs.
3512 Unfortunately, the children of put_reg_into_stack assume that MEMs
3513 referring to the same stack slot are shared (fixup_var_refs and
3514 the associated hash table code).
3516 So, we have to do another unsharing pass after we have flushed any
3517 REGs that had their address taken into the stack.
3519 It may be worth tracking whether or not we converted any REGs into
3520 MEMs to avoid this overhead when it is not needed. */
3521 unshare_all_rtl_again (get_insns ());
3524 /* Convert a SET of a hard subreg to a set of the appropriate hard
3525 register. A subroutine of purge_hard_subreg_sets. */
3528 purge_single_hard_subreg_set (pattern)
3531 rtx reg = SET_DEST (pattern);
3532 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3535 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3536 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3538 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3539 GET_MODE (SUBREG_REG (reg)),
3542 reg = SUBREG_REG (reg);
3546 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3548 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3549 SET_DEST (pattern) = reg;
3553 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3554 only such SETs that we expect to see are those left in because
3555 integrate can't handle sets of parts of a return value register.
3557 We don't use alter_subreg because we only want to eliminate subregs
3558 of hard registers. */
3561 purge_hard_subreg_sets (insn)
3564 for (; insn; insn = NEXT_INSN (insn))
3568 rtx pattern = PATTERN (insn);
3569 switch (GET_CODE (pattern))
3572 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3573 purge_single_hard_subreg_set (pattern);
3578 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3580 rtx inner_pattern = XVECEXP (pattern, 0, j);
3581 if (GET_CODE (inner_pattern) == SET
3582 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3583 purge_single_hard_subreg_set (inner_pattern);
3594 /* Pass through the INSNS of function FNDECL and convert virtual register
3595 references to hard register references. */
3598 instantiate_virtual_regs (fndecl, insns)
3605 /* Compute the offsets to use for this function. */
3606 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3607 var_offset = STARTING_FRAME_OFFSET;
3608 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3609 out_arg_offset = STACK_POINTER_OFFSET;
3610 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3612 /* Scan all variables and parameters of this function. For each that is
3613 in memory, instantiate all virtual registers if the result is a valid
3614 address. If not, we do it later. That will handle most uses of virtual
3615 regs on many machines. */
3616 instantiate_decls (fndecl, 1);
3618 /* Initialize recognition, indicating that volatile is OK. */
3621 /* Scan through all the insns, instantiating every virtual register still
3623 for (insn = insns; insn; insn = NEXT_INSN (insn))
3624 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3625 || GET_CODE (insn) == CALL_INSN)
3627 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3628 if (INSN_DELETED_P (insn))
3630 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3631 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3632 if (GET_CODE (insn) == CALL_INSN)
3633 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3636 /* Past this point all ASM statements should match. Verify that
3637 to avoid failures later in the compilation process. */
3638 if (asm_noperands (PATTERN (insn)) >= 0
3639 && ! check_asm_operands (PATTERN (insn)))
3640 instantiate_virtual_regs_lossage (insn);
3643 /* Instantiate the stack slots for the parm registers, for later use in
3644 addressof elimination. */
3645 for (i = 0; i < max_parm_reg; ++i)
3646 if (parm_reg_stack_loc[i])
3647 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3649 /* Now instantiate the remaining register equivalences for debugging info.
3650 These will not be valid addresses. */
3651 instantiate_decls (fndecl, 0);
3653 /* Indicate that, from now on, assign_stack_local should use
3654 frame_pointer_rtx. */
3655 virtuals_instantiated = 1;
3658 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3659 all virtual registers in their DECL_RTL's.
3661 If VALID_ONLY, do this only if the resulting address is still valid.
3662 Otherwise, always do it. */
3665 instantiate_decls (fndecl, valid_only)
3671 /* Process all parameters of the function. */
3672 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3674 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3675 HOST_WIDE_INT size_rtl;
3677 instantiate_decl (DECL_RTL (decl), size, valid_only);
3679 /* If the parameter was promoted, then the incoming RTL mode may be
3680 larger than the declared type size. We must use the larger of
3682 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3683 size = MAX (size_rtl, size);
3684 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3687 /* Now process all variables defined in the function or its subblocks. */
3688 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3691 /* Subroutine of instantiate_decls: Process all decls in the given
3692 BLOCK node and all its subblocks. */
3695 instantiate_decls_1 (let, valid_only)
3701 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3702 if (DECL_RTL_SET_P (t))
3703 instantiate_decl (DECL_RTL (t),
3704 int_size_in_bytes (TREE_TYPE (t)),
3707 /* Process all subblocks. */
3708 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3709 instantiate_decls_1 (t, valid_only);
3712 /* Subroutine of the preceding procedures: Given RTL representing a
3713 decl and the size of the object, do any instantiation required.
3715 If VALID_ONLY is nonzero, it means that the RTL should only be
3716 changed if the new address is valid. */
3719 instantiate_decl (x, size, valid_only)
3724 enum machine_mode mode;
3727 /* If this is not a MEM, no need to do anything. Similarly if the
3728 address is a constant or a register that is not a virtual register. */
3730 if (x == 0 || GET_CODE (x) != MEM)
3734 if (CONSTANT_P (addr)
3735 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3736 || (GET_CODE (addr) == REG
3737 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3738 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3741 /* If we should only do this if the address is valid, copy the address.
3742 We need to do this so we can undo any changes that might make the
3743 address invalid. This copy is unfortunate, but probably can't be
3747 addr = copy_rtx (addr);
3749 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3751 if (valid_only && size >= 0)
3753 unsigned HOST_WIDE_INT decl_size = size;
3755 /* Now verify that the resulting address is valid for every integer or
3756 floating-point mode up to and including SIZE bytes long. We do this
3757 since the object might be accessed in any mode and frame addresses
3760 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3761 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3762 mode = GET_MODE_WIDER_MODE (mode))
3763 if (! memory_address_p (mode, addr))
3766 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3767 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3768 mode = GET_MODE_WIDER_MODE (mode))
3769 if (! memory_address_p (mode, addr))
3773 /* Put back the address now that we have updated it and we either know
3774 it is valid or we don't care whether it is valid. */
3779 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3780 is a virtual register, return the equivalent hard register and set the
3781 offset indirectly through the pointer. Otherwise, return 0. */
3784 instantiate_new_reg (x, poffset)
3786 HOST_WIDE_INT *poffset;
3789 HOST_WIDE_INT offset;
3791 if (x == virtual_incoming_args_rtx)
3792 new = arg_pointer_rtx, offset = in_arg_offset;
3793 else if (x == virtual_stack_vars_rtx)
3794 new = frame_pointer_rtx, offset = var_offset;
3795 else if (x == virtual_stack_dynamic_rtx)
3796 new = stack_pointer_rtx, offset = dynamic_offset;
3797 else if (x == virtual_outgoing_args_rtx)
3798 new = stack_pointer_rtx, offset = out_arg_offset;
3799 else if (x == virtual_cfa_rtx)
3800 new = arg_pointer_rtx, offset = cfa_offset;
3809 /* Called when instantiate_virtual_regs has failed to update the instruction.
3810 Usually this means that non-matching instruction has been emit, however for
3811 asm statements it may be the problem in the constraints. */
3813 instantiate_virtual_regs_lossage (insn)
3816 if (asm_noperands (PATTERN (insn)) >= 0)
3818 error_for_asm (insn, "impossible constraint in `asm'");
3824 /* Given a pointer to a piece of rtx and an optional pointer to the
3825 containing object, instantiate any virtual registers present in it.
3827 If EXTRA_INSNS, we always do the replacement and generate
3828 any extra insns before OBJECT. If it zero, we do nothing if replacement
3831 Return 1 if we either had nothing to do or if we were able to do the
3832 needed replacement. Return 0 otherwise; we only return zero if
3833 EXTRA_INSNS is zero.
3835 We first try some simple transformations to avoid the creation of extra
3839 instantiate_virtual_regs_1 (loc, object, extra_insns)
3847 HOST_WIDE_INT offset = 0;
3853 /* Re-start here to avoid recursion in common cases. */
3860 /* We may have detected and deleted invalid asm statements. */
3861 if (object && INSN_P (object) && INSN_DELETED_P (object))
3864 code = GET_CODE (x);
3866 /* Check for some special cases. */
3884 /* We are allowed to set the virtual registers. This means that
3885 the actual register should receive the source minus the
3886 appropriate offset. This is used, for example, in the handling
3887 of non-local gotos. */
3888 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3890 rtx src = SET_SRC (x);
3892 /* We are setting the register, not using it, so the relevant
3893 offset is the negative of the offset to use were we using
3896 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3898 /* The only valid sources here are PLUS or REG. Just do
3899 the simplest possible thing to handle them. */
3900 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3902 instantiate_virtual_regs_lossage (object);
3907 if (GET_CODE (src) != REG)
3908 temp = force_operand (src, NULL_RTX);
3911 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3915 emit_insn_before (seq, object);
3918 if (! validate_change (object, &SET_SRC (x), temp, 0)
3920 instantiate_virtual_regs_lossage (object);
3925 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3930 /* Handle special case of virtual register plus constant. */
3931 if (CONSTANT_P (XEXP (x, 1)))
3933 rtx old, new_offset;
3935 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3936 if (GET_CODE (XEXP (x, 0)) == PLUS)
3938 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3940 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3942 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3951 #ifdef POINTERS_EXTEND_UNSIGNED
3952 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3953 we can commute the PLUS and SUBREG because pointers into the
3954 frame are well-behaved. */
3955 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3956 && GET_CODE (XEXP (x, 1)) == CONST_INT
3958 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3960 && validate_change (object, loc,
3961 plus_constant (gen_lowpart (ptr_mode,
3964 + INTVAL (XEXP (x, 1))),
3968 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3970 /* We know the second operand is a constant. Unless the
3971 first operand is a REG (which has been already checked),
3972 it needs to be checked. */
3973 if (GET_CODE (XEXP (x, 0)) != REG)
3981 new_offset = plus_constant (XEXP (x, 1), offset);
3983 /* If the new constant is zero, try to replace the sum with just
3985 if (new_offset == const0_rtx
3986 && validate_change (object, loc, new, 0))
3989 /* Next try to replace the register and new offset.
3990 There are two changes to validate here and we can't assume that
3991 in the case of old offset equals new just changing the register
3992 will yield a valid insn. In the interests of a little efficiency,
3993 however, we only call validate change once (we don't queue up the
3994 changes and then call apply_change_group). */
3998 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3999 : (XEXP (x, 0) = new,
4000 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
4008 /* Otherwise copy the new constant into a register and replace
4009 constant with that register. */
4010 temp = gen_reg_rtx (Pmode);
4012 if (validate_change (object, &XEXP (x, 1), temp, 0))
4013 emit_insn_before (gen_move_insn (temp, new_offset), object);
4016 /* If that didn't work, replace this expression with a
4017 register containing the sum. */
4020 new = gen_rtx_PLUS (Pmode, new, new_offset);
4023 temp = force_operand (new, NULL_RTX);
4027 emit_insn_before (seq, object);
4028 if (! validate_change (object, loc, temp, 0)
4029 && ! validate_replace_rtx (x, temp, object))
4031 instantiate_virtual_regs_lossage (object);
4040 /* Fall through to generic two-operand expression case. */
4046 case DIV: case UDIV:
4047 case MOD: case UMOD:
4048 case AND: case IOR: case XOR:
4049 case ROTATERT: case ROTATE:
4050 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
4052 case GE: case GT: case GEU: case GTU:
4053 case LE: case LT: case LEU: case LTU:
4054 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
4055 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
4060 /* Most cases of MEM that convert to valid addresses have already been
4061 handled by our scan of decls. The only special handling we
4062 need here is to make a copy of the rtx to ensure it isn't being
4063 shared if we have to change it to a pseudo.
4065 If the rtx is a simple reference to an address via a virtual register,
4066 it can potentially be shared. In such cases, first try to make it
4067 a valid address, which can also be shared. Otherwise, copy it and
4070 First check for common cases that need no processing. These are
4071 usually due to instantiation already being done on a previous instance
4075 if (CONSTANT_ADDRESS_P (temp)
4076 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4077 || temp == arg_pointer_rtx
4079 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4080 || temp == hard_frame_pointer_rtx
4082 || temp == frame_pointer_rtx)
4085 if (GET_CODE (temp) == PLUS
4086 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4087 && (XEXP (temp, 0) == frame_pointer_rtx
4088 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4089 || XEXP (temp, 0) == hard_frame_pointer_rtx
4091 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4092 || XEXP (temp, 0) == arg_pointer_rtx
4097 if (temp == virtual_stack_vars_rtx
4098 || temp == virtual_incoming_args_rtx
4099 || (GET_CODE (temp) == PLUS
4100 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4101 && (XEXP (temp, 0) == virtual_stack_vars_rtx
4102 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
4104 /* This MEM may be shared. If the substitution can be done without
4105 the need to generate new pseudos, we want to do it in place
4106 so all copies of the shared rtx benefit. The call below will
4107 only make substitutions if the resulting address is still
4110 Note that we cannot pass X as the object in the recursive call
4111 since the insn being processed may not allow all valid
4112 addresses. However, if we were not passed on object, we can
4113 only modify X without copying it if X will have a valid
4116 ??? Also note that this can still lose if OBJECT is an insn that
4117 has less restrictions on an address that some other insn.
