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)
4345 CUMULATIVE_ARGS args_so_far;
4346 enum machine_mode promoted_mode, passed_mode;
4347 enum machine_mode nominal_mode, promoted_nominal_mode;
4349 /* Total space needed so far for args on the stack,
4350 given as a constant and a tree-expression. */
4351 struct args_size stack_args_size;
4352 tree fntype = TREE_TYPE (fndecl);
4353 tree fnargs = DECL_ARGUMENTS (fndecl);
4354 /* This is used for the arg pointer when referring to stack args. */
4355 rtx internal_arg_pointer;
4356 /* This is a dummy PARM_DECL that we used for the function result if
4357 the function returns a structure. */
4358 tree function_result_decl = 0;
4359 #ifdef SETUP_INCOMING_VARARGS
4360 int varargs_setup = 0;
4362 rtx conversion_insns = 0;
4363 struct args_size alignment_pad;
4365 /* Nonzero if function takes extra anonymous args.
4366 This means the last named arg must be on the stack
4367 right before the anonymous ones. */
4369 = (TYPE_ARG_TYPES (fntype) != 0
4370 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4371 != void_type_node));
4373 current_function_stdarg = stdarg;
4375 /* If the reg that the virtual arg pointer will be translated into is
4376 not a fixed reg or is the stack pointer, make a copy of the virtual
4377 arg pointer, and address parms via the copy. The frame pointer is
4378 considered fixed even though it is not marked as such.
4380 The second time through, simply use ap to avoid generating rtx. */
4382 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4383 || ! (fixed_regs[ARG_POINTER_REGNUM]
4384 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4385 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4387 internal_arg_pointer = virtual_incoming_args_rtx;
4388 current_function_internal_arg_pointer = internal_arg_pointer;
4390 stack_args_size.constant = 0;
4391 stack_args_size.var = 0;
4393 /* If struct value address is treated as the first argument, make it so. */
4394 if (aggregate_value_p (DECL_RESULT (fndecl))
4395 && ! current_function_returns_pcc_struct
4396 && struct_value_incoming_rtx == 0)
4398 tree type = build_pointer_type (TREE_TYPE (fntype));
4400 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4402 DECL_ARG_TYPE (function_result_decl) = type;
4403 TREE_CHAIN (function_result_decl) = fnargs;
4404 fnargs = function_result_decl;
4407 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4408 parm_reg_stack_loc = (rtx *) ggc_alloc_cleared (max_parm_reg * sizeof (rtx));
4410 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4411 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4413 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, fndecl);
4416 /* We haven't yet found an argument that we must push and pretend the
4418 current_function_pretend_args_size = 0;
4420 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4422 struct args_size stack_offset;
4423 struct args_size arg_size;
4424 int passed_pointer = 0;
4425 int did_conversion = 0;
4426 tree passed_type = DECL_ARG_TYPE (parm);
4427 tree nominal_type = TREE_TYPE (parm);
4429 int last_named = 0, named_arg;
4431 /* Set LAST_NAMED if this is last named arg before last
4437 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4438 if (DECL_NAME (tem))
4444 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4445 most machines, if this is a varargs/stdarg function, then we treat
4446 the last named arg as if it were anonymous too. */
4447 named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4449 if (TREE_TYPE (parm) == error_mark_node
4450 /* This can happen after weird syntax errors
4451 or if an enum type is defined among the parms. */
4452 || TREE_CODE (parm) != PARM_DECL
4453 || passed_type == NULL)
4455 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4456 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4457 TREE_USED (parm) = 1;
4461 /* Find mode of arg as it is passed, and mode of arg
4462 as it should be during execution of this function. */
4463 passed_mode = TYPE_MODE (passed_type);
4464 nominal_mode = TYPE_MODE (nominal_type);
4466 /* If the parm's mode is VOID, its value doesn't matter,
4467 and avoid the usual things like emit_move_insn that could crash. */
4468 if (nominal_mode == VOIDmode)
4470 SET_DECL_RTL (parm, const0_rtx);
4471 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4475 /* If the parm is to be passed as a transparent union, use the
4476 type of the first field for the tests below. We have already
4477 verified that the modes are the same. */
4478 if (DECL_TRANSPARENT_UNION (parm)
4479 || (TREE_CODE (passed_type) == UNION_TYPE
4480 && TYPE_TRANSPARENT_UNION (passed_type)))
4481 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4483 /* See if this arg was passed by invisible reference. It is if
4484 it is an object whose size depends on the contents of the
4485 object itself or if the machine requires these objects be passed
4488 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4489 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4490 || TREE_ADDRESSABLE (passed_type)
4491 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4492 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4493 passed_type, named_arg)
4497 passed_type = nominal_type = build_pointer_type (passed_type);
4499 passed_mode = nominal_mode = Pmode;
4501 /* See if the frontend wants to pass this by invisible reference. */
4502 else if (passed_type != nominal_type
4503 && POINTER_TYPE_P (passed_type)
4504 && TREE_TYPE (passed_type) == nominal_type)
4506 nominal_type = passed_type;
4508 passed_mode = nominal_mode = Pmode;
4511 promoted_mode = passed_mode;
4513 #ifdef PROMOTE_FUNCTION_ARGS
4514 /* Compute the mode in which the arg is actually extended to. */
4515 unsignedp = TREE_UNSIGNED (passed_type);
4516 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4519 /* Let machine desc say which reg (if any) the parm arrives in.
4520 0 means it arrives on the stack. */
4521 #ifdef FUNCTION_INCOMING_ARG
4522 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4523 passed_type, named_arg);
4525 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4526 passed_type, named_arg);
4529 if (entry_parm == 0)
4530 promoted_mode = passed_mode;
4532 #ifdef SETUP_INCOMING_VARARGS
4533 /* If this is the last named parameter, do any required setup for
4534 varargs or stdargs. We need to know about the case of this being an
4535 addressable type, in which case we skip the registers it
4536 would have arrived in.
4538 For stdargs, LAST_NAMED will be set for two parameters, the one that
4539 is actually the last named, and the dummy parameter. We only
4540 want to do this action once.
4542 Also, indicate when RTL generation is to be suppressed. */
4543 if (last_named && !varargs_setup)
4545 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4546 current_function_pretend_args_size, 0);
4551 /* Determine parm's home in the stack,
4552 in case it arrives in the stack or we should pretend it did.
4554 Compute the stack position and rtx where the argument arrives
4557 There is one complexity here: If this was a parameter that would
4558 have been passed in registers, but wasn't only because it is
4559 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4560 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4561 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4562 0 as it was the previous time. */
4564 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4565 locate_and_pad_parm (promoted_mode, passed_type,
4566 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4569 #ifdef FUNCTION_INCOMING_ARG
4570 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4572 pretend_named) != 0,
4574 FUNCTION_ARG (args_so_far, promoted_mode,
4576 pretend_named) != 0,
4579 fndecl, &stack_args_size, &stack_offset, &arg_size,
4583 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4585 if (offset_rtx == const0_rtx)
4586 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4588 stack_parm = gen_rtx_MEM (promoted_mode,
4589 gen_rtx_PLUS (Pmode,
4590 internal_arg_pointer,
4593 set_mem_attributes (stack_parm, parm, 1);
4595 /* Set also REG_ATTRS if parameter was passed in a register. */
4597 set_reg_attrs_for_parm (entry_parm, stack_parm);
4600 /* If this parameter was passed both in registers and in the stack,
4601 use the copy on the stack. */
4602 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4605 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4606 /* If this parm was passed part in regs and part in memory,
4607 pretend it arrived entirely in memory
4608 by pushing the register-part onto the stack.
4610 In the special case of a DImode or DFmode that is split,
4611 we could put it together in a pseudoreg directly,
4612 but for now that's not worth bothering with. */
4616 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4617 passed_type, named_arg);
4621 #if defined (REG_PARM_STACK_SPACE) && !defined (MAYBE_REG_PARM_STACK_SPACE)
4622 /* When REG_PARM_STACK_SPACE is nonzero, stack space for
4623 split parameters was allocated by our caller, so we
4624 won't be pushing it in the prolog. */
4625 if (REG_PARM_STACK_SPACE (fndecl) == 0)
4627 current_function_pretend_args_size
4628 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4629 / (PARM_BOUNDARY / BITS_PER_UNIT)
4630 * (PARM_BOUNDARY / BITS_PER_UNIT));
4632 /* Handle calls that pass values in multiple non-contiguous
4633 locations. The Irix 6 ABI has examples of this. */
4634 if (GET_CODE (entry_parm) == PARALLEL)
4635 emit_group_store (validize_mem (stack_parm), entry_parm,
4636 int_size_in_bytes (TREE_TYPE (parm)));
4639 move_block_from_reg (REGNO (entry_parm),
4640 validize_mem (stack_parm), nregs,
4641 int_size_in_bytes (TREE_TYPE (parm)));
4643 entry_parm = stack_parm;
4648 /* If we didn't decide this parm came in a register,
4649 by default it came on the stack. */
4650 if (entry_parm == 0)
4651 entry_parm = stack_parm;
4653 /* Record permanently how this parm was passed. */
4654 DECL_INCOMING_RTL (parm) = entry_parm;
4656 /* If there is actually space on the stack for this parm,
4657 count it in stack_args_size; otherwise set stack_parm to 0
4658 to indicate there is no preallocated stack slot for the parm. */
4660 if (entry_parm == stack_parm
4661 || (GET_CODE (entry_parm) == PARALLEL
4662 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4663 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4664 /* On some machines, even if a parm value arrives in a register
4665 there is still an (uninitialized) stack slot allocated for it.
4667 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4668 whether this parameter already has a stack slot allocated,
4669 because an arg block exists only if current_function_args_size
4670 is larger than some threshold, and we haven't calculated that
4671 yet. So, for now, we just assume that stack slots never exist
4673 || REG_PARM_STACK_SPACE (fndecl) > 0
4677 stack_args_size.constant += arg_size.constant;
4679 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4682 /* No stack slot was pushed for this parm. */
4685 /* Update info on where next arg arrives in registers. */
4687 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4688 passed_type, named_arg);
4690 /* If we can't trust the parm stack slot to be aligned enough
4691 for its ultimate type, don't use that slot after entry.
4692 We'll make another stack slot, if we need one. */
4694 unsigned int thisparm_boundary
4695 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4697 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4701 /* If parm was passed in memory, and we need to convert it on entry,
4702 don't store it back in that same slot. */
4704 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4707 /* When an argument is passed in multiple locations, we can't
4708 make use of this information, but we can save some copying if
4709 the whole argument is passed in a single register. */
4710 if (GET_CODE (entry_parm) == PARALLEL
4711 && nominal_mode != BLKmode && passed_mode != BLKmode)
4713 int i, len = XVECLEN (entry_parm, 0);
4715 for (i = 0; i < len; i++)
4716 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4717 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4718 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4720 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4722 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4723 DECL_INCOMING_RTL (parm) = entry_parm;
4728 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4729 in the mode in which it arrives.
4730 STACK_PARM is an RTX for a stack slot where the parameter can live
4731 during the function (in case we want to put it there).
4732 STACK_PARM is 0 if no stack slot was pushed for it.
4734 Now output code if necessary to convert ENTRY_PARM to
4735 the type in which this function declares it,
4736 and store that result in an appropriate place,
4737 which may be a pseudo reg, may be STACK_PARM,
4738 or may be a local stack slot if STACK_PARM is 0.
