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))
3055 sub = force_operand (sub, NULL_RTX);
3056 if (! validate_change (insn, loc, sub, 0)
3057 && ! validate_replace_rtx (x, sub, insn))
3060 insns = get_insns ();
3062 emit_insn_before (insns, insn);
3066 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3068 rtx sub = XEXP (XEXP (x, 0), 0);
3072 if (!postponed_insns || XEXP (postponed_insns, 0) != insn)
3073 postponed_insns = alloc_INSN_LIST (insn, postponed_insns);
3077 if (GET_CODE (sub) == MEM)
3078 sub = adjust_address_nv (sub, GET_MODE (x), 0);
3079 else if (GET_CODE (sub) == REG
3080 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3082 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3084 int size_x, size_sub;
3088 /* When processing REG_NOTES look at the list of
3089 replacements done on the insn to find the register that X
3093 for (tem = purge_bitfield_addressof_replacements;
3095 tem = XEXP (XEXP (tem, 1), 1))
3096 if (rtx_equal_p (x, XEXP (tem, 0)))
3098 *loc = XEXP (XEXP (tem, 1), 0);
3102 /* See comment for purge_addressof_replacements. */
3103 for (tem = purge_addressof_replacements;
3105 tem = XEXP (XEXP (tem, 1), 1))
3106 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3108 rtx z = XEXP (XEXP (tem, 1), 0);
3110 if (GET_MODE (x) == GET_MODE (z)
3111 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3112 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3115 /* It can happen that the note may speak of things
3116 in a wider (or just different) mode than the
3117 code did. This is especially true of
3120 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3123 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3124 && (GET_MODE_SIZE (GET_MODE (x))
3125 > GET_MODE_SIZE (GET_MODE (z))))
3127 /* This can occur as a result in invalid
3128 pointer casts, e.g. float f; ...
3129 *(long long int *)&f.
3130 ??? We could emit a warning here, but
3131 without a line number that wouldn't be
3133 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3136 z = gen_lowpart (GET_MODE (x), z);
3142 /* Sometimes we may not be able to find the replacement. For
3143 example when the original insn was a MEM in a wider mode,
3144 and the note is part of a sign extension of a narrowed
3145 version of that MEM. Gcc testcase compile/990829-1.c can
3146 generate an example of this situation. Rather than complain
3147 we return false, which will prompt our caller to remove the
3152 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3153 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3155 /* Do not frob unchanging MEMs. If a later reference forces the
3156 pseudo to the stack, we can wind up with multiple writes to
3157 an unchanging memory, which is invalid. */
3158 if (RTX_UNCHANGING_P (x) && size_x != size_sub)
3161 /* Don't even consider working with paradoxical subregs,
3162 or the moral equivalent seen here. */
3163 else if (size_x <= size_sub
3164 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3166 /* Do a bitfield insertion to mirror what would happen
3173 rtx p = PREV_INSN (insn);
3176 val = gen_reg_rtx (GET_MODE (x));
3177 if (! validate_change (insn, loc, val, 0))
3179 /* Discard the current sequence and put the
3180 ADDRESSOF on stack. */
3186 emit_insn_before (seq, insn);
3187 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3191 store_bit_field (sub, size_x, 0, GET_MODE (x),
3192 val, GET_MODE_SIZE (GET_MODE (sub)));
3194 /* Make sure to unshare any shared rtl that store_bit_field
3195 might have created. */
3196 unshare_all_rtl_again (get_insns ());
3200 p = emit_insn_after (seq, insn);
3201 if (NEXT_INSN (insn))
3202 compute_insns_for_mem (NEXT_INSN (insn),
3203 p ? NEXT_INSN (p) : NULL_RTX,
3208 rtx p = PREV_INSN (insn);
3211 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3212 GET_MODE (x), GET_MODE (x),