4118 In that case, we will modify the shared address. This case
4119 doesn't seem very likely, though. One case where this could
4120 happen is in the case of a USE or CLOBBER reference, but we
4121 take care of that below. */
4123 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
4124 object ? object : x, 0))
4127 /* Otherwise make a copy and process that copy. We copy the entire
4128 RTL expression since it might be a PLUS which could also be
4130 *loc = x = copy_rtx (x);
4133 /* Fall through to generic unary operation case. */
4136 case STRICT_LOW_PART:
4138 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4139 case SIGN_EXTEND: case ZERO_EXTEND:
4140 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4141 case FLOAT: case FIX:
4142 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4147 case POPCOUNT: case PARITY:
4148 /* These case either have just one operand or we know that we need not
4149 check the rest of the operands. */
4155 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4156 go ahead and make the invalid one, but do it to a copy. For a REG,
4157 just make the recursive call, since there's no chance of a problem. */
4159 if ((GET_CODE (XEXP (x, 0)) == MEM
4160 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4162 || (GET_CODE (XEXP (x, 0)) == REG
4163 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4166 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4171 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4172 in front of this insn and substitute the temporary. */
4173 if ((new = instantiate_new_reg (x, &offset)) != 0)
4175 temp = plus_constant (new, offset);
4176 if (!validate_change (object, loc, temp, 0))
4182 temp = force_operand (temp, NULL_RTX);
4186 emit_insn_before (seq, object);
4187 if (! validate_change (object, loc, temp, 0)
4188 && ! validate_replace_rtx (x, temp, object))
4189 instantiate_virtual_regs_lossage (object);
4196 if (GET_CODE (XEXP (x, 0)) == REG)
4199 else if (GET_CODE (XEXP (x, 0)) == MEM)
4201 /* If we have a (addressof (mem ..)), do any instantiation inside
4202 since we know we'll be making the inside valid when we finally
4203 remove the ADDRESSOF. */
4204 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4213 /* Scan all subexpressions. */
4214 fmt = GET_RTX_FORMAT (code);
4215 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4218 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4221 else if (*fmt == 'E')
4222 for (j = 0; j < XVECLEN (x, i); j++)
4223 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4230 /* Optimization: assuming this function does not receive nonlocal gotos,
4231 delete the handlers for such, as well as the insns to establish
4232 and disestablish them. */
4238 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4240 /* Delete the handler by turning off the flag that would
4241 prevent jump_optimize from deleting it.
4242 Also permit deletion of the nonlocal labels themselves
4243 if nothing local refers to them. */
4244 if (GET_CODE (insn) == CODE_LABEL)
4248 LABEL_PRESERVE_P (insn) = 0;
4250 /* Remove it from the nonlocal_label list, to avoid confusing
4252 for (t = nonlocal_labels, last_t = 0; t;
4253 last_t = t, t = TREE_CHAIN (t))
4254 if (DECL_RTL (TREE_VALUE (t)) == insn)
4259 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4261 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4264 if (GET_CODE (insn) == INSN)
4268 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4269 if (reg_mentioned_p (t, PATTERN (insn)))
4275 || (nonlocal_goto_stack_level != 0
4276 && reg_mentioned_p (nonlocal_goto_stack_level,
4278 delete_related_insns (insn);
4283 /* Return the first insn following those generated by `assign_parms'. */
4286 get_first_nonparm_insn ()
4289 return NEXT_INSN (last_parm_insn);
4290 return get_insns ();
4293 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4294 This means a type for which function calls must pass an address to the
4295 function or get an address back from the function.
4296 EXP may be a type node or an expression (whose type is tested). */
4299 aggregate_value_p (exp)
4302 int i, regno, nregs;
4305 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4307 if (TREE_CODE (type) == VOID_TYPE)
4309 if (RETURN_IN_MEMORY (type))
4311 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4312 and thus can't be returned in registers. */
4313 if (TREE_ADDRESSABLE (type))
4315 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4317 /* Make sure we have suitable call-clobbered regs to return
4318 the value in; if not, we must return it in memory. */
4319 reg = hard_function_value (type, 0, 0);
4321 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4323 if (GET_CODE (reg) != REG)
4326 regno = REGNO (reg);
4327 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4328 for (i = 0; i < nregs; i++)
4329 if (! call_used_regs[regno + i])
4334 /* Assign RTL expressions to the function's parameters.
4335 This may involve copying them into registers and using
4336 those registers as the RTL for them. */
4339 assign_parms (fndecl)
4343 CUMULATIVE_ARGS args_so_far;
4344 /* Total space needed so far for args on the stack,
4345 given as a constant and a tree-expression. */
4346 struct args_size stack_args_size;
4347 tree fntype = TREE_TYPE (fndecl);
4348 tree fnargs = DECL_ARGUMENTS (fndecl);
4349 /* This is used for the arg pointer when referring to stack args. */
4350 rtx internal_arg_pointer;
4351 /* This is a dummy PARM_DECL that we used for the function result if
4352 the function returns a structure. */
4353 tree function_result_decl = 0;
4354 #ifdef SETUP_INCOMING_VARARGS
4355 int varargs_setup = 0;
4357 int reg_parm_stack_space = 0;
4358 rtx conversion_insns = 0;
4360 /* Nonzero if function takes extra anonymous args.
4361 This means the last named arg must be on the stack
4362 right before the anonymous ones. */
4364 = (TYPE_ARG_TYPES (fntype) != 0
4365 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4366 != void_type_node));
4368 current_function_stdarg = stdarg;
4370 /* If the reg that the virtual arg pointer will be translated into is
4371 not a fixed reg or is the stack pointer, make a copy of the virtual
4372 arg pointer, and address parms via the copy. The frame pointer is
4373 considered fixed even though it is not marked as such.
4375 The second time through, simply use ap to avoid generating rtx. */
4377 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4378 || ! (fixed_regs[ARG_POINTER_REGNUM]
4379 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4380 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4382 internal_arg_pointer = virtual_incoming_args_rtx;
4383 current_function_internal_arg_pointer = internal_arg_pointer;
4385 stack_args_size.constant = 0;
4386 stack_args_size.var = 0;
4388 /* If struct value address is treated as the first argument, make it so. */
4389 if (aggregate_value_p (DECL_RESULT (fndecl))
4390 && ! current_function_returns_pcc_struct
4391 && struct_value_incoming_rtx == 0)
4393 tree type = build_pointer_type (TREE_TYPE (fntype));
4395 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4397 DECL_ARG_TYPE (function_result_decl) = type;
4398 TREE_CHAIN (function_result_decl) = fnargs;
4399 fnargs = function_result_decl;
4402 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4403 parm_reg_stack_loc = (rtx *) ggc_alloc_cleared (max_parm_reg * sizeof (rtx));
4405 #ifdef REG_PARM_STACK_SPACE
4406 #ifdef MAYBE_REG_PARM_STACK_SPACE
4407 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
4409 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4413 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4414 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4416 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, fndecl);
4419 /* We haven't yet found an argument that we must push and pretend the
4421 current_function_pretend_args_size = 0;
4423 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4427 enum machine_mode promoted_mode, passed_mode;
4428 enum machine_mode nominal_mode, promoted_nominal_mode;
4430 struct locate_and_pad_arg_data locate;
4431 int passed_pointer = 0;
4432 int did_conversion = 0;
4433 tree passed_type = DECL_ARG_TYPE (parm);
4434 tree nominal_type = TREE_TYPE (parm);
4435 int last_named = 0, named_arg;
4439 /* Set LAST_NAMED if this is last named arg before last
4445 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4446 if (DECL_NAME (tem))
4452 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4453 most machines, if this is a varargs/stdarg function, then we treat
4454 the last named arg as if it were anonymous too. */
4455 named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4457 if (TREE_TYPE (parm) == error_mark_node
4458 /* This can happen after weird syntax errors
4459 or if an enum type is defined among the parms. */
4460 || TREE_CODE (parm) != PARM_DECL
4461 || passed_type == NULL)
4463 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4464 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4465 TREE_USED (parm) = 1;
4469 /* Find mode of arg as it is passed, and mode of arg
4470 as it should be during execution of this function. */
4471 passed_mode = TYPE_MODE (passed_type);
4472 nominal_mode = TYPE_MODE (nominal_type);
4474 /* If the parm's mode is VOID, its value doesn't matter,
4475 and avoid the usual things like emit_move_insn that could crash. */
4476 if (nominal_mode == VOIDmode)
4478 SET_DECL_RTL (parm, const0_rtx);
4479 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4483 /* If the parm is to be passed as a transparent union, use the
4484 type of the first field for the tests below. We have already
4485 verified that the modes are the same. */
4486 if (DECL_TRANSPARENT_UNION (parm)
4487 || (TREE_CODE (passed_type) == UNION_TYPE
4488 && TYPE_TRANSPARENT_UNION (passed_type)))
4489 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4491 /* See if this arg was passed by invisible reference. It is if
4492 it is an object whose size depends on the contents of the
4493 object itself or if the machine requires these objects be passed
4496 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4497 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4498 || TREE_ADDRESSABLE (passed_type)
4499 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4500 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4501 passed_type, named_arg)
4505 passed_type = nominal_type = build_pointer_type (passed_type);
4507 passed_mode = nominal_mode = Pmode;
4509 /* See if the frontend wants to pass this by invisible reference. */
4510 else if (passed_type != nominal_type
4511 && POINTER_TYPE_P (passed_type)
4512 && TREE_TYPE (passed_type) == nominal_type)
4514 nominal_type = passed_type;
4516 passed_mode = nominal_mode = Pmode;
4519 promoted_mode = passed_mode;
4521 #ifdef PROMOTE_FUNCTION_ARGS
4522 /* Compute the mode in which the arg is actually extended to. */
4523 unsignedp = TREE_UNSIGNED (passed_type);
4524 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4527 /* Let machine desc say which reg (if any) the parm arrives in.
4528 0 means it arrives on the stack. */
4529 #ifdef FUNCTION_INCOMING_ARG
4530 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4531 passed_type, named_arg);
4533 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4534 passed_type, named_arg);
4537 if (entry_parm == 0)
4538 promoted_mode = passed_mode;
4540 #ifdef SETUP_INCOMING_VARARGS
4541 /* If this is the last named parameter, do any required setup for
4542 varargs or stdargs. We need to know about the case of this being an
4543 addressable type, in which case we skip the registers it
4544 would have arrived in.
4546 For stdargs, LAST_NAMED will be set for two parameters, the one that
4547 is actually the last named, and the dummy parameter. We only
4548 want to do this action once.
4550 Also, indicate when RTL generation is to be suppressed. */
4551 if (last_named && !varargs_setup)
4553 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4554 current_function_pretend_args_size, 0);
4559 /* Determine parm's home in the stack,
4560 in case it arrives in the stack or we should pretend it did.
4562 Compute the stack position and rtx where the argument arrives
4565 There is one complexity here: If this was a parameter that would
4566 have been passed in registers, but wasn't only because it is
4567 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4568 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4569 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4570 0 as it was the previous time. */
4571 in_regs = entry_parm != 0;
4572 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4575 if (!in_regs && !named_arg)
4577 int pretend_named = PRETEND_OUTGOING_VARARGS_NAMED;
4580 #ifdef FUNCTION_INCOMING_ARG
4581 in_regs = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4583 pretend_named) != 0;
4585 in_regs = FUNCTION_ARG (args_so_far, promoted_mode,
4587 pretend_named) != 0;
4592 /* If this parameter was passed both in registers and in the stack,
4593 use the copy on the stack. */
4594 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4597 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4599 partial = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4600 passed_type, named_arg);
4603 memset (&locate, 0, sizeof (locate));
4604 locate_and_pad_parm (promoted_mode, passed_type, in_regs,
4605 entry_parm ? partial : 0, fndecl,
4606 &stack_args_size, &locate);
4611 /* If we're passing this arg using a reg, make its stack home
4612 the aligned stack slot. */
4614 offset_rtx = ARGS_SIZE_RTX (locate.slot_offset);
4616 offset_rtx = ARGS_SIZE_RTX (locate.offset);
4618 if (offset_rtx == const0_rtx)
4619 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4621 stack_parm = gen_rtx_MEM (promoted_mode,
4622 gen_rtx_PLUS (Pmode,
4623 internal_arg_pointer,
4626 set_mem_attributes (stack_parm, parm, 1);
4628 /* Set also REG_ATTRS if parameter was passed in a register. */
4630 set_reg_attrs_for_parm (entry_parm, stack_parm);
4633 /* If this parm was passed part in regs and part in memory,
4634 pretend it arrived entirely in memory
4635 by pushing the register-part onto the stack.
4637 In the special case of a DImode or DFmode that is split,
4638 we could put it together in a pseudoreg directly,
4639 but for now that's not worth bothering with. */
4643 #ifndef MAYBE_REG_PARM_STACK_SPACE
4644 /* When REG_PARM_STACK_SPACE is nonzero, stack space for
4645 split parameters was allocated by our caller, so we
4646 won't be pushing it in the prolog. */
4647 if (reg_parm_stack_space == 0)
4649 current_function_pretend_args_size
4650 = (((partial * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4651 / (PARM_BOUNDARY / BITS_PER_UNIT)
4652 * (PARM_BOUNDARY / BITS_PER_UNIT));
4654 /* Handle calls that pass values in multiple non-contiguous
4655 locations. The Irix 6 ABI has examples of this. */
4656 if (GET_CODE (entry_parm) == PARALLEL)
4657 emit_group_store (validize_mem (stack_parm), entry_parm,
4658 int_size_in_bytes (TREE_TYPE (parm)));
4661 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
4662 partial, int_size_in_bytes (TREE_TYPE (parm)));
4664 entry_parm = stack_parm;
4667 /* If we didn't decide this parm came in a register,
4668 by default it came on the stack. */
4669 if (entry_parm == 0)
4670 entry_parm = stack_parm;
4672 /* Record permanently how this parm was passed. */
4673 DECL_INCOMING_RTL (parm) = entry_parm;
4675 /* If there is actually space on the stack for this parm,
4676 count it in stack_args_size; otherwise set stack_parm to 0
4677 to indicate there is no preallocated stack slot for the parm. */
4679 if (entry_parm == stack_parm
4680 || (GET_CODE (entry_parm) == PARALLEL
4681 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4682 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4683 /* On some machines, even if a parm value arrives in a register
4684 there is still an (uninitialized) stack slot allocated for it.