4740 Set DECL_RTL to that place. */
4742 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4744 /* If a BLKmode arrives in registers, copy it to a stack slot.
4745 Handle calls that pass values in multiple non-contiguous
4746 locations. The Irix 6 ABI has examples of this. */
4747 if (GET_CODE (entry_parm) == REG
4748 || GET_CODE (entry_parm) == PARALLEL)
4751 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4754 /* Note that we will be storing an integral number of words.
4755 So we have to be careful to ensure that we allocate an
4756 integral number of words. We do this below in the
4757 assign_stack_local if space was not allocated in the argument
4758 list. If it was, this will not work if PARM_BOUNDARY is not
4759 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4760 if it becomes a problem. */
4762 if (stack_parm == 0)
4765 = assign_stack_local (GET_MODE (entry_parm),
4767 set_mem_attributes (stack_parm, parm, 1);
4770 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4773 /* Handle calls that pass values in multiple non-contiguous
4774 locations. The Irix 6 ABI has examples of this. */
4775 if (GET_CODE (entry_parm) == PARALLEL)
4776 emit_group_store (validize_mem (stack_parm), entry_parm,
4777 int_size_in_bytes (TREE_TYPE (parm)));
4779 move_block_from_reg (REGNO (entry_parm),
4780 validize_mem (stack_parm),
4781 size_stored / UNITS_PER_WORD,
4782 int_size_in_bytes (TREE_TYPE (parm)));
4784 SET_DECL_RTL (parm, stack_parm);
4786 else if (! ((! optimize
4787 && ! DECL_REGISTER (parm))
4788 || TREE_SIDE_EFFECTS (parm)
4789 /* If -ffloat-store specified, don't put explicit
4790 float variables into registers. */
4791 || (flag_float_store
4792 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4793 /* Always assign pseudo to structure return or item passed
4794 by invisible reference. */
4795 || passed_pointer || parm == function_result_decl)
4797 /* Store the parm in a pseudoregister during the function, but we
4798 may need to do it in a wider mode. */
4801 unsigned int regno, regnoi = 0, regnor = 0;
4803 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4805 promoted_nominal_mode
4806 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4808 parmreg = gen_reg_rtx (promoted_nominal_mode);
4809 mark_user_reg (parmreg);
4811 /* If this was an item that we received a pointer to, set DECL_RTL
4815 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4817 set_mem_attributes (x, parm, 1);
4818 SET_DECL_RTL (parm, x);
4822 SET_DECL_RTL (parm, parmreg);
4823 maybe_set_unchanging (DECL_RTL (parm), parm);
4826 /* Copy the value into the register. */
4827 if (nominal_mode != passed_mode
4828 || promoted_nominal_mode != promoted_mode)
4831 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4832 mode, by the caller. We now have to convert it to
4833 NOMINAL_MODE, if different. However, PARMREG may be in
4834 a different mode than NOMINAL_MODE if it is being stored
4837 If ENTRY_PARM is a hard register, it might be in a register
4838 not valid for operating in its mode (e.g., an odd-numbered
4839 register for a DFmode). In that case, moves are the only
4840 thing valid, so we can't do a convert from there. This
4841 occurs when the calling sequence allow such misaligned
4844 In addition, the conversion may involve a call, which could
4845 clobber parameters which haven't been copied to pseudo
4846 registers yet. Therefore, we must first copy the parm to
4847 a pseudo reg here, and save the conversion until after all
4848 parameters have been moved. */
4850 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4852 emit_move_insn (tempreg, validize_mem (entry_parm));
4854 push_to_sequence (conversion_insns);
4855 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4857 if (GET_CODE (tempreg) == SUBREG
4858 && GET_MODE (tempreg) == nominal_mode
4859 && GET_CODE (SUBREG_REG (tempreg)) == REG
4860 && nominal_mode == passed_mode
4861 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4862 && GET_MODE_SIZE (GET_MODE (tempreg))
4863 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4865 /* The argument is already sign/zero extended, so note it
4867 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4868 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4871 /* TREE_USED gets set erroneously during expand_assignment. */
4872 save_tree_used = TREE_USED (parm);
4873 expand_assignment (parm,
4874 make_tree (nominal_type, tempreg), 0, 0);
4875 TREE_USED (parm) = save_tree_used;
4876 conversion_insns = get_insns ();
4881 emit_move_insn (parmreg, validize_mem (entry_parm));
4883 /* If we were passed a pointer but the actual value
4884 can safely live in a register, put it in one. */
4885 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4886 /* If by-reference argument was promoted, demote it. */
4887 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4889 && ! DECL_REGISTER (parm))
4890 || TREE_SIDE_EFFECTS (parm)
4891 /* If -ffloat-store specified, don't put explicit
4892 float variables into registers. */
4893 || (flag_float_store
4894 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4896 /* We can't use nominal_mode, because it will have been set to
4897 Pmode above. We must use the actual mode of the parm. */
4898 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4899 mark_user_reg (parmreg);
4900 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4902 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4903 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4904 push_to_sequence (conversion_insns);
4905 emit_move_insn (tempreg, DECL_RTL (parm));
4907 convert_to_mode (GET_MODE (parmreg),
4910 emit_move_insn (parmreg, DECL_RTL (parm));
4911 conversion_insns = get_insns();
4916 emit_move_insn (parmreg, DECL_RTL (parm));
4917 SET_DECL_RTL (parm, parmreg);
4918 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4922 #ifdef FUNCTION_ARG_CALLEE_COPIES
4923 /* If we are passed an arg by reference and it is our responsibility
4924 to make a copy, do it now.
4925 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4926 original argument, so we must recreate them in the call to
4927 FUNCTION_ARG_CALLEE_COPIES. */
4928 /* ??? Later add code to handle the case that if the argument isn't
4929 modified, don't do the copy. */
4931 else if (passed_pointer
4932 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4933 TYPE_MODE (DECL_ARG_TYPE (parm)),
4934 DECL_ARG_TYPE (parm),
4936 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4939 tree type = DECL_ARG_TYPE (parm);
4941 /* This sequence may involve a library call perhaps clobbering
4942 registers that haven't been copied to pseudos yet. */
4944 push_to_sequence (conversion_insns);
4946 if (!COMPLETE_TYPE_P (type)
4947 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4948 /* This is a variable sized object. */
4949 copy = gen_rtx_MEM (BLKmode,
4950 allocate_dynamic_stack_space
4951 (expr_size (parm), NULL_RTX,
4952 TYPE_ALIGN (type)));
4954 copy = assign_stack_temp (TYPE_MODE (type),
4955 int_size_in_bytes (type), 1);
4956 set_mem_attributes (copy, parm, 1);
4958 store_expr (parm, copy, 0);
4959 emit_move_insn (parmreg, XEXP (copy, 0));
4960 conversion_insns = get_insns ();
4964 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4966 /* In any case, record the parm's desired stack location
4967 in case we later discover it must live in the stack.
4969 If it is a COMPLEX value, store the stack location for both
4972 if (GET_CODE (parmreg) == CONCAT)
4973 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4975 regno = REGNO (parmreg);
4977 if (regno >= max_parm_reg)
4980 int old_max_parm_reg = max_parm_reg;
4982 /* It's slow to expand this one register at a time,
4983 but it's also rare and we need max_parm_reg to be
4984 precisely correct. */
4985 max_parm_reg = regno + 1;
4986 new = (rtx *) ggc_realloc (parm_reg_stack_loc,
4987 max_parm_reg * sizeof (rtx));
4988 memset ((char *) (new + old_max_parm_reg), 0,
4989 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4990 parm_reg_stack_loc = new;
4993 if (GET_CODE (parmreg) == CONCAT)
4995 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4997 regnor = REGNO (gen_realpart (submode, parmreg));
4998 regnoi = REGNO (gen_imagpart (submode, parmreg));
5000 if (stack_parm != 0)
5002 parm_reg_stack_loc[regnor]
5003 = gen_realpart (submode, stack_parm);
5004 parm_reg_stack_loc[regnoi]
5005 = gen_imagpart (submode, stack_parm);
5009 parm_reg_stack_loc[regnor] = 0;
5010 parm_reg_stack_loc[regnoi] = 0;
5014 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
5016 /* Mark the register as eliminable if we did no conversion
5017 and it was copied from memory at a fixed offset,
5018 and the arg pointer was not copied to a pseudo-reg.