3213 GET_MODE_SIZE (GET_MODE (sub)));
3215 if (! validate_change (insn, loc, val, 0))
3217 /* Discard the current sequence and put the
3218 ADDRESSOF on stack. */
3225 emit_insn_before (seq, insn);
3226 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3230 /* Remember the replacement so that the same one can be done
3231 on the REG_NOTES. */
3232 purge_bitfield_addressof_replacements
3233 = gen_rtx_EXPR_LIST (VOIDmode, x,
3236 purge_bitfield_addressof_replacements));
3238 /* We replaced with a reg -- all done. */
3243 else if (validate_change (insn, loc, sub, 0))
3245 /* Remember the replacement so that the same one can be done
3246 on the REG_NOTES. */
3247 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3251 for (tem = purge_addressof_replacements;
3253 tem = XEXP (XEXP (tem, 1), 1))
3254 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3256 XEXP (XEXP (tem, 1), 0) = sub;
3259 purge_addressof_replacements
3260 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3261 gen_rtx_EXPR_LIST (VOIDmode, sub,
3262 purge_addressof_replacements));
3270 /* Scan all subexpressions. */
3271 fmt = GET_RTX_FORMAT (code);
3272 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3275 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0,
3277 else if (*fmt == 'E')
3278 for (j = 0; j < XVECLEN (x, i); j++)
3279 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0,
3286 /* Return a hash value for K, a REG. */
3289 insns_for_mem_hash (k)
3292 /* Use the address of the key for the hash value. */
3293 struct insns_for_mem_entry *m = (struct insns_for_mem_entry *) k;
3294 return htab_hash_pointer (m->key);
3297 /* Return nonzero if K1 and K2 (two REGs) are the same. */
3300 insns_for_mem_comp (k1, k2)
3304 struct insns_for_mem_entry *m1 = (struct insns_for_mem_entry *) k1;
3305 struct insns_for_mem_entry *m2 = (struct insns_for_mem_entry *) k2;
3306 return m1->key == m2->key;
3309 struct insns_for_mem_walk_info
3311 /* The hash table that we are using to record which INSNs use which
3315 /* The INSN we are currently processing. */
3318 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3319 to find the insns that use the REGs in the ADDRESSOFs. */
3323 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3324 that might be used in an ADDRESSOF expression, record this INSN in
3325 the hash table given by DATA (which is really a pointer to an
3326 insns_for_mem_walk_info structure). */
3329 insns_for_mem_walk (r, data)
3333 struct insns_for_mem_walk_info *ifmwi
3334 = (struct insns_for_mem_walk_info *) data;
3335 struct insns_for_mem_entry tmp;
3336 tmp.insns = NULL_RTX;
3338 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3339 && GET_CODE (XEXP (*r, 0)) == REG)
3342 tmp.key = XEXP (*r, 0);
3343 e = htab_find_slot (ifmwi->ht, &tmp, INSERT);
3346 *e = ggc_alloc (sizeof (tmp));
3347 memcpy (*e, &tmp, sizeof (tmp));
3350 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3352 struct insns_for_mem_entry *ifme;
3354 ifme = (struct insns_for_mem_entry *) htab_find (ifmwi->ht, &tmp);
3356 /* If we have not already recorded this INSN, do so now. Since
3357 we process the INSNs in order, we know that if we have
3358 recorded it it must be at the front of the list. */
3359 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3360 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3367 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3368 which REGs in HT. */
3371 compute_insns_for_mem (insns, last_insn, ht)
3377 struct insns_for_mem_walk_info ifmwi;
3380 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3381 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3385 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3389 /* Helper function for purge_addressof called through for_each_rtx.