4686 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4687 whether this parameter already has a stack slot allocated,
4688 because an arg block exists only if current_function_args_size
4689 is larger than some threshold, and we haven't calculated that
4690 yet. So, for now, we just assume that stack slots never exist
4692 || REG_PARM_STACK_SPACE (fndecl) > 0
4696 stack_args_size.constant += locate.size.constant;
4697 /* locate.size doesn't include the part in regs. */
4699 stack_args_size.constant += current_function_pretend_args_size;
4700 if (locate.size.var)
4701 ADD_PARM_SIZE (stack_args_size, locate.size.var);
4704 /* No stack slot was pushed for this parm. */
4707 /* Update info on where next arg arrives in registers. */
4709 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4710 passed_type, named_arg);
4712 /* If we can't trust the parm stack slot to be aligned enough
4713 for its ultimate type, don't use that slot after entry.
4714 We'll make another stack slot, if we need one. */
4716 unsigned int thisparm_boundary
4717 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4719 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4723 /* If parm was passed in memory, and we need to convert it on entry,
4724 don't store it back in that same slot. */
4725 if (entry_parm == stack_parm
4726 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4729 /* When an argument is passed in multiple locations, we can't
4730 make use of this information, but we can save some copying if
4731 the whole argument is passed in a single register. */
4732 if (GET_CODE (entry_parm) == PARALLEL
4733 && nominal_mode != BLKmode && passed_mode != BLKmode)
4735 int i, len = XVECLEN (entry_parm, 0);
4737 for (i = 0; i < len; i++)
4738 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4739 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4740 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4742 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4744 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4745 DECL_INCOMING_RTL (parm) = entry_parm;
4750 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4751 in the mode in which it arrives.
4752 STACK_PARM is an RTX for a stack slot where the parameter can live
4753 during the function (in case we want to put it there).
4754 STACK_PARM is 0 if no stack slot was pushed for it.
4756 Now output code if necessary to convert ENTRY_PARM to
4757 the type in which this function declares it,
4758 and store that result in an appropriate place,
4759 which may be a pseudo reg, may be STACK_PARM,
4760 or may be a local stack slot if STACK_PARM is 0.
4762 Set DECL_RTL to that place. */
4764 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4766 /* If a BLKmode arrives in registers, copy it to a stack slot.
4767 Handle calls that pass values in multiple non-contiguous
4768 locations. The Irix 6 ABI has examples of this. */
4769 if (GET_CODE (entry_parm) == REG
4770 || GET_CODE (entry_parm) == PARALLEL)
4773 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4776 /* Note that we will be storing an integral number of words.
4777 So we have to be careful to ensure that we allocate an
4778 integral number of words. We do this below in the
4779 assign_stack_local if space was not allocated in the argument
4780 list. If it was, this will not work if PARM_BOUNDARY is not
4781 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4782 if it becomes a problem. */
4784 if (stack_parm == 0)
4787 = assign_stack_local (GET_MODE (entry_parm),
4789 set_mem_attributes (stack_parm, parm, 1);
4792 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4795 /* Handle calls that pass values in multiple non-contiguous
4796 locations. The Irix 6 ABI has examples of this. */
4797 if (GET_CODE (entry_parm) == PARALLEL)
4798 emit_group_store (validize_mem (stack_parm), entry_parm,
4799 int_size_in_bytes (TREE_TYPE (parm)));
4801 move_block_from_reg (REGNO (entry_parm),
4802 validize_mem (stack_parm),
4803 size_stored / UNITS_PER_WORD,
4804 int_size_in_bytes (TREE_TYPE (parm)));
4806 SET_DECL_RTL (parm, stack_parm);
4808 else if (! ((! optimize
4809 && ! DECL_REGISTER (parm))
4810 || TREE_SIDE_EFFECTS (parm)
4811 /* If -ffloat-store specified, don't put explicit
4812 float variables into registers. */
4813 || (flag_float_store
4814 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4815 /* Always assign pseudo to structure return or item passed
4816 by invisible reference. */
4817 || passed_pointer || parm == function_result_decl)
4819 /* Store the parm in a pseudoregister during the function, but we
4820 may need to do it in a wider mode. */
4823 unsigned int regno, regnoi = 0, regnor = 0;
4825 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4827 promoted_nominal_mode
4828 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4830 parmreg = gen_reg_rtx (promoted_nominal_mode);
4831 mark_user_reg (parmreg);
4833 /* If this was an item that we received a pointer to, set DECL_RTL
4837 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4839 set_mem_attributes (x, parm, 1);
4840 SET_DECL_RTL (parm, x);
4844 SET_DECL_RTL (parm, parmreg);
4845 maybe_set_unchanging (DECL_RTL (parm), parm);
4848 /* Copy the value into the register. */
4849 if (nominal_mode != passed_mode
4850 || promoted_nominal_mode != promoted_mode)
4853 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4854 mode, by the caller. We now have to convert it to
4855 NOMINAL_MODE, if different. However, PARMREG may be in
4856 a different mode than NOMINAL_MODE if it is being stored
4859 If ENTRY_PARM is a hard register, it might be in a register
4860 not valid for operating in its mode (e.g., an odd-numbered
4861 register for a DFmode). In that case, moves are the only
4862 thing valid, so we can't do a convert from there. This
4863 occurs when the calling sequence allow such misaligned
4866 In addition, the conversion may involve a call, which could
4867 clobber parameters which haven't been copied to pseudo
4868 registers yet. Therefore, we must first copy the parm to
4869 a pseudo reg here, and save the conversion until after all
4870 parameters have been moved. */
4872 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4874 emit_move_insn (tempreg, validize_mem (entry_parm));
4876 push_to_sequence (conversion_insns);
4877 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4879 if (GET_CODE (tempreg) == SUBREG
4880 && GET_MODE (tempreg) == nominal_mode
4881 && GET_CODE (SUBREG_REG (tempreg)) == REG
4882 && nominal_mode == passed_mode
4883 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4884 && GET_MODE_SIZE (GET_MODE (tempreg))
4885 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4887 /* The argument is already sign/zero extended, so note it
4889 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4890 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4893 /* TREE_USED gets set erroneously during expand_assignment. */
4894 save_tree_used = TREE_USED (parm);
4895 expand_assignment (parm,
4896 make_tree (nominal_type, tempreg), 0, 0);
4897 TREE_USED (parm) = save_tree_used;
4898 conversion_insns = get_insns ();
4903 emit_move_insn (parmreg, validize_mem (entry_parm));
4905 /* If we were passed a pointer but the actual value
4906 can safely live in a register, put it in one. */
4907 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4908 /* If by-reference argument was promoted, demote it. */
4909 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4911 && ! DECL_REGISTER (parm))
4912 || TREE_SIDE_EFFECTS (parm)
4913 /* If -ffloat-store specified, don't put explicit
4914 float variables into registers. */
4915 || (flag_float_store
4916 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4918 /* We can't use nominal_mode, because it will have been set to
4919 Pmode above. We must use the actual mode of the parm. */
4920 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4921 mark_user_reg (parmreg);
4922 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4924 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4925 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4926 push_to_sequence (conversion_insns);
4927 emit_move_insn (tempreg, DECL_RTL (parm));
4929 convert_to_mode (GET_MODE (parmreg),
4932 emit_move_insn (parmreg, DECL_RTL (parm));
4933 conversion_insns = get_insns();
4938 emit_move_insn (parmreg, DECL_RTL (parm));
4939 SET_DECL_RTL (parm, parmreg);
4940 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4944 #ifdef FUNCTION_ARG_CALLEE_COPIES
4945 /* If we are passed an arg by reference and it is our responsibility
4946 to make a copy, do it now.
4947 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4948 original argument, so we must recreate them in the call to
4949 FUNCTION_ARG_CALLEE_COPIES. */
4950 /* ??? Later add code to handle the case that if the argument isn't
4951 modified, don't do the copy. */
4953 else if (passed_pointer
4954 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4955 TYPE_MODE (DECL_ARG_TYPE (parm)),
4956 DECL_ARG_TYPE (parm),
4958 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4961 tree type = DECL_ARG_TYPE (parm);
4963 /* This sequence may involve a library call perhaps clobbering
4964 registers that haven't been copied to pseudos yet. */
4966 push_to_sequence (conversion_insns);
4968 if (!COMPLETE_TYPE_P (type)
4969 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4970 /* This is a variable sized object. */
4971 copy = gen_rtx_MEM (BLKmode,
4972 allocate_dynamic_stack_space
4973 (expr_size (parm), NULL_RTX,
4974 TYPE_ALIGN (type)));
4976 copy = assign_stack_temp (TYPE_MODE (type),
4977 int_size_in_bytes (type), 1);
4978 set_mem_attributes (copy, parm, 1);
4980 store_expr (parm, copy, 0);
4981 emit_move_insn (parmreg, XEXP (copy, 0));
4982 conversion_insns = get_insns ();
4986 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4988 /* In any case, record the parm's desired stack location
4989 in case we later discover it must live in the stack.
4991 If it is a COMPLEX value, store the stack location for both
4994 if (GET_CODE (parmreg) == CONCAT)
4995 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4997 regno = REGNO (parmreg);
4999 if (regno >= max_parm_reg)
5002 int old_max_parm_reg = max_parm_reg;
5004 /* It's slow to expand this one register at a time,
5005 but it's also rare and we need max_parm_reg to be
5006 precisely correct. */
5007 max_parm_reg = regno + 1;
5008 new = (rtx *) ggc_realloc (parm_reg_stack_loc,
5009 max_parm_reg * sizeof (rtx));
5010 memset ((char *) (new + old_max_parm_reg), 0,
5011 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
5012 parm_reg_stack_loc = new;
5015 if (GET_CODE (parmreg) == CONCAT)
5017 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
5019 regnor = REGNO (gen_realpart (submode, parmreg));
5020 regnoi = REGNO (gen_imagpart (submode, parmreg));
5022 if (stack_parm != 0)
5024 parm_reg_stack_loc[regnor]
5025 = gen_realpart (submode, stack_parm);
5026 parm_reg_stack_loc[regnoi]
5027 = gen_imagpart (submode, stack_parm);
5031 parm_reg_stack_loc[regnor] = 0;
5032 parm_reg_stack_loc[regnoi] = 0;
5036 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
5038 /* Mark the register as eliminable if we did no conversion
5039 and it was copied from memory at a fixed offset,
5040 and the arg pointer was not copied to a pseudo-reg.