5019 If the arg pointer is a pseudo reg or the offset formed
5020 an invalid address, such memory-equivalences
5021 as we make here would screw up life analysis for it. */
5022 if (nominal_mode == passed_mode
5025 && GET_CODE (stack_parm) == MEM
5026 && stack_offset.var == 0
5027 && reg_mentioned_p (virtual_incoming_args_rtx,
5028 XEXP (stack_parm, 0)))
5030 rtx linsn = get_last_insn ();
5033 /* Mark complex types separately. */
5034 if (GET_CODE (parmreg) == CONCAT)
5035 /* Scan backwards for the set of the real and
5037 for (sinsn = linsn; sinsn != 0;
5038 sinsn = prev_nonnote_insn (sinsn))
5040 set = single_set (sinsn);
5042 && SET_DEST (set) == regno_reg_rtx [regnoi])
5044 = gen_rtx_EXPR_LIST (REG_EQUIV,
5045 parm_reg_stack_loc[regnoi],
5048 && SET_DEST (set) == regno_reg_rtx [regnor])
5050 = gen_rtx_EXPR_LIST (REG_EQUIV,
5051 parm_reg_stack_loc[regnor],
5054 else if ((set = single_set (linsn)) != 0
5055 && SET_DEST (set) == parmreg)
5057 = gen_rtx_EXPR_LIST (REG_EQUIV,
5058 stack_parm, REG_NOTES (linsn));
5061 /* For pointer data type, suggest pointer register. */
5062 if (POINTER_TYPE_P (TREE_TYPE (parm)))
5063 mark_reg_pointer (parmreg,
5064 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5066 /* If something wants our address, try to use ADDRESSOF. */
5067 if (TREE_ADDRESSABLE (parm))
5069 /* If we end up putting something into the stack,
5070 fixup_var_refs_insns will need to make a pass over
5071 all the instructions. It looks through the pending
5072 sequences -- but it can't see the ones in the
5073 CONVERSION_INSNS, if they're not on the sequence
5074 stack. So, we go back to that sequence, just so that
5075 the fixups will happen. */
5076 push_to_sequence (conversion_insns);
5077 put_var_into_stack (parm, /*rescan=*/true);
5078 conversion_insns = get_insns ();
5084 /* Value must be stored in the stack slot STACK_PARM
5085 during function execution. */
5087 if (promoted_mode != nominal_mode)
5089 /* Conversion is required. */
5090 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
5092 emit_move_insn (tempreg, validize_mem (entry_parm));
5094 push_to_sequence (conversion_insns);
5095 entry_parm = convert_to_mode (nominal_mode, tempreg,
5096 TREE_UNSIGNED (TREE_TYPE (parm)));
5098 /* ??? This may need a big-endian conversion on sparc64. */
5099 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
5101 conversion_insns = get_insns ();
5106 if (entry_parm != stack_parm)
5108 if (stack_parm == 0)
5111 = assign_stack_local (GET_MODE (entry_parm),
5112 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
5113 set_mem_attributes (stack_parm, parm, 1);
5116 if (promoted_mode != nominal_mode)
5118 push_to_sequence (conversion_insns);
5119 emit_move_insn (validize_mem (stack_parm),
5120 validize_mem (entry_parm));
5121 conversion_insns = get_insns ();
5125 emit_move_insn (validize_mem (stack_parm),
5126 validize_mem (entry_parm));
5129 SET_DECL_RTL (parm, stack_parm);
5133 /* Output all parameter conversion instructions (possibly including calls)
5134 now that all parameters have been copied out of hard registers. */
5135 emit_insn (conversion_insns);
5137 /* If we are receiving a struct value address as the first argument, set up
5138 the RTL for the function result. As this might require code to convert
5139 the transmitted address to Pmode, we do this here to ensure that possible
5140 preliminary conversions of the address have been emitted already. */
5141 if (function_result_decl)
5143 tree result = DECL_RESULT (fndecl);
5144 rtx addr = DECL_RTL (function_result_decl);
5147 #ifdef POINTERS_EXTEND_UNSIGNED
5148 if (GET_MODE (addr) != Pmode)
5149 addr = convert_memory_address (Pmode, addr);
5152 x = gen_rtx_MEM (DECL_MODE (result), addr);
5153 set_mem_attributes (x, result, 1);
5154 SET_DECL_RTL (result, x);
5157 last_parm_insn = get_last_insn ();
5159 current_function_args_size = stack_args_size.constant;
5161 /* Adjust function incoming argument size for alignment and
5164 #ifdef REG_PARM_STACK_SPACE
5165 #ifndef MAYBE_REG_PARM_STACK_SPACE
5166 current_function_args_size = MAX (current_function_args_size,
5167 REG_PARM_STACK_SPACE (fndecl));
5171 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
5173 current_function_args_size
5174 = ((current_function_args_size + STACK_BYTES - 1)
5175 / STACK_BYTES) * STACK_BYTES;
5177 #ifdef ARGS_GROW_DOWNWARD
5178 current_function_arg_offset_rtx
5179 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5180 : expand_expr (size_diffop (stack_args_size.var,
5181 size_int (-stack_args_size.constant)),
5182 NULL_RTX, VOIDmode, 0));
5184 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5187 /* See how many bytes, if any, of its args a function should try to pop
5190 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5191 current_function_args_size);
5193 /* For stdarg.h function, save info about
5194 regs and stack space used by the named args. */
5196 current_function_args_info = args_so_far;
5198 /* Set the rtx used for the function return value. Put this in its
5199 own variable so any optimizers that need this information don't have
5200 to include tree.h. Do this here so it gets done when an inlined
5201 function gets output. */
5203 current_function_return_rtx
5204 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5205 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5207 /* If scalar return value was computed in a pseudo-reg, or was a named
5208 return value that got dumped to the stack, copy that to the hard
5210 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5212 tree decl_result = DECL_RESULT (fndecl);
5213 rtx decl_rtl = DECL_RTL (decl_result);
5215 if (REG_P (decl_rtl)
5216 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5217 : DECL_REGISTER (decl_result))
5221 #ifdef FUNCTION_OUTGOING_VALUE
5222 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5225 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5228 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5229 /* The delay slot scheduler assumes that current_function_return_rtx
5230 holds the hard register containing the return value, not a
5231 temporary pseudo. */
5232 current_function_return_rtx = real_decl_rtl;
5237 /* Indicate whether REGNO is an incoming argument to the current function
5238 that was promoted to a wider mode. If so, return the RTX for the
5239 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5240 that REGNO is promoted from and whether the promotion was signed or
5243 #ifdef PROMOTE_FUNCTION_ARGS
5246 promoted_input_arg (regno, pmode, punsignedp)
5248 enum machine_mode *pmode;
5253 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5254 arg = TREE_CHAIN (arg))
5255 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5256 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5257 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5259 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5260 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5262 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5263 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5264 && mode != DECL_MODE (arg))
5266 *pmode = DECL_MODE (arg);
5267 *punsignedp = unsignedp;
5268 return DECL_INCOMING_RTL (arg);
5277 /* Compute the size and offset from the start of the stacked arguments for a
5278 parm passed in mode PASSED_MODE and with type TYPE.
5280 INITIAL_OFFSET_PTR points to the current offset into the stacked
5283 The starting offset and size for this parm are returned in *OFFSET_PTR
5284 and *ARG_SIZE_PTR, respectively.
5286 IN_REGS is nonzero if the argument will be passed in registers. It will
5287 never be set if REG_PARM_STACK_SPACE is not defined.
5289 FNDECL is the function in which the argument was defined.
5291 There are two types of rounding that are done. The first, controlled by
5292 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5293 list to be aligned to the specific boundary (in bits). This rounding
5294 affects the initial and starting offsets, but not the argument size.
5296 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5297 optionally rounds the size of the parm to PARM_BOUNDARY. The
5298 initial offset is not affected by this rounding, while the size always
5299 is and the starting offset may be. */
5301 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
5302 initial_offset_ptr is positive because locate_and_pad_parm's
5303 callers pass in the total size of args so far as
5304 initial_offset_ptr. arg_size_ptr is always positive. */
5307 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
5308 initial_offset_ptr, offset_ptr, arg_size_ptr,
5310 enum machine_mode passed_mode;
5312 int in_regs ATTRIBUTE_UNUSED;
5313 tree fndecl ATTRIBUTE_UNUSED;
5314 struct args_size *initial_offset_ptr;
5315 struct args_size *offset_ptr;
5316 struct args_size *arg_size_ptr;
5317 struct args_size *alignment_pad;
5321 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5322 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5323 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5324 #ifdef ARGS_GROW_DOWNWARD
5328 #ifdef REG_PARM_STACK_SPACE
5329 /* If we have found a stack parm before we reach the end of the
5330 area reserved for registers, skip that area. */
5333 int reg_parm_stack_space = 0;
5335 #ifdef MAYBE_REG_PARM_STACK_SPACE
5336 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5338 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5340 if (reg_parm_stack_space > 0)
5342 if (initial_offset_ptr->var)
5344 initial_offset_ptr->var
5345 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5346 ssize_int (reg_parm_stack_space));
5347 initial_offset_ptr->constant = 0;
5349 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5350 initial_offset_ptr->constant = reg_parm_stack_space;
5353 #endif /* REG_PARM_STACK_SPACE */
5355 arg_size_ptr->var = 0;
5356 arg_size_ptr->constant = 0;
5357 alignment_pad->var = 0;
5358 alignment_pad->constant = 0;
5360 #ifdef ARGS_GROW_DOWNWARD
5361 if (initial_offset_ptr->var)
5363 offset_ptr->constant = 0;
5364 offset_ptr->var = size_binop (MINUS_EXPR, ssize_int (0),
5365 initial_offset_ptr->var);
5369 offset_ptr->constant = -initial_offset_ptr->constant;
5370 offset_ptr->var = 0;
5373 if (where_pad != none
5374 && (!host_integerp (sizetree, 1)
5375 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5376 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
5377 SUB_PARM_SIZE (*offset_ptr, s2);
5380 #ifdef REG_PARM_STACK_SPACE
5381 || REG_PARM_STACK_SPACE (fndecl) > 0
5384 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5386 if (initial_offset_ptr->var)
5387 arg_size_ptr->var = size_binop (MINUS_EXPR,
5388 size_binop (MINUS_EXPR,
5390 initial_offset_ptr->var),
5394 arg_size_ptr->constant = (-initial_offset_ptr->constant
5395 - offset_ptr->constant);
5397 /* Pad_below needs the pre-rounded size to know how much to pad below.
5398 We only pad parameters which are not in registers as they have their
5399 padding done elsewhere. */
5400 if (where_pad == downward
5402 pad_below (offset_ptr, passed_mode, sizetree);
5404 #else /* !ARGS_GROW_DOWNWARD */
5406 #ifdef REG_PARM_STACK_SPACE
5407 || REG_PARM_STACK_SPACE (fndecl) > 0
5410 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5411 *offset_ptr = *initial_offset_ptr;
5413 #ifdef PUSH_ROUNDING
5414 if (passed_mode != BLKmode)
5415 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5418 /* Pad_below needs the pre-rounded size to know how much to pad below
5419 so this must be done before rounding up. */
5420 if (where_pad == downward
5421 /* However, BLKmode args passed in regs have their padding done elsewhere.
5422 The stack slot must be able to hold the entire register. */
5423 && !(in_regs && passed_mode == BLKmode))
5424 pad_below (offset_ptr, passed_mode, sizetree);
5426 if (where_pad != none
5427 && (!host_integerp (sizetree, 1)
5428 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5429 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5431 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5432 #endif /* ARGS_GROW_DOWNWARD */
5435 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5436 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5439 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5440 struct args_size *offset_ptr;
5442 struct args_size *alignment_pad;
5444 tree save_var = NULL_TREE;
5445 HOST_WIDE_INT save_constant = 0;
5447 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5449 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5451 save_var = offset_ptr->var;
5452 save_constant = offset_ptr->constant;
5455 alignment_pad->var = NULL_TREE;
5456 alignment_pad->constant = 0;
5458 if (boundary > BITS_PER_UNIT)
5460 if (offset_ptr->var)
5463 #ifdef ARGS_GROW_DOWNWARD
5468 (ARGS_SIZE_TREE (*offset_ptr),
5469 boundary / BITS_PER_UNIT);
5470 offset_ptr->constant = 0; /*?*/
5471 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5472 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5477 offset_ptr->constant =
5478 #ifdef ARGS_GROW_DOWNWARD
5479 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5481 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5483 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5484 alignment_pad->constant = offset_ptr->constant - save_constant;
5490 pad_below (offset_ptr, passed_mode, sizetree)
5491 struct args_size *offset_ptr;
5492 enum machine_mode passed_mode;
5495 if (passed_mode != BLKmode)
5497 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5498 offset_ptr->constant
5499 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5500 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5501 - GET_MODE_SIZE (passed_mode));
5505 if (TREE_CODE (sizetree) != INTEGER_CST
5506 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5508 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5509 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5511 ADD_PARM_SIZE (*offset_ptr, s2);
5512 SUB_PARM_SIZE (*offset_ptr, sizetree);
5517 /* Walk the tree of blocks describing the binding levels within a function
5518 and warn about uninitialized variables.
5519 This is done after calling flow_analysis and before global_alloc
5520 clobbers the pseudo-regs to hard regs. */
5523 uninitialized_vars_warning (block)
5527 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5529 if (warn_uninitialized
5530 && TREE_CODE (decl) == VAR_DECL
5531 /* These warnings are unreliable for and aggregates
5532 because assigning the fields one by one can fail to convince
5533 flow.c that the entire aggregate was initialized.
5534 Unions are troublesome because members may be shorter. */
5535 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5536 && DECL_RTL (decl) != 0
5537 && GET_CODE (DECL_RTL (decl)) == REG
5538 /* Global optimizations can make it difficult to determine if a
5539 particular variable has been initialized. However, a VAR_DECL
5540 with a nonzero DECL_INITIAL had an initializer, so do not
5541 claim it is potentially uninitialized.