5041 If the arg pointer is a pseudo reg or the offset formed
5042 an invalid address, such memory-equivalences
5043 as we make here would screw up life analysis for it. */
5044 if (nominal_mode == passed_mode
5047 && GET_CODE (stack_parm) == MEM
5048 && locate.offset.var == 0
5049 && reg_mentioned_p (virtual_incoming_args_rtx,
5050 XEXP (stack_parm, 0)))
5052 rtx linsn = get_last_insn ();
5055 /* Mark complex types separately. */
5056 if (GET_CODE (parmreg) == CONCAT)
5057 /* Scan backwards for the set of the real and
5059 for (sinsn = linsn; sinsn != 0;
5060 sinsn = prev_nonnote_insn (sinsn))
5062 set = single_set (sinsn);
5064 && SET_DEST (set) == regno_reg_rtx [regnoi])
5066 = gen_rtx_EXPR_LIST (REG_EQUIV,
5067 parm_reg_stack_loc[regnoi],
5070 && SET_DEST (set) == regno_reg_rtx [regnor])
5072 = gen_rtx_EXPR_LIST (REG_EQUIV,
5073 parm_reg_stack_loc[regnor],
5076 else if ((set = single_set (linsn)) != 0
5077 && SET_DEST (set) == parmreg)
5079 = gen_rtx_EXPR_LIST (REG_EQUIV,
5080 stack_parm, REG_NOTES (linsn));
5083 /* For pointer data type, suggest pointer register. */
5084 if (POINTER_TYPE_P (TREE_TYPE (parm)))
5085 mark_reg_pointer (parmreg,
5086 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5088 /* If something wants our address, try to use ADDRESSOF. */
5089 if (TREE_ADDRESSABLE (parm))
5091 /* If we end up putting something into the stack,
5092 fixup_var_refs_insns will need to make a pass over
5093 all the instructions. It looks through the pending
5094 sequences -- but it can't see the ones in the
5095 CONVERSION_INSNS, if they're not on the sequence
5096 stack. So, we go back to that sequence, just so that
5097 the fixups will happen. */
5098 push_to_sequence (conversion_insns);
5099 put_var_into_stack (parm, /*rescan=*/true);
5100 conversion_insns = get_insns ();
5106 /* Value must be stored in the stack slot STACK_PARM
5107 during function execution. */
5109 if (promoted_mode != nominal_mode)
5111 /* Conversion is required. */
5112 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
5114 emit_move_insn (tempreg, validize_mem (entry_parm));
5116 push_to_sequence (conversion_insns);
5117 entry_parm = convert_to_mode (nominal_mode, tempreg,
5118 TREE_UNSIGNED (TREE_TYPE (parm)));
5120 /* ??? This may need a big-endian conversion on sparc64. */
5121 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
5123 conversion_insns = get_insns ();
5128 if (entry_parm != stack_parm)
5130 if (stack_parm == 0)
5133 = assign_stack_local (GET_MODE (entry_parm),
5134 GET_MODE_SIZE (GET_MODE (entry_parm)),
5136 set_mem_attributes (stack_parm, parm, 1);
5139 if (promoted_mode != nominal_mode)
5141 push_to_sequence (conversion_insns);
5142 emit_move_insn (validize_mem (stack_parm),
5143 validize_mem (entry_parm));
5144 conversion_insns = get_insns ();
5148 emit_move_insn (validize_mem (stack_parm),
5149 validize_mem (entry_parm));
5152 SET_DECL_RTL (parm, stack_parm);
5156 /* Output all parameter conversion instructions (possibly including calls)
5157 now that all parameters have been copied out of hard registers. */
5158 emit_insn (conversion_insns);
5160 /* If we are receiving a struct value address as the first argument, set up
5161 the RTL for the function result. As this might require code to convert
5162 the transmitted address to Pmode, we do this here to ensure that possible
5163 preliminary conversions of the address have been emitted already. */
5164 if (function_result_decl)
5166 tree result = DECL_RESULT (fndecl);
5167 rtx addr = DECL_RTL (function_result_decl);
5170 #ifdef POINTERS_EXTEND_UNSIGNED
5171 if (GET_MODE (addr) != Pmode)
5172 addr = convert_memory_address (Pmode, addr);
5175 x = gen_rtx_MEM (DECL_MODE (result), addr);
5176 set_mem_attributes (x, result, 1);
5177 SET_DECL_RTL (result, x);
5180 last_parm_insn = get_last_insn ();
5182 current_function_args_size = stack_args_size.constant;
5184 /* Adjust function incoming argument size for alignment and
5187 #ifdef REG_PARM_STACK_SPACE
5188 #ifndef MAYBE_REG_PARM_STACK_SPACE
5189 current_function_args_size = MAX (current_function_args_size,
5190 REG_PARM_STACK_SPACE (fndecl));
5194 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
5196 current_function_args_size
5197 = ((current_function_args_size + STACK_BYTES - 1)
5198 / STACK_BYTES) * STACK_BYTES;
5200 #ifdef ARGS_GROW_DOWNWARD
5201 current_function_arg_offset_rtx
5202 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5203 : expand_expr (size_diffop (stack_args_size.var,
5204 size_int (-stack_args_size.constant)),
5205 NULL_RTX, VOIDmode, 0));
5207 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5210 /* See how many bytes, if any, of its args a function should try to pop
5213 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5214 current_function_args_size);
5216 /* For stdarg.h function, save info about
5217 regs and stack space used by the named args. */
5219 current_function_args_info = args_so_far;
5221 /* Set the rtx used for the function return value. Put this in its
5222 own variable so any optimizers that need this information don't have
5223 to include tree.h. Do this here so it gets done when an inlined
5224 function gets output. */
5226 current_function_return_rtx
5227 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5228 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5230 /* If scalar return value was computed in a pseudo-reg, or was a named
5231 return value that got dumped to the stack, copy that to the hard
5233 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5235 tree decl_result = DECL_RESULT (fndecl);
5236 rtx decl_rtl = DECL_RTL (decl_result);
5238 if (REG_P (decl_rtl)
5239 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5240 : DECL_REGISTER (decl_result))
5244 #ifdef FUNCTION_OUTGOING_VALUE
5245 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5248 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5251 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5252 /* The delay slot scheduler assumes that current_function_return_rtx
5253 holds the hard register containing the return value, not a
5254 temporary pseudo. */
5255 current_function_return_rtx = real_decl_rtl;
5260 /* Indicate whether REGNO is an incoming argument to the current function
5261 that was promoted to a wider mode. If so, return the RTX for the
5262 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5263 that REGNO is promoted from and whether the promotion was signed or
5266 #ifdef PROMOTE_FUNCTION_ARGS
5269 promoted_input_arg (regno, pmode, punsignedp)
5271 enum machine_mode *pmode;
5276 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5277 arg = TREE_CHAIN (arg))
5278 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5279 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5280 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5282 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5283 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5285 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5286 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5287 && mode != DECL_MODE (arg))
5289 *pmode = DECL_MODE (arg);
5290 *punsignedp = unsignedp;
5291 return DECL_INCOMING_RTL (arg);
5300 /* Compute the size and offset from the start of the stacked arguments for a
5301 parm passed in mode PASSED_MODE and with type TYPE.
5303 INITIAL_OFFSET_PTR points to the current offset into the stacked
5306 The starting offset and size for this parm are returned in
5307 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
5308 nonzero, the offset is that of stack slot, which is returned in
5309 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
5310 padding required from the initial offset ptr to the stack slot.
5312 IN_REGS is nonzero if the argument will be passed in registers. It will
5313 never be set if REG_PARM_STACK_SPACE is not defined.
5315 FNDECL is the function in which the argument was defined.
5317 There are two types of rounding that are done. The first, controlled by
5318 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5319 list to be aligned to the specific boundary (in bits). This rounding
5320 affects the initial and starting offsets, but not the argument size.
5322 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5323 optionally rounds the size of the parm to PARM_BOUNDARY. The
5324 initial offset is not affected by this rounding, while the size always
5325 is and the starting offset may be. */
5327 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
5328 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
5329 callers pass in the total size of args so far as
5330 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
5333 locate_and_pad_parm (passed_mode, type, in_regs, partial, fndecl,
5334 initial_offset_ptr, locate)
5335 enum machine_mode passed_mode;
5339 tree fndecl ATTRIBUTE_UNUSED;
5340 struct args_size *initial_offset_ptr;
5341 struct locate_and_pad_arg_data *locate;
5344 enum direction where_pad;
5346 int reg_parm_stack_space = 0;
5347 int part_size_in_regs;
5349 #ifdef REG_PARM_STACK_SPACE
5350 #ifdef MAYBE_REG_PARM_STACK_SPACE
5351 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5353 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5356 /* If we have found a stack parm before we reach the end of the
5357 area reserved for registers, skip that area. */
5360 if (reg_parm_stack_space > 0)
5362 if (initial_offset_ptr->var)
5364 initial_offset_ptr->var
5365 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5366 ssize_int (reg_parm_stack_space));
5367 initial_offset_ptr->constant = 0;
5369 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5370 initial_offset_ptr->constant = reg_parm_stack_space;
5373 #endif /* REG_PARM_STACK_SPACE */
5375 part_size_in_regs = 0;
5376 if (reg_parm_stack_space == 0)
5377 part_size_in_regs = ((partial * UNITS_PER_WORD)
5378 / (PARM_BOUNDARY / BITS_PER_UNIT)
5379 * (PARM_BOUNDARY / BITS_PER_UNIT));
5382 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5383 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5384 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5386 #ifdef ARGS_GROW_DOWNWARD
5387 locate->slot_offset.constant = -initial_offset_ptr->constant;
5388 if (initial_offset_ptr->var)
5389 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
5390 initial_offset_ptr->var);
5394 if (where_pad != none
5395 && (!host_integerp (sizetree, 1)
5396 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5397 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
5398 SUB_PARM_SIZE (locate->slot_offset, s2);
5401 locate->slot_offset.constant += part_size_in_regs;
5404 #ifdef REG_PARM_STACK_SPACE
5405 || REG_PARM_STACK_SPACE (fndecl) > 0
5408 pad_to_arg_alignment (&locate->slot_offset, boundary,
5409 &locate->alignment_pad);
5411 locate->size.constant = (-initial_offset_ptr->constant
5412 - locate->slot_offset.constant);
5413 if (initial_offset_ptr->var)
5414 locate->size.var = size_binop (MINUS_EXPR,
5415 size_binop (MINUS_EXPR,
5417 initial_offset_ptr->var),
5418 locate->slot_offset.var);
5420 /* Pad_below needs the pre-rounded size to know how much to pad
5422 locate->offset = locate->slot_offset;
5423 if (where_pad == downward)
5424 pad_below (&locate->offset, passed_mode, sizetree);
5426 #else /* !ARGS_GROW_DOWNWARD */
5428 #ifdef REG_PARM_STACK_SPACE
5429 || REG_PARM_STACK_SPACE (fndecl) > 0
5432 pad_to_arg_alignment (initial_offset_ptr, boundary,
5433 &locate->alignment_pad);
5434 locate->slot_offset = *initial_offset_ptr;
5436 #ifdef PUSH_ROUNDING
5437 if (passed_mode != BLKmode)
5438 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5441 /* Pad_below needs the pre-rounded size to know how much to pad below
5442 so this must be done before rounding up. */
5443 locate->offset = locate->slot_offset;
5444 if (where_pad == downward)
5445 pad_below (&locate->offset, passed_mode, sizetree);
5447 if (where_pad != none
5448 && (!host_integerp (sizetree, 1)
5449 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5450 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5452 ADD_PARM_SIZE (locate->size, sizetree);
5454 locate->size.constant -= part_size_in_regs;
5455 #endif /* ARGS_GROW_DOWNWARD */
5458 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5459 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5462 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5463 struct args_size *offset_ptr;
5465 struct args_size *alignment_pad;
5467 tree save_var = NULL_TREE;
5468 HOST_WIDE_INT save_constant = 0;
5470 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5472 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5474 save_var = offset_ptr->var;
5475 save_constant = offset_ptr->constant;
5478 alignment_pad->var = NULL_TREE;
5479 alignment_pad->constant = 0;
5481 if (boundary > BITS_PER_UNIT)
5483 if (offset_ptr->var)
5486 #ifdef ARGS_GROW_DOWNWARD
5491 (ARGS_SIZE_TREE (*offset_ptr),
5492 boundary / BITS_PER_UNIT);
5493 /* ARGS_SIZE_TREE includes constant term. */
5494 offset_ptr->constant = 0;
5495 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5496 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5501 offset_ptr->constant =
5502 #ifdef ARGS_GROW_DOWNWARD
5503 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5505 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5507 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5508 alignment_pad->constant = offset_ptr->constant - save_constant;
5514 pad_below (offset_ptr, passed_mode, sizetree)
5515 struct args_size *offset_ptr;
5516 enum machine_mode passed_mode;
5519 if (passed_mode != BLKmode)
5521 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5522 offset_ptr->constant
5523 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5524 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5525 - GET_MODE_SIZE (passed_mode));
5529 if (TREE_CODE (sizetree) != INTEGER_CST
5530 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5532 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5533 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5535 ADD_PARM_SIZE (*offset_ptr, s2);
5536 SUB_PARM_SIZE (*offset_ptr, sizetree);
5541 /* Walk the tree of blocks describing the binding levels within a function
5542 and warn about uninitialized variables.
5543 This is done after calling flow_analysis and before global_alloc
5544 clobbers the pseudo-regs to hard regs. */
5547 uninitialized_vars_warning (block)
5551 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5553 if (warn_uninitialized
5554 && TREE_CODE (decl) == VAR_DECL
5555 /* These warnings are unreliable for and aggregates
5556 because assigning the fields one by one can fail to convince
5557 flow.c that the entire aggregate was initialized.
5558 Unions are troublesome because members may be shorter. */
5559 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5560 && DECL_RTL (decl) != 0
5561 && GET_CODE (DECL_RTL (decl)) == REG
5562 /* Global optimizations can make it difficult to determine if a
5563 particular variable has been initialized. However, a VAR_DECL
5564 with a nonzero DECL_INITIAL had an initializer, so do not
5565 claim it is potentially uninitialized.
5567 We do not care about the actual value in DECL_INITIAL, so we do
5568 not worry that it may be a dangling pointer. */
5569 && DECL_INITIAL (decl) == NULL_TREE
5570 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5571 warning_with_decl (decl,
5572 "`%s' might be used uninitialized in this function");
5574 && TREE_CODE (decl) == VAR_DECL
5575 && DECL_RTL (decl) != 0
5576 && GET_CODE (DECL_RTL (decl)) == REG
5577 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5578 warning_with_decl (decl,
5579 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5581 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5582 uninitialized_vars_warning (sub);
5585 /* Do the appropriate part of uninitialized_vars_warning
5586 but for arguments instead of local variables. */
5589 setjmp_args_warning ()
5592 for (decl = DECL_ARGUMENTS (current_function_decl);
5593 decl; decl = TREE_CHAIN (decl))
5594 if (DECL_RTL (decl) != 0
5595 && GET_CODE (DECL_RTL (decl)) == REG
5596 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5597 warning_with_decl (decl,
5598 "argument `%s' might be clobbered by `longjmp' or `vfork'");
5601 /* If this function call setjmp, put all vars into the stack
5602 unless they were declared `register'. */
5605 setjmp_protect (block)
5609 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5610 if ((TREE_CODE (decl) == VAR_DECL
5611 || TREE_CODE (decl) == PARM_DECL)
5612 && DECL_RTL (decl) != 0
5613 && (GET_CODE (DECL_RTL (decl)) == REG
5614 || (GET_CODE (DECL_RTL (decl)) == MEM
5615 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5616 /* If this variable came from an inline function, it must be
5617 that its life doesn't overlap the setjmp. If there was a
5618 setjmp in the function, it would already be in memory. We
5619 must exclude such variable because their DECL_RTL might be
5620 set to strange things such as virtual_stack_vars_rtx. */
5621 && ! DECL_FROM_INLINE (decl)
5623 #ifdef NON_SAVING_SETJMP
5624 /* If longjmp doesn't restore the registers,
5625 don't put anything in them. */
5629 ! DECL_REGISTER (decl)))
5630 put_var_into_stack (decl, /*rescan=*/true);
5631 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5632 setjmp_protect (sub);
5635 /* Like the previous function, but for args instead of local variables. */
5638 setjmp_protect_args ()
5641 for (decl = DECL_ARGUMENTS (current_function_decl);
5642 decl; decl = TREE_CHAIN (decl))
5643 if ((TREE_CODE (decl) == VAR_DECL
5644 || TREE_CODE (decl) == PARM_DECL)
5645 && DECL_RTL (decl) != 0
5646 && (GET_CODE (DECL_RTL (decl)) == REG
5647 || (GET_CODE (DECL_RTL (decl)) == MEM
5648 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5650 /* If longjmp doesn't restore the registers,
5651 don't put anything in them. */
5652 #ifdef NON_SAVING_SETJMP
5656 ! DECL_REGISTER (decl)))
5657 put_var_into_stack (decl, /*rescan=*/true);
5660 /* Return the context-pointer register corresponding to DECL,
5661 or 0 if it does not need one. */
5664 lookup_static_chain (decl)
5667 tree context = decl_function_context (decl);
5671 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5674 /* We treat inline_function_decl as an alias for the current function
5675 because that is the inline function whose vars, types, etc.
5676 are being merged into the current function.
5677 See expand_inline_function. */
5678 if (context == current_function_decl || context == inline_function_decl)
5679 return virtual_stack_vars_rtx;
5681 for (link = context_display; link; link = TREE_CHAIN (link))
5682 if (TREE_PURPOSE (link) == context)
5683 return RTL_EXPR_RTL (TREE_VALUE (link));
5688 /* Convert a stack slot address ADDR for variable VAR
5689 (from a containing function)
5690 into an address valid in this function (using a static chain). */
5693 fix_lexical_addr (addr, var)
5698 HOST_WIDE_INT displacement;
5699 tree context = decl_function_context (var);
5700 struct function *fp;
5703 /* If this is the present function, we need not do anything. */
5704 if (context == current_function_decl || context == inline_function_decl)
5707 fp = find_function_data (context);
5709 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5710 addr = XEXP (XEXP (addr, 0), 0);
5712 /* Decode given address as base reg plus displacement. */
5713 if (GET_CODE (addr) == REG)
5714 basereg = addr, displacement = 0;
5715 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5716 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5720 /* We accept vars reached via the containing function's
5721 incoming arg pointer and via its stack variables pointer. */
5722 if (basereg == fp->internal_arg_pointer)
5724 /* If reached via arg pointer, get the arg pointer value
5725 out of that function's stack frame.
5727 There are two cases: If a separate ap is needed, allocate a
5728 slot in the outer function for it and dereference it that way.
5729 This is correct even if the real ap is actually a pseudo.
5730 Otherwise, just adjust the offset from the frame pointer to
5733 #ifdef NEED_SEPARATE_AP
5736 addr = get_arg_pointer_save_area (fp);
5737 addr = fix_lexical_addr (XEXP (addr, 0), var);
5738 addr = memory_address (Pmode, addr);
5740 base = gen_rtx_MEM (Pmode, addr);
5741 set_mem_alias_set (base, get_frame_alias_set ());
5742 base = copy_to_reg (base);
5744 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5745 base = lookup_static_chain (var);
5749 else if (basereg == virtual_stack_vars_rtx)
5751 /* This is the same code as lookup_static_chain, duplicated here to
5752 avoid an extra call to decl_function_context. */
5755 for (link = context_display; link; link = TREE_CHAIN (link))
5756 if (TREE_PURPOSE (link) == context)
5758 base = RTL_EXPR_RTL (TREE_VALUE (link));
5766 /* Use same offset, relative to appropriate static chain or argument
5768 return plus_constant (base, displacement);
5771 /* Return the address of the trampoline for entering nested fn FUNCTION.
5772 If necessary, allocate a trampoline (in the stack frame)
5773 and emit rtl to initialize its contents (at entry to this function). */
5776 trampoline_address (function)
5782 struct function *fp;
5785 /* Find an existing trampoline and return it. */
5786 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5787 if (TREE_PURPOSE (link) == function)
5789 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5791 for (fp = outer_function_chain; fp; fp = fp->outer)
5792 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5793 if (TREE_PURPOSE (link) == function)
5795 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5797 return adjust_trampoline_addr (tramp);
5800 /* None exists; we must make one. */
5802 /* Find the `struct function' for the function containing FUNCTION. */
5804 fn_context = decl_function_context (function);
5805 if (fn_context != current_function_decl
5806 && fn_context != inline_function_decl)
5807 fp = find_function_data (fn_context);
5809 /* Allocate run-time space for this trampoline
5810 (usually in the defining function's stack frame). */
5811 #ifdef ALLOCATE_TRAMPOLINE
5812 tramp = ALLOCATE_TRAMPOLINE (fp);
5814 /* If rounding needed, allocate extra space
5815 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5816 #define TRAMPOLINE_REAL_SIZE \
5817 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5818 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5822 /* Record the trampoline for reuse and note it for later initialization
5823 by expand_function_end. */
5826 rtlexp = make_node (RTL_EXPR);
5827 RTL_EXPR_RTL (rtlexp) = tramp;
5828 fp->x_trampoline_list = tree_cons (function, rtlexp,
5829 fp->x_trampoline_list);
5833 /* Make the RTL_EXPR node temporary, not momentary, so that the
5834 trampoline_list doesn't become garbage. */
5835 rtlexp = make_node (RTL_EXPR);
5837 RTL_EXPR_RTL (rtlexp) = tramp;
5838 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5841 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5842 return adjust_trampoline_addr (tramp);
5845 /* Given a trampoline address,
5846 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5849 round_trampoline_addr (tramp)
5852 /* Round address up to desired boundary. */
5853 rtx temp = gen_reg_rtx (Pmode);
5854 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
5855 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5857 temp = expand_simple_binop (Pmode, PLUS, tramp, addend,
5858 temp, 0, OPTAB_LIB_WIDEN);
5859 tramp = expand_simple_binop (Pmode, AND, temp, mask,
5860 temp, 0, OPTAB_LIB_WIDEN);
5865 /* Given a trampoline address, round it then apply any
5866 platform-specific adjustments so that the result can be used for a
5870 adjust_trampoline_addr (tramp)
5873 tramp = round_trampoline_addr (tramp);
5874 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5875 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5880 /* Put all this function's BLOCK nodes including those that are chained
5881 onto the first block into a vector, and return it.
5882 Also store in each NOTE for the beginning or end of a block
5883 the index of that block in the vector.
5884 The arguments are BLOCK, the chain of top-level blocks of the function,
5885 and INSNS, the insn chain of the function. */
5891 tree *block_vector, *last_block_vector;
5893 tree block = DECL_INITIAL (current_function_decl);
5898 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5899 depth-first order. */
5900 block_vector = get_block_vector (block, &n_blocks);
5901 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5903 last_block_vector = identify_blocks_1 (get_insns (),
5905 block_vector + n_blocks,
5908 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5909 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5910 if (0 && last_block_vector != block_vector + n_blocks)
5913 free (block_vector);
5917 /* Subroutine of identify_blocks. Do the block substitution on the
5918 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5920 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5921 BLOCK_VECTOR is incremented for each block seen. */
5924 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5927 tree *end_block_vector;
5928 tree *orig_block_stack;
5931 tree *block_stack = orig_block_stack;
5933 for (insn = insns; insn; insn = NEXT_INSN (insn))
5935 if (GET_CODE (insn) == NOTE)
5937 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5941 /* If there are more block notes than BLOCKs, something
5943 if (block_vector == end_block_vector)
5946 b = *block_vector++;
5947 NOTE_BLOCK (insn) = b;
5950 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5952 /* If there are more NOTE_INSN_BLOCK_ENDs than
5953 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5954 if (block_stack == orig_block_stack)
5957 NOTE_BLOCK (insn) = *--block_stack;
5960 else if (GET_CODE (insn) == CALL_INSN
5961 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5963 rtx cp = PATTERN (insn);
5965 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5966 end_block_vector, block_stack);
5968 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5969 end_block_vector, block_stack);
5971 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5972 end_block_vector, block_stack);
5976 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5977 something is badly wrong. */
5978 if (block_stack != orig_block_stack)
5981 return block_vector;
5984 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5985 and create duplicate blocks. */
5986 /* ??? Need an option to either create block fragments or to create
5987 abstract origin duplicates of a source block. It really depends
5988 on what optimization has been performed. */
5993 tree block = DECL_INITIAL (current_function_decl);
5994 varray_type block_stack;
5996 if (block == NULL_TREE)
5999 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
6001 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
6002 reorder_blocks_0 (block);
6004 /* Prune the old trees away, so that they don't get in the way. */
6005 BLOCK_SUBBLOCKS (block) = NULL_TREE;
6006 BLOCK_CHAIN (block) = NULL_TREE;
6008 /* Recreate the block tree from the note nesting. */
6009 reorder_blocks_1 (get_insns (), block, &block_stack);
6010 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
6012 /* Remove deleted blocks from the block fragment chains. */
6013 reorder_fix_fragments (block);
6016 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
6019 reorder_blocks_0 (block)
6024 TREE_ASM_WRITTEN (block) = 0;
6025 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
6026 block = BLOCK_CHAIN (block);
6031 reorder_blocks_1 (insns, current_block, p_block_stack)
6034 varray_type *p_block_stack;
6038 for (insn = insns; insn; insn = NEXT_INSN (insn))
6040 if (GET_CODE (insn) == NOTE)
6042 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
6044 tree block = NOTE_BLOCK (insn);
6046 /* If we have seen this block before, that means it now
6047 spans multiple address regions. Create a new fragment. */
6048 if (TREE_ASM_WRITTEN (block))
6050 tree new_block = copy_node (block);
6053 origin = (BLOCK_FRAGMENT_ORIGIN (block)
6054 ? BLOCK_FRAGMENT_ORIGIN (block)
6056 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
6057 BLOCK_FRAGMENT_CHAIN (new_block)
6058 = BLOCK_FRAGMENT_CHAIN (origin);
6059 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
6061 NOTE_BLOCK (insn) = new_block;
6065 BLOCK_SUBBLOCKS (block) = 0;
6066 TREE_ASM_WRITTEN (block) = 1;
6067 /* When there's only one block for the entire function,
6068 current_block == block and we mustn't do this, it
6069 will cause infinite recursion. */
6070 if (block != current_block)
6072 BLOCK_SUPERCONTEXT (block) = current_block;
6073 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
6074 BLOCK_SUBBLOCKS (current_block) = block;
6075 current_block = block;
6077 VARRAY_PUSH_TREE (*p_block_stack, block);
6079 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
6081 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
6082 VARRAY_POP (*p_block_stack);
6083 BLOCK_SUBBLOCKS (current_block)
6084 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
6085 current_block = BLOCK_SUPERCONTEXT (current_block);
6088 else if (GET_CODE (insn) == CALL_INSN
6089 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
6091 rtx cp = PATTERN (insn);
6092 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
6094 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
6096 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
6101 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
6102 appears in the block tree, select one of the fragments to become
6103 the new origin block. */
6106 reorder_fix_fragments (block)
6111 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
6112 tree new_origin = NULL_TREE;
6116 if (! TREE_ASM_WRITTEN (dup_origin))
6118 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
6120 /* Find the first of the remaining fragments. There must
6121 be at least one -- the current block. */
6122 while (! TREE_ASM_WRITTEN (new_origin))
6123 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
6124 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
6127 else if (! dup_origin)
6130 /* Re-root the rest of the fragments to the new origin. In the
6131 case that DUP_ORIGIN was null, that means BLOCK was the origin
6132 of a chain of fragments and we want to remove those fragments
6133 that didn't make it to the output. */
6136 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
6141 if (TREE_ASM_WRITTEN (chain))
6143 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
6145 pp = &BLOCK_FRAGMENT_CHAIN (chain);
6147 chain = BLOCK_FRAGMENT_CHAIN (chain);
6152 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
6153 block = BLOCK_CHAIN (block);
6157 /* Reverse the order of elements in the chain T of blocks,
6158 and return the new head of the chain (old last element). */
6164 tree prev = 0, decl, next;
6165 for (decl = t; decl; decl = next)
6167 next = BLOCK_CHAIN (decl);
6168 BLOCK_CHAIN (decl) = prev;
6174 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6175 non-NULL, list them all into VECTOR, in a depth-first preorder
6176 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6180 all_blocks (block, vector)
6188 TREE_ASM_WRITTEN (block) = 0;
6190 /* Record this block. */
6192 vector[n_blocks] = block;
6196 /* Record the subblocks, and their subblocks... */
6197 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6198 vector ? vector + n_blocks : 0);
6199 block = BLOCK_CHAIN (block);
6205 /* Return a vector containing all the blocks rooted at BLOCK. The
6206 number of elements in the vector is stored in N_BLOCKS_P. The
6207 vector is dynamically allocated; it is the caller's responsibility
6208 to call `free' on the pointer returned. */
6211 get_block_vector (block, n_blocks_p)
6217 *n_blocks_p = all_blocks (block, NULL);
6218 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
6219 all_blocks (block, block_vector);
6221 return block_vector;
6224 static GTY(()) int next_block_index = 2;
6226 /* Set BLOCK_NUMBER for all the blocks in FN. */
6236 /* For SDB and XCOFF debugging output, we start numbering the blocks
6237 from 1 within each function, rather than keeping a running
6239 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6240 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6241 next_block_index = 1;
6244 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6246 /* The top-level BLOCK isn't numbered at all. */
6247 for (i = 1; i < n_blocks; ++i)
6248 /* We number the blocks from two. */
6249 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6251 free (block_vector);
6256 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6259 debug_find_var_in_block_tree (var, block)
6265 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6269 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6271 tree ret = debug_find_var_in_block_tree (var, t);
6279 /* Allocate a function structure and reset its contents to the defaults. */
6282 prepare_function_start ()
6284 cfun = (struct function *) ggc_alloc_cleared (sizeof (struct function));
6286 init_stmt_for_function ();
6287 init_eh_for_function ();
6289 cse_not_expected = ! optimize;
6291 /* Caller save not needed yet. */
6292 caller_save_needed = 0;
6294 /* No stack slots have been made yet. */
6295 stack_slot_list = 0;
6297 current_function_has_nonlocal_label = 0;
6298 current_function_has_nonlocal_goto = 0;
6300 /* There is no stack slot for handling nonlocal gotos. */
6301 nonlocal_goto_handler_slots = 0;
6302 nonlocal_goto_stack_level = 0;
6304 /* No labels have been declared for nonlocal use. */
6305 nonlocal_labels = 0;
6306 nonlocal_goto_handler_labels = 0;
6308 /* No function calls so far in this function. */
6309 function_call_count = 0;
6311 /* No parm regs have been allocated.