5543 We do not care about the actual value in DECL_INITIAL, so we do
5544 not worry that it may be a dangling pointer. */
5545 && DECL_INITIAL (decl) == NULL_TREE
5546 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5547 warning_with_decl (decl,
5548 "`%s' might be used uninitialized in this function");
5550 && TREE_CODE (decl) == VAR_DECL
5551 && DECL_RTL (decl) != 0
5552 && GET_CODE (DECL_RTL (decl)) == REG
5553 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5554 warning_with_decl (decl,
5555 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5557 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5558 uninitialized_vars_warning (sub);
5561 /* Do the appropriate part of uninitialized_vars_warning
5562 but for arguments instead of local variables. */
5565 setjmp_args_warning ()
5568 for (decl = DECL_ARGUMENTS (current_function_decl);
5569 decl; decl = TREE_CHAIN (decl))
5570 if (DECL_RTL (decl) != 0
5571 && GET_CODE (DECL_RTL (decl)) == REG
5572 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5573 warning_with_decl (decl,
5574 "argument `%s' might be clobbered by `longjmp' or `vfork'");
5577 /* If this function call setjmp, put all vars into the stack
5578 unless they were declared `register'. */
5581 setjmp_protect (block)
5585 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5586 if ((TREE_CODE (decl) == VAR_DECL
5587 || TREE_CODE (decl) == PARM_DECL)
5588 && DECL_RTL (decl) != 0
5589 && (GET_CODE (DECL_RTL (decl)) == REG
5590 || (GET_CODE (DECL_RTL (decl)) == MEM
5591 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5592 /* If this variable came from an inline function, it must be
5593 that its life doesn't overlap the setjmp. If there was a
5594 setjmp in the function, it would already be in memory. We
5595 must exclude such variable because their DECL_RTL might be
5596 set to strange things such as virtual_stack_vars_rtx. */
5597 && ! DECL_FROM_INLINE (decl)
5599 #ifdef NON_SAVING_SETJMP
5600 /* If longjmp doesn't restore the registers,
5601 don't put anything in them. */
5605 ! DECL_REGISTER (decl)))
5606 put_var_into_stack (decl, /*rescan=*/true);
5607 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5608 setjmp_protect (sub);
5611 /* Like the previous function, but for args instead of local variables. */
5614 setjmp_protect_args ()
5617 for (decl = DECL_ARGUMENTS (current_function_decl);
5618 decl; decl = TREE_CHAIN (decl))
5619 if ((TREE_CODE (decl) == VAR_DECL
5620 || TREE_CODE (decl) == PARM_DECL)
5621 && DECL_RTL (decl) != 0
5622 && (GET_CODE (DECL_RTL (decl)) == REG
5623 || (GET_CODE (DECL_RTL (decl)) == MEM
5624 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5626 /* If longjmp doesn't restore the registers,
5627 don't put anything in them. */
5628 #ifdef NON_SAVING_SETJMP
5632 ! DECL_REGISTER (decl)))
5633 put_var_into_stack (decl, /*rescan=*/true);
5636 /* Return the context-pointer register corresponding to DECL,
5637 or 0 if it does not need one. */
5640 lookup_static_chain (decl)
5643 tree context = decl_function_context (decl);
5647 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5650 /* We treat inline_function_decl as an alias for the current function
5651 because that is the inline function whose vars, types, etc.
5652 are being merged into the current function.
5653 See expand_inline_function. */
5654 if (context == current_function_decl || context == inline_function_decl)
5655 return virtual_stack_vars_rtx;
5657 for (link = context_display; link; link = TREE_CHAIN (link))
5658 if (TREE_PURPOSE (link) == context)
5659 return RTL_EXPR_RTL (TREE_VALUE (link));
5664 /* Convert a stack slot address ADDR for variable VAR
5665 (from a containing function)
5666 into an address valid in this function (using a static chain). */
5669 fix_lexical_addr (addr, var)
5674 HOST_WIDE_INT displacement;
5675 tree context = decl_function_context (var);
5676 struct function *fp;
5679 /* If this is the present function, we need not do anything. */
5680 if (context == current_function_decl || context == inline_function_decl)
5683 fp = find_function_data (context);
5685 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5686 addr = XEXP (XEXP (addr, 0), 0);
5688 /* Decode given address as base reg plus displacement. */
5689 if (GET_CODE (addr) == REG)
5690 basereg = addr, displacement = 0;
5691 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5692 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5696 /* We accept vars reached via the containing function's
5697 incoming arg pointer and via its stack variables pointer. */
5698 if (basereg == fp->internal_arg_pointer)
5700 /* If reached via arg pointer, get the arg pointer value
5701 out of that function's stack frame.
5703 There are two cases: If a separate ap is needed, allocate a
5704 slot in the outer function for it and dereference it that way.
5705 This is correct even if the real ap is actually a pseudo.
5706 Otherwise, just adjust the offset from the frame pointer to
5709 #ifdef NEED_SEPARATE_AP
5712 addr = get_arg_pointer_save_area (fp);
5713 addr = fix_lexical_addr (XEXP (addr, 0), var);
5714 addr = memory_address (Pmode, addr);
5716 base = gen_rtx_MEM (Pmode, addr);
5717 set_mem_alias_set (base, get_frame_alias_set ());
5718 base = copy_to_reg (base);
5720 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5721 base = lookup_static_chain (var);
5725 else if (basereg == virtual_stack_vars_rtx)
5727 /* This is the same code as lookup_static_chain, duplicated here to
5728 avoid an extra call to decl_function_context. */
5731 for (link = context_display; link; link = TREE_CHAIN (link))
5732 if (TREE_PURPOSE (link) == context)
5734 base = RTL_EXPR_RTL (TREE_VALUE (link));
5742 /* Use same offset, relative to appropriate static chain or argument
5744 return plus_constant (base, displacement);
5747 /* Return the address of the trampoline for entering nested fn FUNCTION.
5748 If necessary, allocate a trampoline (in the stack frame)
5749 and emit rtl to initialize its contents (at entry to this function). */
5752 trampoline_address (function)
5758 struct function *fp;
5761 /* Find an existing trampoline and return it. */
5762 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5763 if (TREE_PURPOSE (link) == function)
5765 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5767 for (fp = outer_function_chain; fp; fp = fp->outer)
5768 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5769 if (TREE_PURPOSE (link) == function)
5771 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5773 return adjust_trampoline_addr (tramp);
5776 /* None exists; we must make one. */
5778 /* Find the `struct function' for the function containing FUNCTION. */
5780 fn_context = decl_function_context (function);
5781 if (fn_context != current_function_decl
5782 && fn_context != inline_function_decl)
5783 fp = find_function_data (fn_context);
5785 /* Allocate run-time space for this trampoline
5786 (usually in the defining function's stack frame). */
5787 #ifdef ALLOCATE_TRAMPOLINE
5788 tramp = ALLOCATE_TRAMPOLINE (fp);
5790 /* If rounding needed, allocate extra space
5791 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5792 #define TRAMPOLINE_REAL_SIZE \
5793 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5794 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5798 /* Record the trampoline for reuse and note it for later initialization
5799 by expand_function_end. */
5802 rtlexp = make_node (RTL_EXPR);
5803 RTL_EXPR_RTL (rtlexp) = tramp;
5804 fp->x_trampoline_list = tree_cons (function, rtlexp,
5805 fp->x_trampoline_list);
5809 /* Make the RTL_EXPR node temporary, not momentary, so that the
5810 trampoline_list doesn't become garbage. */
5811 rtlexp = make_node (RTL_EXPR);
5813 RTL_EXPR_RTL (rtlexp) = tramp;
5814 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5817 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5818 return adjust_trampoline_addr (tramp);
5821 /* Given a trampoline address,
5822 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5825 round_trampoline_addr (tramp)
5828 /* Round address up to desired boundary. */
5829 rtx temp = gen_reg_rtx (Pmode);
5830 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
5831 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5833 temp = expand_simple_binop (Pmode, PLUS, tramp, addend,
5834 temp, 0, OPTAB_LIB_WIDEN);
5835 tramp = expand_simple_binop (Pmode, AND, temp, mask,
5836 temp, 0, OPTAB_LIB_WIDEN);
5841 /* Given a trampoline address, round it then apply any
5842 platform-specific adjustments so that the result can be used for a
5846 adjust_trampoline_addr (tramp)
5849 tramp = round_trampoline_addr (tramp);
5850 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5851 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5856 /* Put all this function's BLOCK nodes including those that are chained
5857 onto the first block into a vector, and return it.
5858 Also store in each NOTE for the beginning or end of a block
5859 the index of that block in the vector.