6312 (This is important for output_inline_function.) */
6313 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6315 /* Initialize the RTL mechanism. */
6318 /* Initialize the queue of pending postincrement and postdecrements,
6319 and some other info in expr.c. */
6322 /* We haven't done register allocation yet. */
6325 init_varasm_status (cfun);
6327 /* Clear out data used for inlining. */
6328 cfun->inlinable = 0;
6329 cfun->original_decl_initial = 0;
6330 cfun->original_arg_vector = 0;
6332 cfun->stack_alignment_needed = STACK_BOUNDARY;
6333 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6335 /* Set if a call to setjmp is seen. */
6336 current_function_calls_setjmp = 0;
6338 /* Set if a call to longjmp is seen. */
6339 current_function_calls_longjmp = 0;
6341 current_function_calls_alloca = 0;
6342 current_function_calls_eh_return = 0;
6343 current_function_calls_constant_p = 0;
6344 current_function_contains_functions = 0;
6345 current_function_is_leaf = 0;
6346 current_function_nothrow = 0;
6347 current_function_sp_is_unchanging = 0;
6348 current_function_uses_only_leaf_regs = 0;
6349 current_function_has_computed_jump = 0;
6350 current_function_is_thunk = 0;
6352 current_function_returns_pcc_struct = 0;
6353 current_function_returns_struct = 0;
6354 current_function_epilogue_delay_list = 0;
6355 current_function_uses_const_pool = 0;
6356 current_function_uses_pic_offset_table = 0;
6357 current_function_cannot_inline = 0;
6359 /* We have not yet needed to make a label to jump to for tail-recursion. */
6360 tail_recursion_label = 0;
6362 /* We haven't had a need to make a save area for ap yet. */
6363 arg_pointer_save_area = 0;
6365 /* No stack slots allocated yet. */
6368 /* No SAVE_EXPRs in this function yet. */
6371 /* No RTL_EXPRs in this function yet. */
6374 /* Set up to allocate temporaries. */
6377 /* Indicate that we need to distinguish between the return value of the
6378 present function and the return value of a function being called. */
6379 rtx_equal_function_value_matters = 1;
6381 /* Indicate that we have not instantiated virtual registers yet. */
6382 virtuals_instantiated = 0;
6384 /* Indicate that we want CONCATs now. */
6385 generating_concat_p = 1;
6387 /* Indicate we have no need of a frame pointer yet. */
6388 frame_pointer_needed = 0;
6390 /* By default assume not stdarg. */
6391 current_function_stdarg = 0;
6393 /* We haven't made any trampolines for this function yet. */
6394 trampoline_list = 0;
6396 init_pending_stack_adjust ();
6397 inhibit_defer_pop = 0;
6399 current_function_outgoing_args_size = 0;
6401 current_function_funcdef_no = funcdef_no++;
6403 cfun->arc_profile = profile_arc_flag || flag_test_coverage;
6405 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
6407 cfun->max_jumptable_ents = 0;
6409 (*lang_hooks.function.init) (cfun);
6410 if (init_machine_status)
6411 cfun->machine = (*init_machine_status) ();
6414 /* Initialize the rtl expansion mechanism so that we can do simple things
6415 like generate sequences. This is used to provide a context during global
6416 initialization of some passes. */
6418 init_dummy_function_start ()
6420 prepare_function_start ();
6423 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6424 and initialize static variables for generating RTL for the statements
6428 init_function_start (subr, filename, line)
6430 const char *filename;
6433 prepare_function_start ();
6435 current_function_name = (*lang_hooks.decl_printable_name) (subr, 2);
6438 /* Nonzero if this is a nested function that uses a static chain. */
6440 current_function_needs_context
6441 = (decl_function_context (current_function_decl) != 0
6442 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6444 /* Within function body, compute a type's size as soon it is laid out. */
6445 immediate_size_expand++;
6447 /* Prevent ever trying to delete the first instruction of a function.
6448 Also tell final how to output a linenum before the function prologue.
6449 Note linenums could be missing, e.g. when compiling a Java .class file. */
6451 emit_line_note (filename, line);
6453 /* Make sure first insn is a note even if we don't want linenums.
6454 This makes sure the first insn will never be deleted.
6455 Also, final expects a note to appear there. */
6456 emit_note (NULL, NOTE_INSN_DELETED);
6458 /* Set flags used by final.c. */
6459 if (aggregate_value_p (DECL_RESULT (subr)))
6461 #ifdef PCC_STATIC_STRUCT_RETURN
6462 current_function_returns_pcc_struct = 1;
6464 current_function_returns_struct = 1;
6467 /* Warn if this value is an aggregate type,
6468 regardless of which calling convention we are using for it. */
6469 if (warn_aggregate_return
6470 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6471 warning ("function returns an aggregate");
6473 current_function_returns_pointer
6474 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
6477 /* Make sure all values used by the optimization passes have sane
6480 init_function_for_compilation ()
6484 /* No prologue/epilogue insns yet. */
6485 VARRAY_GROW (prologue, 0);
6486 VARRAY_GROW (epilogue, 0);
6487 VARRAY_GROW (sibcall_epilogue, 0);
6490 /* Expand a call to __main at the beginning of a possible main function. */
6492 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6493 #undef HAS_INIT_SECTION
6494 #define HAS_INIT_SECTION
6498 expand_main_function ()
6500 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6501 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6503 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6507 /* Forcibly align the stack. */
6508 #ifdef STACK_GROWS_DOWNWARD
6509 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6510 stack_pointer_rtx, 1, OPTAB_WIDEN);
6512 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6513 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6514 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6515 stack_pointer_rtx, 1, OPTAB_WIDEN);
6517 if (tmp != stack_pointer_rtx)
6518 emit_move_insn (stack_pointer_rtx, tmp);
6520 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6521 tmp = force_reg (Pmode, const0_rtx);
6522 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6526 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6527 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6530 emit_insn_before (seq, tmp);
6536 #ifndef HAS_INIT_SECTION
6537 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
6541 /* The PENDING_SIZES represent the sizes of variable-sized types.
6542 Create RTL for the various sizes now (using temporary variables),
6543 so that we can refer to the sizes from the RTL we are generating
6544 for the current function. The PENDING_SIZES are a TREE_LIST. The
6545 TREE_VALUE of each node is a SAVE_EXPR. */
6548 expand_pending_sizes (pending_sizes)
6553 /* Evaluate now the sizes of any types declared among the arguments. */
6554 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6556 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6557 /* Flush the queue in case this parameter declaration has
6563 /* Start the RTL for a new function, and set variables used for
6565 SUBR is the FUNCTION_DECL node.
6566 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6567 the function's parameters, which must be run at any return statement. */
6570 expand_function_start (subr, parms_have_cleanups)
6572 int parms_have_cleanups;
6575 rtx last_ptr = NULL_RTX;
6577 /* Make sure volatile mem refs aren't considered
6578 valid operands of arithmetic insns. */
6579 init_recog_no_volatile ();
6581 current_function_instrument_entry_exit
6582 = (flag_instrument_function_entry_exit
6583 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6585 current_function_profile
6587 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6589 current_function_limit_stack
6590 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6592 /* If function gets a static chain arg, store it in the stack frame.
6593 Do this first, so it gets the first stack slot offset. */
6594 if (current_function_needs_context)
6596 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6598 /* Delay copying static chain if it is not a register to avoid
6599 conflicts with regs used for parameters. */
6600 if (! SMALL_REGISTER_CLASSES
6601 || GET_CODE (static_chain_incoming_rtx) == REG)
6602 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6605 /* If the parameters of this function need cleaning up, get a label
6606 for the beginning of the code which executes those cleanups. This must
6607 be done before doing anything with return_label. */
6608 if (parms_have_cleanups)
6609 cleanup_label = gen_label_rtx ();
6613 /* Make the label for return statements to jump to. Do not special
6614 case machines with special return instructions -- they will be
6615 handled later during jump, ifcvt, or epilogue creation. */
6616 return_label = gen_label_rtx ();
6618 /* Initialize rtx used to return the value. */
6619 /* Do this before assign_parms so that we copy the struct value address
6620 before any library calls that assign parms might generate. */
6622 /* Decide whether to return the value in memory or in a register. */
6623 if (aggregate_value_p (DECL_RESULT (subr)))
6625 /* Returning something that won't go in a register. */
6626 rtx value_address = 0;
6628 #ifdef PCC_STATIC_STRUCT_RETURN
6629 if (current_function_returns_pcc_struct)
6631 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6632 value_address = assemble_static_space (size);
6637 /* Expect to be passed the address of a place to store the value.
6638 If it is passed as an argument, assign_parms will take care of
6640 if (struct_value_incoming_rtx)
6642 value_address = gen_reg_rtx (Pmode);
6643 emit_move_insn (value_address, struct_value_incoming_rtx);
6648 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6649 set_mem_attributes (x, DECL_RESULT (subr), 1);
6650 SET_DECL_RTL (DECL_RESULT (subr), x);
6653 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6654 /* If return mode is void, this decl rtl should not be used. */
6655 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6658 /* Compute the return values into a pseudo reg, which we will copy
6659 into the true return register after the cleanups are done. */
6661 /* In order to figure out what mode to use for the pseudo, we
6662 figure out what the mode of the eventual return register will
6663 actually be, and use that. */
6665 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6668 /* Structures that are returned in registers are not aggregate_value_p,
6669 so we may see a PARALLEL or a REG. */
6670 if (REG_P (hard_reg))
6671 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6672 else if (GET_CODE (hard_reg) == PARALLEL)
6673 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
6677 /* Set DECL_REGISTER flag so that expand_function_end will copy the
6678 result to the real return register(s). */
6679 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6682 /* Initialize rtx for parameters and local variables.
6683 In some cases this requires emitting insns. */
6685 assign_parms (subr);
6687 /* Copy the static chain now if it wasn't a register. The delay is to
6688 avoid conflicts with the parameter passing registers. */
6690 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6691 if (GET_CODE (static_chain_incoming_rtx) != REG)
6692 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6694 /* The following was moved from init_function_start.
6695 The move is supposed to make sdb output more accurate. */
6696 /* Indicate the beginning of the function body,
6697 as opposed to parm setup. */
6698 emit_note (NULL, NOTE_INSN_FUNCTION_BEG);
6700 if (GET_CODE (get_last_insn ()) != NOTE)
6701 emit_note (NULL, NOTE_INSN_DELETED);
6702 parm_birth_insn = get_last_insn ();
6704 context_display = 0;
6705 if (current_function_needs_context)
6707 /* Fetch static chain values for containing functions. */
6708 tem = decl_function_context (current_function_decl);
6709 /* Copy the static chain pointer into a pseudo. If we have
6710 small register classes, copy the value from memory if
6711 static_chain_incoming_rtx is a REG. */
6714 /* If the static chain originally came in a register, put it back
6715 there, then move it out in the next insn. The reason for
6716 this peculiar code is to satisfy function integration. */
6717 if (SMALL_REGISTER_CLASSES
6718 && GET_CODE (static_chain_incoming_rtx) == REG)
6719 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6720 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6725 tree rtlexp = make_node (RTL_EXPR);
6727 RTL_EXPR_RTL (rtlexp) = last_ptr;
6728 context_display = tree_cons (tem, rtlexp, context_display);
6729 tem = decl_function_context (tem);
6732 /* Chain thru stack frames, assuming pointer to next lexical frame
6733 is found at the place we always store it. */
6734 #ifdef FRAME_GROWS_DOWNWARD
6735 last_ptr = plus_constant (last_ptr,
6736 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6738 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6739 set_mem_alias_set (last_ptr, get_frame_alias_set ());
6740 last_ptr = copy_to_reg (last_ptr);
6742 /* If we are not optimizing, ensure that we know that this
6743 piece of context is live over the entire function. */
6745 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6750 if (current_function_instrument_entry_exit)
6752 rtx fun = DECL_RTL (current_function_decl);
6753 if (GET_CODE (fun) == MEM)
6754 fun = XEXP (fun, 0);
6757 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode,
6759 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6761 hard_frame_pointer_rtx),
6765 if (current_function_profile)
6768 PROFILE_HOOK (current_function_funcdef_no);
6772 /* After the display initializations is where the tail-recursion label
6773 should go, if we end up needing one. Ensure we have a NOTE here
6774 since some things (like trampolines) get placed before this. */
6775 tail_recursion_reentry = emit_note (NULL, NOTE_INSN_DELETED);
6777 /* Evaluate now the sizes of any types declared among the arguments. */
6778 expand_pending_sizes (nreverse (get_pending_sizes ()));
6780 /* Make sure there is a line number after the function entry setup code. */
6781 force_next_line_note ();
6784 /* Undo the effects of init_dummy_function_start. */
6786 expand_dummy_function_end ()
6788 /* End any sequences that failed to be closed due to syntax errors. */
6789 while (in_sequence_p ())
6792 /* Outside function body, can't compute type's actual size
6793 until next function's body starts. */
6795 free_after_parsing (cfun);
6796 free_after_compilation (cfun);
6800 /* Call DOIT for each hard register used as a return value from
6801 the current function. */
6804 diddle_return_value (doit, arg)
6805 void (*doit) PARAMS ((rtx, void *));
6808 rtx outgoing = current_function_return_rtx;
6813 if (GET_CODE (outgoing) == REG)
6814 (*doit) (outgoing, arg);
6815 else if (GET_CODE (outgoing) == PARALLEL)
6819 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6821 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6823 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6830 do_clobber_return_reg (reg, arg)
6832 void *arg ATTRIBUTE_UNUSED;
6834 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6838 clobber_return_register ()
6840 diddle_return_value (do_clobber_return_reg, NULL);
6842 /* In case we do use pseudo to return value, clobber it too. */
6843 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6845 tree decl_result = DECL_RESULT (current_function_decl);
6846 rtx decl_rtl = DECL_RTL (decl_result);
6847 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6849 do_clobber_return_reg (decl_rtl, NULL);
6855 do_use_return_reg (reg, arg)
6857 void *arg ATTRIBUTE_UNUSED;
6859 emit_insn (gen_rtx_USE (VOIDmode, reg));
6863 use_return_register ()
6865 diddle_return_value (do_use_return_reg, NULL);
6868 static GTY(()) rtx initial_trampoline;
6870 /* Generate RTL for the end of the current function.
6871 FILENAME and LINE are the current position in the source file.
6873 It is up to language-specific callers to do cleanups for parameters--
6874 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6877 expand_function_end (filename, line, end_bindings)
6878 const char *filename;
6885 finish_expr_for_function ();
6887 /* If arg_pointer_save_area was referenced only from a nested
6888 function, we will not have initialized it yet. Do that now. */
6889 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6890 get_arg_pointer_save_area (cfun);
6892 #ifdef NON_SAVING_SETJMP
6893 /* Don't put any variables in registers if we call setjmp
6894 on a machine that fails to restore the registers. */
6895 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6897 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6898 setjmp_protect (DECL_INITIAL (current_function_decl));
6900 setjmp_protect_args ();
6904 /* Initialize any trampolines required by this function. */
6905 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6907 tree function = TREE_PURPOSE (link);
6908 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6909 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6910 #ifdef TRAMPOLINE_TEMPLATE
6915 #ifdef TRAMPOLINE_TEMPLATE
6916 /* First make sure this compilation has a template for
6917 initializing trampolines. */
6918 if (initial_trampoline == 0)
6921 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6922 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
6926 /* Generate insns to initialize the trampoline. */
6928 tramp = round_trampoline_addr (XEXP (tramp, 0));
6929 #ifdef TRAMPOLINE_TEMPLATE
6930 blktramp = replace_equiv_address (initial_trampoline, tramp);
6931 emit_block_move (blktramp, initial_trampoline,
6932 GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL);
6934 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6938 /* Put those insns at entry to the containing function (this one). */
6939 emit_insn_before (seq, tail_recursion_reentry);
6942 /* If we are doing stack checking and this function makes calls,
6943 do a stack probe at the start of the function to ensure we have enough
6944 space for another stack frame. */
6945 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6949 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6950 if (GET_CODE (insn) == CALL_INSN)
6953 probe_stack_range (STACK_CHECK_PROTECT,
6954 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6957 emit_insn_before (seq, tail_recursion_reentry);
6962 /* Possibly warn about unused parameters. */
6963 if (warn_unused_parameter)
6967 for (decl = DECL_ARGUMENTS (current_function_decl);
6968 decl; decl = TREE_CHAIN (decl))
6969 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6970 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6971 warning_with_decl (decl, "unused parameter `%s'");
6974 /* Delete handlers for nonlocal gotos if nothing uses them. */
6975 if (nonlocal_goto_handler_slots != 0
6976 && ! current_function_has_nonlocal_label)
6979 /* End any sequences that failed to be closed due to syntax errors. */
6980 while (in_sequence_p ())
6983 /* Outside function body, can't compute type's actual size
6984 until next function's body starts. */
6985 immediate_size_expand--;
6987 clear_pending_stack_adjust ();
6988 do_pending_stack_adjust ();
6990 /* Mark the end of the function body.
6991 If control reaches this insn, the function can drop through
6992 without returning a value. */
6993 emit_note (NULL, NOTE_INSN_FUNCTION_END);
6995 /* Must mark the last line number note in the function, so that the test
6996 coverage code can avoid counting the last line twice. This just tells
6997 the code to ignore the immediately following line note, since there
6998 already exists a copy of this note somewhere above. This line number
6999 note is still needed for debugging though, so we can't delete it. */
7000 if (flag_test_coverage)
7001 emit_note (NULL, NOTE_INSN_REPEATED_LINE_NUMBER);
7003 /* Output a linenumber for the end of the function.
7004 SDB depends on this. */
7005 emit_line_note_force (filename, line);
7007 /* Before the return label (if any), clobber the return
7008 registers so that they are not propagated live to the rest of
7009 the function. This can only happen with functions that drop
7010 through; if there had been a return statement, there would
7011 have either been a return rtx, or a jump to the return label.
7013 We delay actual code generation after the current_function_value_rtx
7015 clobber_after = get_last_insn ();
7017 /* Output the label for the actual return from the function,
7018 if one is expected. This happens either because a function epilogue
7019 is used instead of a return instruction, or because a return was done
7020 with a goto in order to run local cleanups, or because of pcc-style
7021 structure returning. */
7023 emit_label (return_label);
7025 /* C++ uses this. */
7027 expand_end_bindings (0, 0, 0);
7029 if (current_function_instrument_entry_exit)
7031 rtx fun = DECL_RTL (current_function_decl);
7032 if (GET_CODE (fun) == MEM)
7033 fun = XEXP (fun, 0);
7036 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode,
7038 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
7040 hard_frame_pointer_rtx),
7044 /* Let except.c know where it should emit the call to unregister
7045 the function context for sjlj exceptions. */
7046 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
7047 sjlj_emit_function_exit_after (get_last_insn ());
7049 /* If we had calls to alloca, and this machine needs
7050 an accurate stack pointer to exit the function,
7051 insert some code to save and restore the stack pointer. */
7052 #ifdef EXIT_IGNORE_STACK
7053 if (! EXIT_IGNORE_STACK)
7055 if (current_function_calls_alloca)
7059 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
7060 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
7063 /* If scalar return value was computed in a pseudo-reg, or was a named
7064 return value that got dumped to the stack, copy that to the hard
7066 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
7068 tree decl_result = DECL_RESULT (current_function_decl);
7069 rtx decl_rtl = DECL_RTL (decl_result);
7071 if (REG_P (decl_rtl)
7072 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
7073 : DECL_REGISTER (decl_result))
7075 rtx real_decl_rtl = current_function_return_rtx;
7077 /* This should be set in assign_parms. */
7078 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
7081 /* If this is a BLKmode structure being returned in registers,
7082 then use the mode computed in expand_return. Note that if
7083 decl_rtl is memory, then its mode may have been changed,
7084 but that current_function_return_rtx has not. */
7085 if (GET_MODE (real_decl_rtl) == BLKmode)
7086 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
7088 /* If a named return value dumped decl_return to memory, then
7089 we may need to re-do the PROMOTE_MODE signed/unsigned
7091 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
7093 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
7095 #ifdef PROMOTE_FUNCTION_RETURN
7096 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
7100 convert_move (real_decl_rtl, decl_rtl, unsignedp);
7102 else if (GET_CODE (real_decl_rtl) == PARALLEL)
7104 /* If expand_function_start has created a PARALLEL for decl_rtl,
7105 move the result to the real return registers. Otherwise, do
7106 a group load from decl_rtl for a named return. */
7107 if (GET_CODE (decl_rtl) == PARALLEL)
7108 emit_group_move (real_decl_rtl, decl_rtl);
7110 emit_group_load (real_decl_rtl, decl_rtl,
7111 int_size_in_bytes (TREE_TYPE (decl_result)));
7114 emit_move_insn (real_decl_rtl, decl_rtl);
7118 /* If returning a structure, arrange to return the address of the value
7119 in a place where debuggers expect to find it.
7121 If returning a structure PCC style,
7122 the caller also depends on this value.
7123 And current_function_returns_pcc_struct is not necessarily set. */
7124 if (current_function_returns_struct
7125 || current_function_returns_pcc_struct)
7128 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
7129 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
7130 #ifdef FUNCTION_OUTGOING_VALUE
7132 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
7133 current_function_decl);
7136 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
7139 /* Mark this as a function return value so integrate will delete the
7140 assignment and USE below when inlining this function. */
7141 REG_FUNCTION_VALUE_P (outgoing) = 1;
7143 #ifdef POINTERS_EXTEND_UNSIGNED
7144 /* The address may be ptr_mode and OUTGOING may be Pmode. */
7145 if (GET_MODE (outgoing) != GET_MODE (value_address))
7146 value_address = convert_memory_address (GET_MODE (outgoing),
7150 emit_move_insn (outgoing, value_address);
7152 /* Show return register used to hold result (in this case the address
7154 current_function_return_rtx = outgoing;
7157 /* If this is an implementation of throw, do what's necessary to
7158 communicate between __builtin_eh_return and the epilogue. */
7159 expand_eh_return ();
7161 /* Emit the actual code to clobber return register. */
7166 clobber_return_register ();
7170 after = emit_insn_after (seq, clobber_after);
7172 if (clobber_after != after)
7173 cfun->x_clobber_return_insn = after;
7176 /* ??? This should no longer be necessary since stupid is no longer with
7177 us, but there are some parts of the compiler (eg reload_combine, and
7178 sh mach_dep_reorg) that still try and compute their own lifetime info
7179 instead of using the general framework. */
7180 use_return_register ();
7182 /* Fix up any gotos that jumped out to the outermost
7183 binding level of the function.
7184 Must follow emitting RETURN_LABEL. */
7186 /* If you have any cleanups to do at this point,
7187 and they need to create temporary variables,
7188 then you will lose. */
7189 expand_fixups (get_insns ());
7193 get_arg_pointer_save_area (f)
7196 rtx ret = f->x_arg_pointer_save_area;
7200 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
7201 f->x_arg_pointer_save_area = ret;
7204 if (f == cfun && ! f->arg_pointer_save_area_init)
7208 /* Save the arg pointer at the beginning of the function. The
7209 generated stack slot may not be a valid memory address, so we
7210 have to check it and fix it if necessary. */
7212 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
7216 push_topmost_sequence ();
7217 emit_insn_after (seq, get_insns ());
7218 pop_topmost_sequence ();
7224 /* Extend a vector that records the INSN_UIDs of INSNS
7225 (a list of one or more insns). */
7228 record_insns (insns, vecp)
7237 while (tmp != NULL_RTX)
7240 tmp = NEXT_INSN (tmp);
7243 i = VARRAY_SIZE (*vecp);
7244 VARRAY_GROW (*vecp, i + len);
7246 while (tmp != NULL_RTX)
7248 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
7250 tmp = NEXT_INSN (tmp);
7254 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
7255 be running after reorg, SEQUENCE rtl is possible. */
7258 contains (insn, vec)
7264 if (GET_CODE (insn) == INSN
7265 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7268 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7269 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7270 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7276 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7277 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7284 prologue_epilogue_contains (insn)
7287 if (contains (insn, prologue))
7289 if (contains (insn, epilogue))
7295 sibcall_epilogue_contains (insn)
7298 if (sibcall_epilogue)
7299 return contains (insn, sibcall_epilogue);
7304 /* Insert gen_return at the end of block BB. This also means updating
7305 block_for_insn appropriately. */
7308 emit_return_into_block (bb, line_note)
7312 emit_jump_insn_after (gen_return (), bb->end);
7314 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
7315 NOTE_LINE_NUMBER (line_note), PREV_INSN (bb->end));
7317 #endif /* HAVE_return */
7319 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7321 /* These functions convert the epilogue into a variant that does not modify the
7322 stack pointer. This is used in cases where a function returns an object
7323 whose size is not known until it is computed. The called function leaves the
7324 object on the stack, leaves the stack depressed, and returns a pointer to
7327 What we need to do is track all modifications and references to the stack
7328 pointer, deleting the modifications and changing the references to point to
7329 the location the stack pointer would have pointed to had the modifications
7332 These functions need to be portable so we need to make as few assumptions
7333 about the epilogue as we can. However, the epilogue basically contains
7334 three things: instructions to reset the stack pointer, instructions to
7335 reload registers, possibly including the frame pointer, and an
7336 instruction to return to the caller.
7338 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7339 We also make no attempt to validate the insns we make since if they are
7340 invalid, we probably can't do anything valid. The intent is that these
7341 routines get "smarter" as more and more machines start to use them and
7342 they try operating on different epilogues.