5860 The arguments are BLOCK, the chain of top-level blocks of the function,
5861 and INSNS, the insn chain of the function. */
5867 tree *block_vector, *last_block_vector;
5869 tree block = DECL_INITIAL (current_function_decl);
5874 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5875 depth-first order. */
5876 block_vector = get_block_vector (block, &n_blocks);
5877 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5879 last_block_vector = identify_blocks_1 (get_insns (),
5881 block_vector + n_blocks,
5884 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5885 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5886 if (0 && last_block_vector != block_vector + n_blocks)
5889 free (block_vector);
5893 /* Subroutine of identify_blocks. Do the block substitution on the
5894 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5896 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5897 BLOCK_VECTOR is incremented for each block seen. */
5900 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5903 tree *end_block_vector;
5904 tree *orig_block_stack;
5907 tree *block_stack = orig_block_stack;
5909 for (insn = insns; insn; insn = NEXT_INSN (insn))
5911 if (GET_CODE (insn) == NOTE)
5913 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5917 /* If there are more block notes than BLOCKs, something
5919 if (block_vector == end_block_vector)
5922 b = *block_vector++;
5923 NOTE_BLOCK (insn) = b;
5926 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5928 /* If there are more NOTE_INSN_BLOCK_ENDs than
5929 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5930 if (block_stack == orig_block_stack)
5933 NOTE_BLOCK (insn) = *--block_stack;
5936 else if (GET_CODE (insn) == CALL_INSN
5937 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5939 rtx cp = PATTERN (insn);
5941 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5942 end_block_vector, block_stack);
5944 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5945 end_block_vector, block_stack);
5947 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5948 end_block_vector, block_stack);
5952 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5953 something is badly wrong. */
5954 if (block_stack != orig_block_stack)
5957 return block_vector;
5960 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5961 and create duplicate blocks. */
5962 /* ??? Need an option to either create block fragments or to create
5963 abstract origin duplicates of a source block. It really depends
5964 on what optimization has been performed. */
5969 tree block = DECL_INITIAL (current_function_decl);
5970 varray_type block_stack;
5972 if (block == NULL_TREE)
5975 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5977 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
5978 reorder_blocks_0 (block);
5980 /* Prune the old trees away, so that they don't get in the way. */
5981 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5982 BLOCK_CHAIN (block) = NULL_TREE;
5984 /* Recreate the block tree from the note nesting. */
5985 reorder_blocks_1 (get_insns (), block, &block_stack);
5986 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5988 /* Remove deleted blocks from the block fragment chains. */
5989 reorder_fix_fragments (block);
5992 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
5995 reorder_blocks_0 (block)
6000 TREE_ASM_WRITTEN (block) = 0;
6001 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
6002 block = BLOCK_CHAIN (block);
6007 reorder_blocks_1 (insns, current_block, p_block_stack)
6010 varray_type *p_block_stack;
6014 for (insn = insns; insn; insn = NEXT_INSN (insn))
6016 if (GET_CODE (insn) == NOTE)
6018 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
6020 tree block = NOTE_BLOCK (insn);
6022 /* If we have seen this block before, that means it now
6023 spans multiple address regions. Create a new fragment. */
6024 if (TREE_ASM_WRITTEN (block))
6026 tree new_block = copy_node (block);
6029 origin = (BLOCK_FRAGMENT_ORIGIN (block)
6030 ? BLOCK_FRAGMENT_ORIGIN (block)
6032 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
6033 BLOCK_FRAGMENT_CHAIN (new_block)
6034 = BLOCK_FRAGMENT_CHAIN (origin);
6035 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
6037 NOTE_BLOCK (insn) = new_block;
6041 BLOCK_SUBBLOCKS (block) = 0;
6042 TREE_ASM_WRITTEN (block) = 1;
6043 /* When there's only one block for the entire function,
6044 current_block == block and we mustn't do this, it
6045 will cause infinite recursion. */
6046 if (block != current_block)
6048 BLOCK_SUPERCONTEXT (block) = current_block;
6049 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
6050 BLOCK_SUBBLOCKS (current_block) = block;
6051 current_block = block;
6053 VARRAY_PUSH_TREE (*p_block_stack, block);
6055 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
6057 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
6058 VARRAY_POP (*p_block_stack);
6059 BLOCK_SUBBLOCKS (current_block)
6060 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
6061 current_block = BLOCK_SUPERCONTEXT (current_block);
6064 else if (GET_CODE (insn) == CALL_INSN
6065 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
6067 rtx cp = PATTERN (insn);
6068 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
6070 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
6072 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
6077 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
6078 appears in the block tree, select one of the fragments to become
6079 the new origin block. */
6082 reorder_fix_fragments (block)
6087 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
6088 tree new_origin = NULL_TREE;
6092 if (! TREE_ASM_WRITTEN (dup_origin))
6094 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
6096 /* Find the first of the remaining fragments. There must
6097 be at least one -- the current block. */
6098 while (! TREE_ASM_WRITTEN (new_origin))
6099 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
6100 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
6103 else if (! dup_origin)
6106 /* Re-root the rest of the fragments to the new origin. In the
6107 case that DUP_ORIGIN was null, that means BLOCK was the origin
6108 of a chain of fragments and we want to remove those fragments
6109 that didn't make it to the output. */
6112 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
6117 if (TREE_ASM_WRITTEN (chain))
6119 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
6121 pp = &BLOCK_FRAGMENT_CHAIN (chain);
6123 chain = BLOCK_FRAGMENT_CHAIN (chain);
6128 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
6129 block = BLOCK_CHAIN (block);
6133 /* Reverse the order of elements in the chain T of blocks,
6134 and return the new head of the chain (old last element). */
6140 tree prev = 0, decl, next;
6141 for (decl = t; decl; decl = next)
6143 next = BLOCK_CHAIN (decl);
6144 BLOCK_CHAIN (decl) = prev;
6150 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6151 non-NULL, list them all into VECTOR, in a depth-first preorder
6152 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6156 all_blocks (block, vector)
6164 TREE_ASM_WRITTEN (block) = 0;
6166 /* Record this block. */
6168 vector[n_blocks] = block;
6172 /* Record the subblocks, and their subblocks... */
6173 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6174 vector ? vector + n_blocks : 0);
6175 block = BLOCK_CHAIN (block);
6181 /* Return a vector containing all the blocks rooted at BLOCK. The
6182 number of elements in the vector is stored in N_BLOCKS_P. The
6183 vector is dynamically allocated; it is the caller's responsibility
6184 to call `free' on the pointer returned. */
6187 get_block_vector (block, n_blocks_p)
6193 *n_blocks_p = all_blocks (block, NULL);
6194 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
6195 all_blocks (block, block_vector);
6197 return block_vector;
6200 static GTY(()) int next_block_index = 2;
6202 /* Set BLOCK_NUMBER for all the blocks in FN. */
6212 /* For SDB and XCOFF debugging output, we start numbering the blocks
6213 from 1 within each function, rather than keeping a running
6215 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6216 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6217 next_block_index = 1;
6220 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6222 /* The top-level BLOCK isn't numbered at all. */
6223 for (i = 1; i < n_blocks; ++i)
6224 /* We number the blocks from two. */
6225 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6227 free (block_vector);
6232 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6235 debug_find_var_in_block_tree (var, block)
6241 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6245 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6247 tree ret = debug_find_var_in_block_tree (var, t);
6255 /* Allocate a function structure and reset its contents to the defaults. */
6258 prepare_function_start ()
6260 cfun = (struct function *) ggc_alloc_cleared (sizeof (struct function));
6262 init_stmt_for_function ();
6263 init_eh_for_function ();
6265 cse_not_expected = ! optimize;
6267 /* Caller save not needed yet. */
6268 caller_save_needed = 0;
6270 /* No stack slots have been made yet. */
6271 stack_slot_list = 0;
6273 current_function_has_nonlocal_label = 0;
6274 current_function_has_nonlocal_goto = 0;
6276 /* There is no stack slot for handling nonlocal gotos. */
6277 nonlocal_goto_handler_slots = 0;
6278 nonlocal_goto_stack_level = 0;
6280 /* No labels have been declared for nonlocal use. */
6281 nonlocal_labels = 0;
6282 nonlocal_goto_handler_labels = 0;
6284 /* No function calls so far in this function. */
6285 function_call_count = 0;
6287 /* No parm regs have been allocated.
6288 (This is important for output_inline_function.) */
6289 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6291 /* Initialize the RTL mechanism. */
6294 /* Initialize the queue of pending postincrement and postdecrements,
6295 and some other info in expr.c. */
6298 /* We haven't done register allocation yet. */
6301 init_varasm_status (cfun);
6303 /* Clear out data used for inlining. */
6304 cfun->inlinable = 0;
6305 cfun->original_decl_initial = 0;
6306 cfun->original_arg_vector = 0;
6308 cfun->stack_alignment_needed = STACK_BOUNDARY;
6309 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6311 /* Set if a call to setjmp is seen. */
6312 current_function_calls_setjmp = 0;
6314 /* Set if a call to longjmp is seen. */
6315 current_function_calls_longjmp = 0;
6317 current_function_calls_alloca = 0;
6318 current_function_calls_eh_return = 0;
6319 current_function_calls_constant_p = 0;
6320 current_function_contains_functions = 0;
6321 current_function_is_leaf = 0;
6322 current_function_nothrow = 0;
6323 current_function_sp_is_unchanging = 0;
6324 current_function_uses_only_leaf_regs = 0;
6325 current_function_has_computed_jump = 0;
6326 current_function_is_thunk = 0;
6328 current_function_returns_pcc_struct = 0;
6329 current_function_returns_struct = 0;
6330 current_function_epilogue_delay_list = 0;
6331 current_function_uses_const_pool = 0;
6332 current_function_uses_pic_offset_table = 0;
6333 current_function_cannot_inline = 0;
6335 /* We have not yet needed to make a label to jump to for tail-recursion. */
6336 tail_recursion_label = 0;
6338 /* We haven't had a need to make a save area for ap yet. */
6339 arg_pointer_save_area = 0;
6341 /* No stack slots allocated yet. */
6344 /* No SAVE_EXPRs in this function yet. */
6347 /* No RTL_EXPRs in this function yet. */
6350 /* Set up to allocate temporaries. */
6353 /* Indicate that we need to distinguish between the return value of the
6354 present function and the return value of a function being called. */
6355 rtx_equal_function_value_matters = 1;
6357 /* Indicate that we have not instantiated virtual registers yet. */
6358 virtuals_instantiated = 0;
6360 /* Indicate that we want CONCATs now. */
6361 generating_concat_p = 1;
6363 /* Indicate we have no need of a frame pointer yet. */
6364 frame_pointer_needed = 0;
6366 /* By default assume not stdarg. */
6367 current_function_stdarg = 0;
6369 /* We haven't made any trampolines for this function yet. */
6370 trampoline_list = 0;
6372 init_pending_stack_adjust ();
6373 inhibit_defer_pop = 0;
6375 current_function_outgoing_args_size = 0;
6377 current_function_funcdef_no = funcdef_no++;
6379 cfun->arc_profile = profile_arc_flag || flag_test_coverage;
6381 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
6383 cfun->max_jumptable_ents = 0;
6385 (*lang_hooks.function.init) (cfun);
6386 if (init_machine_status)
6387 cfun->machine = (*init_machine_status) ();
6390 /* Initialize the rtl expansion mechanism so that we can do simple things
6391 like generate sequences. This is used to provide a context during global
6392 initialization of some passes. */
6394 init_dummy_function_start ()
6396 prepare_function_start ();
6399 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6400 and initialize static variables for generating RTL for the statements
6404 init_function_start (subr, filename, line)
6406 const char *filename;
6409 prepare_function_start ();
6411 current_function_name = (*lang_hooks.decl_printable_name) (subr, 2);
6414 /* Nonzero if this is a nested function that uses a static chain. */
6416 current_function_needs_context
6417 = (decl_function_context (current_function_decl) != 0
6418 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6420 /* Within function body, compute a type's size as soon it is laid out. */
6421 immediate_size_expand++;
6423 /* Prevent ever trying to delete the first instruction of a function.
6424 Also tell final how to output a linenum before the function prologue.
6425 Note linenums could be missing, e.g. when compiling a Java .class file. */
6427 emit_line_note (filename, line);
6429 /* Make sure first insn is a note even if we don't want linenums.
6430 This makes sure the first insn will never be deleted.
6431 Also, final expects a note to appear there. */
6432 emit_note (NULL, NOTE_INSN_DELETED);
6434 /* Set flags used by final.c. */
6435 if (aggregate_value_p (DECL_RESULT (subr)))
6437 #ifdef PCC_STATIC_STRUCT_RETURN
6438 current_function_returns_pcc_struct = 1;
6440 current_function_returns_struct = 1;
6443 /* Warn if this value is an aggregate type,
6444 regardless of which calling convention we are using for it. */
6445 if (warn_aggregate_return
6446 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6447 warning ("function returns an aggregate");
6449 current_function_returns_pointer
6450 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
6453 /* Make sure all values used by the optimization passes have sane
6456 init_function_for_compilation ()
6460 /* No prologue/epilogue insns yet. */
6461 VARRAY_GROW (prologue, 0);
6462 VARRAY_GROW (epilogue, 0);
6463 VARRAY_GROW (sibcall_epilogue, 0);
6466 /* Expand a call to __main at the beginning of a possible main function. */
6468 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6469 #undef HAS_INIT_SECTION
6470 #define HAS_INIT_SECTION
6474 expand_main_function ()
6476 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6477 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6479 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6483 /* Forcibly align the stack. */
6484 #ifdef STACK_GROWS_DOWNWARD
6485 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6486 stack_pointer_rtx, 1, OPTAB_WIDEN);
6488 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6489 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6490 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6491 stack_pointer_rtx, 1, OPTAB_WIDEN);
6493 if (tmp != stack_pointer_rtx)
6494 emit_move_insn (stack_pointer_rtx, tmp);
6496 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6497 tmp = force_reg (Pmode, const0_rtx);
6498 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6502 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6503 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6506 emit_insn_before (seq, tmp);
6512 #ifndef HAS_INIT_SECTION
6513 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
6517 /* The PENDING_SIZES represent the sizes of variable-sized types.