7344 We use the following structure to track what the part of the epilogue that
7345 we've already processed has done. We keep two copies of the SP equivalence,
7346 one for use during the insn we are processing and one for use in the next
7347 insn. The difference is because one part of a PARALLEL may adjust SP
7348 and the other may use it. */
7352 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7353 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7354 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7355 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7356 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7357 should be set to once we no longer need
7361 static void handle_epilogue_set PARAMS ((rtx, struct epi_info *));
7362 static void emit_equiv_load PARAMS ((struct epi_info *));
7364 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
7365 no modifications to the stack pointer. Return the new list of insns. */
7368 keep_stack_depressed (insns)
7372 struct epi_info info;
7375 /* If the epilogue is just a single instruction, it ust be OK as is. */
7377 if (NEXT_INSN (insns) == NULL_RTX)
7380 /* Otherwise, start a sequence, initialize the information we have, and
7381 process all the insns we were given. */
7384 info.sp_equiv_reg = stack_pointer_rtx;
7386 info.equiv_reg_src = 0;
7390 while (insn != NULL_RTX)
7392 next = NEXT_INSN (insn);
7401 /* If this insn references the register that SP is equivalent to and
7402 we have a pending load to that register, we must force out the load
7403 first and then indicate we no longer know what SP's equivalent is. */
7404 if (info.equiv_reg_src != 0
7405 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7407 emit_equiv_load (&info);
7408 info.sp_equiv_reg = 0;
7411 info.new_sp_equiv_reg = info.sp_equiv_reg;
7412 info.new_sp_offset = info.sp_offset;
7414 /* If this is a (RETURN) and the return address is on the stack,
7415 update the address and change to an indirect jump. */
7416 if (GET_CODE (PATTERN (insn)) == RETURN
7417 || (GET_CODE (PATTERN (insn)) == PARALLEL
7418 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7420 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7422 HOST_WIDE_INT offset = 0;
7423 rtx jump_insn, jump_set;
7425 /* If the return address is in a register, we can emit the insn
7426 unchanged. Otherwise, it must be a MEM and we see what the
7427 base register and offset are. In any case, we have to emit any
7428 pending load to the equivalent reg of SP, if any. */
7429 if (GET_CODE (retaddr) == REG)
7431 emit_equiv_load (&info);
7436 else if (GET_CODE (retaddr) == MEM
7437 && GET_CODE (XEXP (retaddr, 0)) == REG)
7438 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7439 else if (GET_CODE (retaddr) == MEM
7440 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7441 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7442 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7444 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7445 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7450 /* If the base of the location containing the return pointer
7451 is SP, we must update it with the replacement address. Otherwise,
7452 just build the necessary MEM. */
7453 retaddr = plus_constant (base, offset);
7454 if (base == stack_pointer_rtx)
7455 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7456 plus_constant (info.sp_equiv_reg,
7459 retaddr = gen_rtx_MEM (Pmode, retaddr);
7461 /* If there is a pending load to the equivalent register for SP
7462 and we reference that register, we must load our address into
7463 a scratch register and then do that load. */
7464 if (info.equiv_reg_src
7465 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7470 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7471 if (HARD_REGNO_MODE_OK (regno, Pmode)
7472 && !fixed_regs[regno]
7473 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7474 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7476 && !refers_to_regno_p (regno,
7477 regno + HARD_REGNO_NREGS (regno,
7479 info.equiv_reg_src, NULL))
7482 if (regno == FIRST_PSEUDO_REGISTER)
7485 reg = gen_rtx_REG (Pmode, regno);
7486 emit_move_insn (reg, retaddr);
7490 emit_equiv_load (&info);
7491 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7493 /* Show the SET in the above insn is a RETURN. */
7494 jump_set = single_set (jump_insn);
7498 SET_IS_RETURN_P (jump_set) = 1;
7501 /* If SP is not mentioned in the pattern and its equivalent register, if
7502 any, is not modified, just emit it. Otherwise, if neither is set,
7503 replace the reference to SP and emit the insn. If none of those are
7504 true, handle each SET individually. */
7505 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7506 && (info.sp_equiv_reg == stack_pointer_rtx
7507 || !reg_set_p (info.sp_equiv_reg, insn)))
7509 else if (! reg_set_p (stack_pointer_rtx, insn)
7510 && (info.sp_equiv_reg == stack_pointer_rtx
7511 || !reg_set_p (info.sp_equiv_reg, insn)))
7513 if (! validate_replace_rtx (stack_pointer_rtx,
7514 plus_constant (info.sp_equiv_reg,
7521 else if (GET_CODE (PATTERN (insn)) == SET)
7522 handle_epilogue_set (PATTERN (insn), &info);
7523 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7525 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7526 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7527 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7532 info.sp_equiv_reg = info.new_sp_equiv_reg;
7533 info.sp_offset = info.new_sp_offset;
7538 insns = get_insns ();
7543 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7544 structure that contains information about what we've seen so far. We
7545 process this SET by either updating that data or by emitting one or
7549 handle_epilogue_set (set, p)
7553 /* First handle the case where we are setting SP. Record what it is being
7554 set from. If unknown, abort. */
7555 if (reg_set_p (stack_pointer_rtx, set))
7557 if (SET_DEST (set) != stack_pointer_rtx)
7560 if (GET_CODE (SET_SRC (set)) == PLUS
7561 && GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7563 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7564 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7567 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7569 /* If we are adjusting SP, we adjust from the old data. */
7570 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7572 p->new_sp_equiv_reg = p->sp_equiv_reg;
7573 p->new_sp_offset += p->sp_offset;
7576 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7582 /* Next handle the case where we are setting SP's equivalent register.
7583 If we already have a value to set it to, abort. We could update, but
7584 there seems little point in handling that case. Note that we have
7585 to allow for the case where we are setting the register set in
7586 the previous part of a PARALLEL inside a single insn. But use the
7587 old offset for any updates within this insn. */
7588 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7590 if (!rtx_equal_p (p->new_sp_equiv_reg, SET_DEST (set))
7591 || p->equiv_reg_src != 0)
7595 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7596 plus_constant (p->sp_equiv_reg,
7600 /* Otherwise, replace any references to SP in the insn to its new value
7601 and emit the insn. */
7604 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7605 plus_constant (p->sp_equiv_reg,
7607 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7608 plus_constant (p->sp_equiv_reg,
7614 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7620 if (p->equiv_reg_src != 0)
7621 emit_move_insn (p->sp_equiv_reg, p->equiv_reg_src);
7623 p->equiv_reg_src = 0;
7627 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7628 this into place with notes indicating where the prologue ends and where
7629 the epilogue begins. Update the basic block information when possible. */
7632 thread_prologue_and_epilogue_insns (f)
7633 rtx f ATTRIBUTE_UNUSED;
7637 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7640 #ifdef HAVE_prologue
7641 rtx prologue_end = NULL_RTX;
7643 #if defined (HAVE_epilogue) || defined(HAVE_return)
7644 rtx epilogue_end = NULL_RTX;
7647 #ifdef HAVE_prologue
7651 seq = gen_prologue ();
7654 /* Retain a map of the prologue insns. */
7655 record_insns (seq, &prologue);
7656 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
7661 /* Can't deal with multiple successors of the entry block
7662 at the moment. Function should always have at least one
7664 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7667 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7672 /* If the exit block has no non-fake predecessors, we don't need
7674 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7675 if ((e->flags & EDGE_FAKE) == 0)
7681 if (optimize && HAVE_return)
7683 /* If we're allowed to generate a simple return instruction,
7684 then by definition we don't need a full epilogue. Examine
7685 the block that falls through to EXIT. If it does not
7686 contain any code, examine its predecessors and try to
7687 emit (conditional) return instructions. */
7693 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7694 if (e->flags & EDGE_FALLTHRU)
7700 /* Verify that there are no active instructions in the last block. */
7702 while (label && GET_CODE (label) != CODE_LABEL)
7704 if (active_insn_p (label))
7706 label = PREV_INSN (label);
7709 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7711 rtx epilogue_line_note = NULL_RTX;
7713 /* Locate the line number associated with the closing brace,
7714 if we can find one. */
7715 for (seq = get_last_insn ();
7716 seq && ! active_insn_p (seq);
7717 seq = PREV_INSN (seq))
7718 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7720 epilogue_line_note = seq;
7724 for (e = last->pred; e; e = e_next)
7726 basic_block bb = e->src;
7729 e_next = e->pred_next;
7730 if (bb == ENTRY_BLOCK_PTR)
7734 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7737 /* If we have an unconditional jump, we can replace that
7738 with a simple return instruction. */
7739 if (simplejump_p (jump))
7741 emit_return_into_block (bb, epilogue_line_note);
7745 /* If we have a conditional jump, we can try to replace
7746 that with a conditional return instruction. */
7747 else if (condjump_p (jump))
7749 if (! redirect_jump (jump, 0, 0))
7752 /* If this block has only one successor, it both jumps
7753 and falls through to the fallthru block, so we can't
7755 if (bb->succ->succ_next == NULL)
7761 /* Fix up the CFG for the successful change we just made. */
7762 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7765 /* Emit a return insn for the exit fallthru block. Whether
7766 this is still reachable will be determined later. */
7768 emit_barrier_after (last->end);
7769 emit_return_into_block (last, epilogue_line_note);
7770 epilogue_end = last->end;
7771 last->succ->flags &= ~EDGE_FALLTHRU;
7776 #ifdef HAVE_epilogue
7779 /* Find the edge that falls through to EXIT. Other edges may exist
7780 due to RETURN instructions, but those don't need epilogues.
7781 There really shouldn't be a mixture -- either all should have
7782 been converted or none, however... */
7784 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7785 if (e->flags & EDGE_FALLTHRU)
7791 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
7793 seq = gen_epilogue ();
7795 #ifdef INCOMING_RETURN_ADDR_RTX
7796 /* If this function returns with the stack depressed and we can support
7797 it, massage the epilogue to actually do that. */
7798 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7799 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7800 seq = keep_stack_depressed (seq);
7803 emit_jump_insn (seq);
7805 /* Retain a map of the epilogue insns. */
7806 record_insns (seq, &epilogue);
7811 insert_insn_on_edge (seq, e);
7818 commit_edge_insertions ();
7820 #ifdef HAVE_sibcall_epilogue
7821 /* Emit sibling epilogues before any sibling call sites. */
7822 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7824 basic_block bb = e->src;
7829 if (GET_CODE (insn) != CALL_INSN
7830 || ! SIBLING_CALL_P (insn))
7834 emit_insn (gen_sibcall_epilogue ());
7838 /* Retain a map of the epilogue insns. Used in life analysis to
7839 avoid getting rid of sibcall epilogue insns. Do this before we
7840 actually emit the sequence. */
7841 record_insns (seq, &sibcall_epilogue);
7843 i = PREV_INSN (insn);
7844 newinsn = emit_insn_before (seq, insn);
7848 #ifdef HAVE_prologue
7853 /* GDB handles `break f' by setting a breakpoint on the first
7854 line note after the prologue. Which means (1) that if
7855 there are line number notes before where we inserted the
7856 prologue we should move them, and (2) we should generate a
7857 note before the end of the first basic block, if there isn't
7860 ??? This behavior is completely broken when dealing with
7861 multiple entry functions. We simply place the note always
7862 into first basic block and let alternate entry points
7866 for (insn = prologue_end; insn; insn = prev)
7868 prev = PREV_INSN (insn);
7869 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7871 /* Note that we cannot reorder the first insn in the
7872 chain, since rest_of_compilation relies on that
7873 remaining constant. */
7876 reorder_insns (insn, insn, prologue_end);
7880 /* Find the last line number note in the first block. */
7881 for (insn = ENTRY_BLOCK_PTR->next_bb->end;
7882 insn != prologue_end && insn;
7883 insn = PREV_INSN (insn))
7884 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7887 /* If we didn't find one, make a copy of the first line number
7891 for (insn = next_active_insn (prologue_end);
7893 insn = PREV_INSN (insn))
7894 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7896 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7897 NOTE_LINE_NUMBER (insn),
7904 #ifdef HAVE_epilogue
7909 /* Similarly, move any line notes that appear after the epilogue.
7910 There is no need, however, to be quite so anal about the existence
7912 for (insn = epilogue_end; insn; insn = next)
7914 next = NEXT_INSN (insn);
7915 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7916 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7922 /* Reposition the prologue-end and epilogue-begin notes after instruction
7923 scheduling and delayed branch scheduling. */
7926 reposition_prologue_and_epilogue_notes (f)
7927 rtx f ATTRIBUTE_UNUSED;
7929 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7930 rtx insn, last, note;
7933 if ((len = VARRAY_SIZE (prologue)) > 0)
7937 /* Scan from the beginning until we reach the last prologue insn.
7938 We apparently can't depend on basic_block_{head,end} after
7940 for (insn = f; insn; insn = NEXT_INSN (insn))
7942 if (GET_CODE (insn) == NOTE)
7944 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7947 else if (contains (insn, prologue))
7957 /* Find the prologue-end note if we haven't already, and
7958 move it to just after the last prologue insn. */
7961 for (note = last; (note = NEXT_INSN (note));)
7962 if (GET_CODE (note) == NOTE
7963 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7967 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7968 if (GET_CODE (last) == CODE_LABEL)
7969 last = NEXT_INSN (last);
7970 reorder_insns (note, note, last);
7974 if ((len = VARRAY_SIZE (epilogue)) > 0)
7978 /* Scan from the end until we reach the first epilogue insn.
7979 We apparently can't depend on basic_block_{head,end} after
7981 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
7983 if (GET_CODE (insn) == NOTE)
7985 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7988 else if (contains (insn, epilogue))
7998 /* Find the epilogue-begin note if we haven't already, and
7999 move it to just before the first epilogue insn. */
8002 for (note = insn; (note = PREV_INSN (note));)
8003 if (GET_CODE (note) == NOTE
8004 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
8008 if (PREV_INSN (last) != note)
8009 reorder_insns (note, note, PREV_INSN (last));
8012 #endif /* HAVE_prologue or HAVE_epilogue */
8015 /* Called once, at initialization, to initialize function.c. */
8018 init_function_once ()
8020 VARRAY_INT_INIT (prologue, 0, "prologue");
8021 VARRAY_INT_INIT (epilogue, 0, "epilogue");
8022 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
8025 #include "gt-function.h"