6518 Create RTL for the various sizes now (using temporary variables),
6519 so that we can refer to the sizes from the RTL we are generating
6520 for the current function. The PENDING_SIZES are a TREE_LIST. The
6521 TREE_VALUE of each node is a SAVE_EXPR. */
6524 expand_pending_sizes (pending_sizes)
6529 /* Evaluate now the sizes of any types declared among the arguments. */
6530 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6532 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6533 /* Flush the queue in case this parameter declaration has
6539 /* Start the RTL for a new function, and set variables used for
6541 SUBR is the FUNCTION_DECL node.
6542 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6543 the function's parameters, which must be run at any return statement. */
6546 expand_function_start (subr, parms_have_cleanups)
6548 int parms_have_cleanups;
6551 rtx last_ptr = NULL_RTX;
6553 /* Make sure volatile mem refs aren't considered
6554 valid operands of arithmetic insns. */
6555 init_recog_no_volatile ();
6557 current_function_instrument_entry_exit
6558 = (flag_instrument_function_entry_exit
6559 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6561 current_function_profile
6563 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6565 current_function_limit_stack
6566 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6568 /* If function gets a static chain arg, store it in the stack frame.
6569 Do this first, so it gets the first stack slot offset. */
6570 if (current_function_needs_context)
6572 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6574 /* Delay copying static chain if it is not a register to avoid
6575 conflicts with regs used for parameters. */
6576 if (! SMALL_REGISTER_CLASSES
6577 || GET_CODE (static_chain_incoming_rtx) == REG)
6578 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6581 /* If the parameters of this function need cleaning up, get a label
6582 for the beginning of the code which executes those cleanups. This must
6583 be done before doing anything with return_label. */
6584 if (parms_have_cleanups)
6585 cleanup_label = gen_label_rtx ();
6589 /* Make the label for return statements to jump to. Do not special
6590 case machines with special return instructions -- they will be
6591 handled later during jump, ifcvt, or epilogue creation. */
6592 return_label = gen_label_rtx ();
6594 /* Initialize rtx used to return the value. */
6595 /* Do this before assign_parms so that we copy the struct value address
6596 before any library calls that assign parms might generate. */
6598 /* Decide whether to return the value in memory or in a register. */
6599 if (aggregate_value_p (DECL_RESULT (subr)))
6601 /* Returning something that won't go in a register. */
6602 rtx value_address = 0;
6604 #ifdef PCC_STATIC_STRUCT_RETURN
6605 if (current_function_returns_pcc_struct)
6607 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6608 value_address = assemble_static_space (size);
6613 /* Expect to be passed the address of a place to store the value.
6614 If it is passed as an argument, assign_parms will take care of
6616 if (struct_value_incoming_rtx)
6618 value_address = gen_reg_rtx (Pmode);
6619 emit_move_insn (value_address, struct_value_incoming_rtx);
6624 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6625 set_mem_attributes (x, DECL_RESULT (subr), 1);
6626 SET_DECL_RTL (DECL_RESULT (subr), x);
6629 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6630 /* If return mode is void, this decl rtl should not be used. */
6631 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6634 /* Compute the return values into a pseudo reg, which we will copy
6635 into the true return register after the cleanups are done. */
6637 /* In order to figure out what mode to use for the pseudo, we
6638 figure out what the mode of the eventual return register will
6639 actually be, and use that. */
6641 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6644 /* Structures that are returned in registers are not aggregate_value_p,
6645 so we may see a PARALLEL or a REG. */
6646 if (REG_P (hard_reg))
6647 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6648 else if (GET_CODE (hard_reg) == PARALLEL)
6649 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
6653 /* Set DECL_REGISTER flag so that expand_function_end will copy the
6654 result to the real return register(s). */
6655 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6658 /* Initialize rtx for parameters and local variables.
6659 In some cases this requires emitting insns. */
6661 assign_parms (subr);
6663 /* Copy the static chain now if it wasn't a register. The delay is to
6664 avoid conflicts with the parameter passing registers. */
6666 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6667 if (GET_CODE (static_chain_incoming_rtx) != REG)
6668 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6670 /* The following was moved from init_function_start.
6671 The move is supposed to make sdb output more accurate. */
6672 /* Indicate the beginning of the function body,
6673 as opposed to parm setup. */
6674 emit_note (NULL, NOTE_INSN_FUNCTION_BEG);
6676 if (GET_CODE (get_last_insn ()) != NOTE)
6677 emit_note (NULL, NOTE_INSN_DELETED);
6678 parm_birth_insn = get_last_insn ();
6680 context_display = 0;
6681 if (current_function_needs_context)
6683 /* Fetch static chain values for containing functions. */
6684 tem = decl_function_context (current_function_decl);
6685 /* Copy the static chain pointer into a pseudo. If we have
6686 small register classes, copy the value from memory if
6687 static_chain_incoming_rtx is a REG. */
6690 /* If the static chain originally came in a register, put it back
6691 there, then move it out in the next insn. The reason for
6692 this peculiar code is to satisfy function integration. */
6693 if (SMALL_REGISTER_CLASSES
6694 && GET_CODE (static_chain_incoming_rtx) == REG)
6695 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6696 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6701 tree rtlexp = make_node (RTL_EXPR);
6703 RTL_EXPR_RTL (rtlexp) = last_ptr;
6704 context_display = tree_cons (tem, rtlexp, context_display);
6705 tem = decl_function_context (tem);
6708 /* Chain thru stack frames, assuming pointer to next lexical frame
6709 is found at the place we always store it. */
6710 #ifdef FRAME_GROWS_DOWNWARD
6711 last_ptr = plus_constant (last_ptr,
6712 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6714 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6715 set_mem_alias_set (last_ptr, get_frame_alias_set ());
6716 last_ptr = copy_to_reg (last_ptr);
6718 /* If we are not optimizing, ensure that we know that this
6719 piece of context is live over the entire function. */
6721 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6726 if (current_function_instrument_entry_exit)
6728 rtx fun = DECL_RTL (current_function_decl);
6729 if (GET_CODE (fun) == MEM)
6730 fun = XEXP (fun, 0);
6733 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode,
6735 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6737 hard_frame_pointer_rtx),
6741 if (current_function_profile)
6744 PROFILE_HOOK (current_function_funcdef_no);
6748 /* After the display initializations is where the tail-recursion label
6749 should go, if we end up needing one. Ensure we have a NOTE here
6750 since some things (like trampolines) get placed before this. */
6751 tail_recursion_reentry = emit_note (NULL, NOTE_INSN_DELETED);
6753 /* Evaluate now the sizes of any types declared among the arguments. */
6754 expand_pending_sizes (nreverse (get_pending_sizes ()));
6756 /* Make sure there is a line number after the function entry setup code. */
6757 force_next_line_note ();
6760 /* Undo the effects of init_dummy_function_start. */
6762 expand_dummy_function_end ()
6764 /* End any sequences that failed to be closed due to syntax errors. */
6765 while (in_sequence_p ())
6768 /* Outside function body, can't compute type's actual size
6769 until next function's body starts. */
6771 free_after_parsing (cfun);
6772 free_after_compilation (cfun);
6776 /* Call DOIT for each hard register used as a return value from
6777 the current function. */
6780 diddle_return_value (doit, arg)
6781 void (*doit) PARAMS ((rtx, void *));
6784 rtx outgoing = current_function_return_rtx;
6789 if (GET_CODE (outgoing) == REG)
6790 (*doit) (outgoing, arg);
6791 else if (GET_CODE (outgoing) == PARALLEL)
6795 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6797 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6799 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6806 do_clobber_return_reg (reg, arg)
6808 void *arg ATTRIBUTE_UNUSED;
6810 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6814 clobber_return_register ()
6816 diddle_return_value (do_clobber_return_reg, NULL);
6818 /* In case we do use pseudo to return value, clobber it too. */
6819 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6821 tree decl_result = DECL_RESULT (current_function_decl);
6822 rtx decl_rtl = DECL_RTL (decl_result);
6823 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6825 do_clobber_return_reg (decl_rtl, NULL);
6831 do_use_return_reg (reg, arg)
6833 void *arg ATTRIBUTE_UNUSED;
6835 emit_insn (gen_rtx_USE (VOIDmode, reg));
6839 use_return_register ()
6841 diddle_return_value (do_use_return_reg, NULL);
6844 static GTY(()) rtx initial_trampoline;
6846 /* Generate RTL for the end of the current function.
6847 FILENAME and LINE are the current position in the source file.
6849 It is up to language-specific callers to do cleanups for parameters--
6850 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6853 expand_function_end (filename, line, end_bindings)
6854 const char *filename;
6861 finish_expr_for_function ();
6863 /* If arg_pointer_save_area was referenced only from a nested
6864 function, we will not have initialized it yet. Do that now. */
6865 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6866 get_arg_pointer_save_area (cfun);
6868 #ifdef NON_SAVING_SETJMP
6869 /* Don't put any variables in registers if we call setjmp
6870 on a machine that fails to restore the registers. */
6871 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6873 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6874 setjmp_protect (DECL_INITIAL (current_function_decl));
6876 setjmp_protect_args ();
6880 /* Initialize any trampolines required by this function. */
6881 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6883 tree function = TREE_PURPOSE (link);
6884 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6885 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6886 #ifdef TRAMPOLINE_TEMPLATE
6891 #ifdef TRAMPOLINE_TEMPLATE
6892 /* First make sure this compilation has a template for
6893 initializing trampolines. */
6894 if (initial_trampoline == 0)
6897 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6898 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
6902 /* Generate insns to initialize the trampoline. */
6904 tramp = round_trampoline_addr (XEXP (tramp, 0));
6905 #ifdef TRAMPOLINE_TEMPLATE
6906 blktramp = replace_equiv_address (initial_trampoline, tramp);
6907 emit_block_move (blktramp, initial_trampoline,
6908 GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL);
6910 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6914 /* Put those insns at entry to the containing function (this one). */
6915 emit_insn_before (seq, tail_recursion_reentry);
6918 /* If we are doing stack checking and this function makes calls,
6919 do a stack probe at the start of the function to ensure we have enough
6920 space for another stack frame. */
6921 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6925 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6926 if (GET_CODE (insn) == CALL_INSN)
6929 probe_stack_range (STACK_CHECK_PROTECT,
6930 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6933 emit_insn_before (seq, tail_recursion_reentry);
6938 /* Warn about unused parms if extra warnings were specified. */
6939 /* Either ``-Wextra -Wunused'' or ``-Wunused-parameter'' enables this
6940 warning. WARN_UNUSED_PARAMETER is negative when set by
6941 -Wunused. Note that -Wall implies -Wunused, so ``-Wall -Wextra'' will
6942 also give these warnings. */
6943 if (warn_unused_parameter > 0
6944 || (warn_unused_parameter < 0 && extra_warnings))
6948 for (decl = DECL_ARGUMENTS (current_function_decl);
6949 decl; decl = TREE_CHAIN (decl))
6950 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6951 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6952 warning_with_decl (decl, "unused parameter `%s'");
6955 /* Delete handlers for nonlocal gotos if nothing uses them. */
6956 if (nonlocal_goto_handler_slots != 0
6957 && ! current_function_has_nonlocal_label)
6960 /* End any sequences that failed to be closed due to syntax errors. */
6961 while (in_sequence_p ())
6964 /* Outside function body, can't compute type's actual size
6965 until next function's body starts. */
6966 immediate_size_expand--;
6968 clear_pending_stack_adjust ();
6969 do_pending_stack_adjust ();
6971 /* Mark the end of the function body.
6972 If control reaches this insn, the function can drop through
6973 without returning a value. */
6974 emit_note (NULL, NOTE_INSN_FUNCTION_END);
6976 /* Must mark the last line number note in the function, so that the test
6977 coverage code can avoid counting the last line twice. This just tells
6978 the code to ignore the immediately following line note, since there
6979 already exists a copy of this note somewhere above. This line number
6980 note is still needed for debugging though, so we can't delete it. */
6981 if (flag_test_coverage)
6982 emit_note (NULL, NOTE_INSN_REPEATED_LINE_NUMBER);
6984 /* Output a linenumber for the end of the function.
6985 SDB depends on this. */
6986 emit_line_note_force (filename, line);
6988 /* Before the return label (if any), clobber the return
6989 registers so that they are not propagated live to the rest of
6990 the function. This can only happen with functions that drop
6991 through; if there had been a return statement, there would
6992 have either been a return rtx, or a jump to the return label.
6994 We delay actual code generation after the current_function_value_rtx
6996 clobber_after = get_last_insn ();
6998 /* Output the label for the actual return from the function,
6999 if one is expected. This happens either because a function epilogue
7000 is used instead of a return instruction, or because a return was done
7001 with a goto in order to run local cleanups, or because of pcc-style
7002 structure returning. */
7004 emit_label (return_label);
7006 /* C++ uses this. */
7008 expand_end_bindings (0, 0, 0);
7010 if (current_function_instrument_entry_exit)
7012 rtx fun = DECL_RTL (current_function_decl);
7013 if (GET_CODE (fun) == MEM)
7014 fun = XEXP (fun, 0);
7017 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode,
7019 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
7021 hard_frame_pointer_rtx),
7025 /* Let except.c know where it should emit the call to unregister
7026 the function context for sjlj exceptions. */
7027 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
7028 sjlj_emit_function_exit_after (get_last_insn ());
7030 /* If we had calls to alloca, and this machine needs
7031 an accurate stack pointer to exit the function,
7032 insert some code to save and restore the stack pointer. */
7033 #ifdef EXIT_IGNORE_STACK
7034 if (! EXIT_IGNORE_STACK)
7036 if (current_function_calls_alloca)
7040 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
7041 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
7044 /* If scalar return value was computed in a pseudo-reg, or was a named
7045 return value that got dumped to the stack, copy that to the hard
7047 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
7049 tree decl_result = DECL_RESULT (current_function_decl);
7050 rtx decl_rtl = DECL_RTL (decl_result);
7052 if (REG_P (decl_rtl)
7053 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
7054 : DECL_REGISTER (decl_result))
7056 rtx real_decl_rtl = current_function_return_rtx;
7058 /* This should be set in assign_parms. */
7059 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
7062 /* If this is a BLKmode structure being returned in registers,
7063 then use the mode computed in expand_return. Note that if
7064 decl_rtl is memory, then its mode may have been changed,
7065 but that current_function_return_rtx has not. */
7066 if (GET_MODE (real_decl_rtl) == BLKmode)
7067 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
7069 /* If a named return value dumped decl_return to memory, then
7070 we may need to re-do the PROMOTE_MODE signed/unsigned
7072 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
7074 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
7076 #ifdef PROMOTE_FUNCTION_RETURN
7077 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
7081 convert_move (real_decl_rtl, decl_rtl, unsignedp);
7083 else if (GET_CODE (real_decl_rtl) == PARALLEL)
7085 /* If expand_function_start has created a PARALLEL for decl_rtl,
7086 move the result to the real return registers. Otherwise, do
7087 a group load from decl_rtl for a named return. */
7088 if (GET_CODE (decl_rtl) == PARALLEL)
7089 emit_group_move (real_decl_rtl, decl_rtl);
7091 emit_group_load (real_decl_rtl, decl_rtl,
7092 int_size_in_bytes (TREE_TYPE (decl_result)));
7095 emit_move_insn (real_decl_rtl, decl_rtl);
7099 /* If returning a structure, arrange to return the address of the value
7100 in a place where debuggers expect to find it.
7102 If returning a structure PCC style,
7103 the caller also depends on this value.
7104 And current_function_returns_pcc_struct is not necessarily set. */
7105 if (current_function_returns_struct
7106 || current_function_returns_pcc_struct)
7109 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
7110 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
7111 #ifdef FUNCTION_OUTGOING_VALUE
7113 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
7114 current_function_decl);
7117 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
7120 /* Mark this as a function return value so integrate will delete the
7121 assignment and USE below when inlining this function. */
7122 REG_FUNCTION_VALUE_P (outgoing) = 1;
7124 #ifdef POINTERS_EXTEND_UNSIGNED
7125 /* The address may be ptr_mode and OUTGOING may be Pmode. */
7126 if (GET_MODE (outgoing) != GET_MODE (value_address))
7127 value_address = convert_memory_address (GET_MODE (outgoing),
7131 emit_move_insn (outgoing, value_address);
7133 /* Show return register used to hold result (in this case the address
7135 current_function_return_rtx = outgoing;
7138 /* If this is an implementation of throw, do what's necessary to
7139 communicate between __builtin_eh_return and the epilogue. */
7140 expand_eh_return ();
7142 /* Emit the actual code to clobber return register. */
7147 clobber_return_register ();
7151 after = emit_insn_after (seq, clobber_after);
7153 if (clobber_after != after)
7154 cfun->x_clobber_return_insn = after;
7157 /* ??? This should no longer be necessary since stupid is no longer with
7158 us, but there are some parts of the compiler (eg reload_combine, and
7159 sh mach_dep_reorg) that still try and compute their own lifetime info
7160 instead of using the general framework. */
7161 use_return_register ();
7163 /* Fix up any gotos that jumped out to the outermost
7164 binding level of the function.
7165 Must follow emitting RETURN_LABEL. */
7167 /* If you have any cleanups to do at this point,
7168 and they need to create temporary variables,
7169 then you will lose. */
7170 expand_fixups (get_insns ());
7174 get_arg_pointer_save_area (f)
7177 rtx ret = f->x_arg_pointer_save_area;
7181 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
7182 f->x_arg_pointer_save_area = ret;
7185 if (f == cfun && ! f->arg_pointer_save_area_init)
7189 /* Save the arg pointer at the beginning of the function. The
7190 generated stack slot may not be a valid memory address, so we
7191 have to check it and fix it if necessary. */
7193 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
7197 push_topmost_sequence ();
7198 emit_insn_after (seq, get_insns ());
7199 pop_topmost_sequence ();
7205 /* Extend a vector that records the INSN_UIDs of INSNS
7206 (a list of one or more insns). */
7209 record_insns (insns, vecp)
7218 while (tmp != NULL_RTX)
7221 tmp = NEXT_INSN (tmp);
7224 i = VARRAY_SIZE (*vecp);
7225 VARRAY_GROW (*vecp, i + len);
7227 while (tmp != NULL_RTX)
7229 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
7231 tmp = NEXT_INSN (tmp);
7235 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
7236 be running after reorg, SEQUENCE rtl is possible. */
7239 contains (insn, vec)
7245 if (GET_CODE (insn) == INSN
7246 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7249 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7250 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7251 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7257 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7258 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7265 prologue_epilogue_contains (insn)
7268 if (contains (insn, prologue))
7270 if (contains (insn, epilogue))
7276 sibcall_epilogue_contains (insn)
7279 if (sibcall_epilogue)
7280 return contains (insn, sibcall_epilogue);
7285 /* Insert gen_return at the end of block BB. This also means updating
7286 block_for_insn appropriately. */
7289 emit_return_into_block (bb, line_note)
7293 emit_jump_insn_after (gen_return (), bb->end);
7295 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
7296 NOTE_LINE_NUMBER (line_note), PREV_INSN (bb->end));
7298 #endif /* HAVE_return */
7300 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7302 /* These functions convert the epilogue into a variant that does not modify the
7303 stack pointer. This is used in cases where a function returns an object
7304 whose size is not known until it is computed. The called function leaves the
7305 object on the stack, leaves the stack depressed, and returns a pointer to
7308 What we need to do is track all modifications and references to the stack
7309 pointer, deleting the modifications and changing the references to point to
7310 the location the stack pointer would have pointed to had the modifications
7313 These functions need to be portable so we need to make as few assumptions
7314 about the epilogue as we can. However, the epilogue basically contains
7315 three things: instructions to reset the stack pointer, instructions to
7316 reload registers, possibly including the frame pointer, and an
7317 instruction to return to the caller.
7319 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7320 We also make no attempt to validate the insns we make since if they are
7321 invalid, we probably can't do anything valid. The intent is that these
7322 routines get "smarter" as more and more machines start to use them and
7323 they try operating on different epilogues.
7325 We use the following structure to track what the part of the epilogue that
7326 we've already processed has done. We keep two copies of the SP equivalence,
7327 one for use during the insn we are processing and one for use in the next
7328 insn. The difference is because one part of a PARALLEL may adjust SP
7329 and the other may use it. */
7333 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7334 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7335 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7336 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7337 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7338 should be set to once we no longer need
7342 static void handle_epilogue_set PARAMS ((rtx, struct epi_info *));
7343 static void emit_equiv_load PARAMS ((struct epi_info *));
7345 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
7346 no modifications to the stack pointer. Return the new list of insns. */
7349 keep_stack_depressed (insns)
7353 struct epi_info info;
7356 /* If the epilogue is just a single instruction, it ust be OK as is. */
7358 if (NEXT_INSN (insns) == NULL_RTX)
7361 /* Otherwise, start a sequence, initialize the information we have, and
7362 process all the insns we were given. */
7365 info.sp_equiv_reg = stack_pointer_rtx;
7367 info.equiv_reg_src = 0;
7371 while (insn != NULL_RTX)
7373 next = NEXT_INSN (insn);
7382 /* If this insn references the register that SP is equivalent to and
7383 we have a pending load to that register, we must force out the load
7384 first and then indicate we no longer know what SP's equivalent is. */
7385 if (info.equiv_reg_src != 0
7386 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7388 emit_equiv_load (&info);
7389 info.sp_equiv_reg = 0;
7392 info.new_sp_equiv_reg = info.sp_equiv_reg;
7393 info.new_sp_offset = info.sp_offset;
7395 /* If this is a (RETURN) and the return address is on the stack,
7396 update the address and change to an indirect jump. */
7397 if (GET_CODE (PATTERN (insn)) == RETURN
7398 || (GET_CODE (PATTERN (insn)) == PARALLEL
7399 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7401 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7403 HOST_WIDE_INT offset = 0;
7404 rtx jump_insn, jump_set;
7406 /* If the return address is in a register, we can emit the insn
7407 unchanged. Otherwise, it must be a MEM and we see what the
7408 base register and offset are. In any case, we have to emit any
7409 pending load to the equivalent reg of SP, if any. */
7410 if (GET_CODE (retaddr) == REG)
7412 emit_equiv_load (&info);
7417 else if (GET_CODE (retaddr) == MEM
7418 && GET_CODE (XEXP (retaddr, 0)) == REG)
7419 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7420 else if (GET_CODE (retaddr) == MEM
7421 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7422 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7423 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7425 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7426 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7431 /* If the base of the location containing the return pointer
7432 is SP, we must update it with the replacement address. Otherwise,
7433 just build the necessary MEM. */
7434 retaddr = plus_constant (base, offset);
7435 if (base == stack_pointer_rtx)
7436 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7437 plus_constant (info.sp_equiv_reg,
7440 retaddr = gen_rtx_MEM (Pmode, retaddr);
7442 /* If there is a pending load to the equivalent register for SP
7443 and we reference that register, we must load our address into
7444 a scratch register and then do that load. */
7445 if (info.equiv_reg_src
7446 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7451 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7452 if (HARD_REGNO_MODE_OK (regno, Pmode)
7453 && !fixed_regs[regno]
7454 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7455 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7457 && !refers_to_regno_p (regno,
7458 regno + HARD_REGNO_NREGS (regno,
7460 info.equiv_reg_src, NULL))
7463 if (regno == FIRST_PSEUDO_REGISTER)
7466 reg = gen_rtx_REG (Pmode, regno);
7467 emit_move_insn (reg, retaddr);
7471 emit_equiv_load (&info);
7472 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7474 /* Show the SET in the above insn is a RETURN. */
7475 jump_set = single_set (jump_insn);
7479 SET_IS_RETURN_P (jump_set) = 1;
7482 /* If SP is not mentioned in the pattern and its equivalent register, if
7483 any, is not modified, just emit it. Otherwise, if neither is set,
7484 replace the reference to SP and emit the insn. If none of those are
7485 true, handle each SET individually. */
7486 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7487 && (info.sp_equiv_reg == stack_pointer_rtx
7488 || !reg_set_p (info.sp_equiv_reg, insn)))
7490 else if (! reg_set_p (stack_pointer_rtx, insn)
7491 && (info.sp_equiv_reg == stack_pointer_rtx
7492 || !reg_set_p (info.sp_equiv_reg, insn)))
7494 if (! validate_replace_rtx (stack_pointer_rtx,
7495 plus_constant (info.sp_equiv_reg,
7502 else if (GET_CODE (PATTERN (insn)) == SET)
7503 handle_epilogue_set (PATTERN (insn), &info);
7504 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7506 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7507 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7508 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7513 info.sp_equiv_reg = info.new_sp_equiv_reg;
7514 info.sp_offset = info.new_sp_offset;
7519 insns = get_insns ();
7524 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7525 structure that contains information about what we've seen so far. We
7526 process this SET by either updating that data or by emitting one or
7530 handle_epilogue_set (set, p)
7534 /* First handle the case where we are setting SP. Record what it is being
7535 set from. If unknown, abort. */
7536 if (reg_set_p (stack_pointer_rtx, set))
7538 if (SET_DEST (set) != stack_pointer_rtx)
7541 if (GET_CODE (SET_SRC (set)) == PLUS
7542 && GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7544 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7545 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7548 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7550 /* If we are adjusting SP, we adjust from the old data. */
7551 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7553 p->new_sp_equiv_reg = p->sp_equiv_reg;
7554 p->new_sp_offset += p->sp_offset;
7557 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7563 /* Next handle the case where we are setting SP's equivalent register.
7564 If we already have a value to set it to, abort. We could update, but
7565 there seems little point in handling that case. Note that we have
7566 to allow for the case where we are setting the register set in
7567 the previous part of a PARALLEL inside a single insn. But use the
7568 old offset for any updates within this insn. */
7569 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7571 if (!rtx_equal_p (p->new_sp_equiv_reg, SET_DEST (set))
7572 || p->equiv_reg_src != 0)
7576 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7577 plus_constant (p->sp_equiv_reg,
7581 /* Otherwise, replace any references to SP in the insn to its new value
7582 and emit the insn. */
7585 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7586 plus_constant (p->sp_equiv_reg,
7588 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7589 plus_constant (p->sp_equiv_reg,
7595 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7601 if (p->equiv_reg_src != 0)
7602 emit_move_insn (p->sp_equiv_reg, p->equiv_reg_src);
7604 p->equiv_reg_src = 0;
7608 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7609 this into place with notes indicating where the prologue ends and where
7610 the epilogue begins. Update the basic block information when possible. */
7613 thread_prologue_and_epilogue_insns (f)
7614 rtx f ATTRIBUTE_UNUSED;
7618 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7621 #ifdef HAVE_prologue
7622 rtx prologue_end = NULL_RTX;
7624 #if defined (HAVE_epilogue) || defined(HAVE_return)
7625 rtx epilogue_end = NULL_RTX;
7628 #ifdef HAVE_prologue
7632 seq = gen_prologue ();
7635 /* Retain a map of the prologue insns. */
7636 record_insns (seq, &prologue);
7637 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
7642 /* Can't deal with multiple successors of the entry block
7643 at the moment. Function should always have at least one
7645 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7648 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7653 /* If the exit block has no non-fake predecessors, we don't need
7655 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7656 if ((e->flags & EDGE_FAKE) == 0)
7662 if (optimize && HAVE_return)
7664 /* If we're allowed to generate a simple return instruction,
7665 then by definition we don't need a full epilogue. Examine
7666 the block that falls through to EXIT. If it does not
7667 contain any code, examine its predecessors and try to
7668 emit (conditional) return instructions. */
7674 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7675 if (e->flags & EDGE_FALLTHRU)
7681 /* Verify that there are no active instructions in the last block. */
7683 while (label && GET_CODE (label) != CODE_LABEL)
7685 if (active_insn_p (label))
7687 label = PREV_INSN (label);
7690 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7692 rtx epilogue_line_note = NULL_RTX;
7694 /* Locate the line number associated with the closing brace,
7695 if we can find one. */
7696 for (seq = get_last_insn ();
7697 seq && ! active_insn_p (seq);
7698 seq = PREV_INSN (seq))
7699 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7701 epilogue_line_note = seq;
7705 for (e = last->pred; e; e = e_next)
7707 basic_block bb = e->src;
7710 e_next = e->pred_next;
7711 if (bb == ENTRY_BLOCK_PTR)
7715 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7718 /* If we have an unconditional jump, we can replace that
7719 with a simple return instruction. */
7720 if (simplejump_p (jump))
7722 emit_return_into_block (bb, epilogue_line_note);
7726 /* If we have a conditional jump, we can try to replace
7727 that with a conditional return instruction. */
7728 else if (condjump_p (jump))
7730 if (! redirect_jump (jump, 0, 0))
7733 /* If this block has only one successor, it both jumps
7734 and falls through to the fallthru block, so we can't
7736 if (bb->succ->succ_next == NULL)
7742 /* Fix up the CFG for the successful change we just made. */
7743 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7746 /* Emit a return insn for the exit fallthru block. Whether
7747 this is still reachable will be determined later. */
7749 emit_barrier_after (last->end);
7750 emit_return_into_block (last, epilogue_line_note);
7751 epilogue_end = last->end;
7752 last->succ->flags &= ~EDGE_FALLTHRU;
7757 #ifdef HAVE_epilogue
7760 /* Find the edge that falls through to EXIT. Other edges may exist
7761 due to RETURN instructions, but those don't need epilogues.
7762 There really shouldn't be a mixture -- either all should have
7763 been converted or none, however... */
7765 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7766 if (e->flags & EDGE_FALLTHRU)
7772 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
7774 seq = gen_epilogue ();
7776 #ifdef INCOMING_RETURN_ADDR_RTX
7777 /* If this function returns with the stack depressed and we can support
7778 it, massage the epilogue to actually do that. */
7779 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7780 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7781 seq = keep_stack_depressed (seq);
7784 emit_jump_insn (seq);
7786 /* Retain a map of the epilogue insns. */
7787 record_insns (seq, &epilogue);
7792 insert_insn_on_edge (seq, e);
7799 commit_edge_insertions ();
7801 #ifdef HAVE_sibcall_epilogue
7802 /* Emit sibling epilogues before any sibling call sites. */
7803 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7805 basic_block bb = e->src;
7810 if (GET_CODE (insn) != CALL_INSN
7811 || ! SIBLING_CALL_P (insn))
7815 emit_insn (gen_sibcall_epilogue ());
7819 /* Retain a map of the epilogue insns. Used in life analysis to
7820 avoid getting rid of sibcall epilogue insns. Do this before we
7821 actually emit the sequence. */
7822 record_insns (seq, &sibcall_epilogue);
7824 i = PREV_INSN (insn);
7825 newinsn = emit_insn_before (seq, insn);
7829 #ifdef HAVE_prologue
7834 /* GDB handles `break f' by setting a breakpoint on the first
7835 line note after the prologue. Which means (1) that if
7836 there are line number notes before where we inserted the
7837 prologue we should move them, and (2) we should generate a
7838 note before the end of the first basic block, if there isn't
7841 ??? This behavior is completely broken when dealing with
7842 multiple entry functions. We simply place the note always
7843 into first basic block and let alternate entry points
7847 for (insn = prologue_end; insn; insn = prev)
7849 prev = PREV_INSN (insn);
7850 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7852 /* Note that we cannot reorder the first insn in the
7853 chain, since rest_of_compilation relies on that
7854 remaining constant. */
7857 reorder_insns (insn, insn, prologue_end);
7861 /* Find the last line number note in the first block. */
7862 for (insn = ENTRY_BLOCK_PTR->next_bb->end;
7863 insn != prologue_end && insn;
7864 insn = PREV_INSN (insn))
7865 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7868 /* If we didn't find one, make a copy of the first line number
7872 for (insn = next_active_insn (prologue_end);
7874 insn = PREV_INSN (insn))
7875 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7877 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7878 NOTE_LINE_NUMBER (insn),
7885 #ifdef HAVE_epilogue
7890 /* Similarly, move any line notes that appear after the epilogue.
7891 There is no need, however, to be quite so anal about the existence
7893 for (insn = epilogue_end; insn; insn = next)
7895 next = NEXT_INSN (insn);
7896 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7897 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7903 /* Reposition the prologue-end and epilogue-begin notes after instruction
7904 scheduling and delayed branch scheduling. */
7907 reposition_prologue_and_epilogue_notes (f)
7908 rtx f ATTRIBUTE_UNUSED;
7910 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7911 rtx insn, last, note;
7914 if ((len = VARRAY_SIZE (prologue)) > 0)
7918 /* Scan from the beginning until we reach the last prologue insn.
7919 We apparently can't depend on basic_block_{head,end} after
7921 for (insn = f; insn; insn = NEXT_INSN (insn))
7923 if (GET_CODE (insn) == NOTE)
7925 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7928 else if (contains (insn, prologue))
7938 /* Find the prologue-end note if we haven't already, and
7939 move it to just after the last prologue insn. */
7942 for (note = last; (note = NEXT_INSN (note));)
7943 if (GET_CODE (note) == NOTE
7944 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7948 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7949 if (GET_CODE (last) == CODE_LABEL)
7950 last = NEXT_INSN (last);
7951 reorder_insns (note, note, last);
7955 if ((len = VARRAY_SIZE (epilogue)) > 0)
7959 /* Scan from the end until we reach the first epilogue insn.
7960 We apparently can't depend on basic_block_{head,end} after
7962 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
7964 if (GET_CODE (insn) == NOTE)
7966 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7969 else if (contains (insn, epilogue))
7979 /* Find the epilogue-begin note if we haven't already, and
7980 move it to just before the first epilogue insn. */
7983 for (note = insn; (note = PREV_INSN (note));)
7984 if (GET_CODE (note) == NOTE
7985 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7989 if (PREV_INSN (last) != note)
7990 reorder_insns (note, note, PREV_INSN (last));
7993 #endif /* HAVE_prologue or HAVE_epilogue */
7996 /* Called once, at initialization, to initialize function.c. */
7999 init_function_once ()
8001 VARRAY_INT_INIT (prologue, 0, "prologue");
8002 VARRAY_INT_INIT (epilogue, 0, "epilogue");
8003 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
8006 #include "gt-function.h"