3390 Returns true iff the rtl is an ADDRESSOF. */
3393 is_addressof (rtl, data)
3395 void *data ATTRIBUTE_UNUSED;
3397 return GET_CODE (*rtl) == ADDRESSOF;
3400 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3401 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3405 purge_addressof (insns)
3411 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3412 requires a fixup pass over the instruction stream to correct
3413 INSNs that depended on the REG being a REG, and not a MEM. But,
3414 these fixup passes are slow. Furthermore, most MEMs are not
3415 mentioned in very many instructions. So, we speed up the process
3416 by pre-calculating which REGs occur in which INSNs; that allows
3417 us to perform the fixup passes much more quickly. */
3418 ht = htab_create_ggc (1000, insns_for_mem_hash, insns_for_mem_comp, NULL);
3419 compute_insns_for_mem (insns, NULL_RTX, ht);
3421 postponed_insns = NULL;
3423 for (insn = insns; insn; insn = NEXT_INSN (insn))
3426 if (! purge_addressof_1 (&PATTERN (insn), insn,
3427 asm_noperands (PATTERN (insn)) > 0, 0, 1, ht))
3428 /* If we could not replace the ADDRESSOFs in the insn,
3429 something is wrong. */
3432 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, 0, ht))
3434 /* If we could not replace the ADDRESSOFs in the insn's notes,
3435 we can just remove the offending notes instead. */
3438 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3440 /* If we find a REG_RETVAL note then the insn is a libcall.
3441 Such insns must have REG_EQUAL notes as well, in order
3442 for later passes of the compiler to work. So it is not
3443 safe to delete the notes here, and instead we abort. */
3444 if (REG_NOTE_KIND (note) == REG_RETVAL)
3446 if (for_each_rtx (¬e, is_addressof, NULL))
3447 remove_note (insn, note);
3452 /* Process the postponed insns. */
3453 while (postponed_insns)
3455 insn = XEXP (postponed_insns, 0);
3456 tmp = postponed_insns;
3457 postponed_insns = XEXP (postponed_insns, 1);
3458 free_INSN_LIST_node (tmp);
3460 if (! purge_addressof_1 (&PATTERN (insn), insn,
3461 asm_noperands (PATTERN (insn)) > 0, 0, 0, ht))
3466 purge_bitfield_addressof_replacements = 0;
3467 purge_addressof_replacements = 0;
3469 /* REGs are shared. purge_addressof will destructively replace a REG
3470 with a MEM, which creates shared MEMs.
3472 Unfortunately, the children of put_reg_into_stack assume that MEMs
3473 referring to the same stack slot are shared (fixup_var_refs and
3474 the associated hash table code).
3476 So, we have to do another unsharing pass after we have flushed any
3477 REGs that had their address taken into the stack.
3479 It may be worth tracking whether or not we converted any REGs into
3480 MEMs to avoid this overhead when it is not needed. */
3481 unshare_all_rtl_again (get_insns ());
3484 /* Convert a SET of a hard subreg to a set of the appropriate hard
3485 register. A subroutine of purge_hard_subreg_sets. */
3488 purge_single_hard_subreg_set (pattern)
3491 rtx reg = SET_DEST (pattern);
3492 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3495 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3496 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3498 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3499 GET_MODE (SUBREG_REG (reg)),
3502 reg = SUBREG_REG (reg);
3506 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3508 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3509 SET_DEST (pattern) = reg;
3513 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3514 only such SETs that we expect to see are those left in because
3515 integrate can't handle sets of parts of a return value register.
3517 We don't use alter_subreg because we only want to eliminate subregs
3518 of hard registers. */
3521 purge_hard_subreg_sets (insn)
3524 for (; insn; insn = NEXT_INSN (insn))
3528 rtx pattern = PATTERN (insn);
3529 switch (GET_CODE (pattern))
3532 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3533 purge_single_hard_subreg_set (pattern);
3538 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3540 rtx inner_pattern = XVECEXP (pattern, 0, j);
3541 if (GET_CODE (inner_pattern) == SET
3542 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3543 purge_single_hard_subreg_set (inner_pattern);
3554 /* Pass through the INSNS of function FNDECL and convert virtual register
3555 references to hard register references. */
3558 instantiate_virtual_regs (fndecl, insns)
3565 /* Compute the offsets to use for this function. */
3566 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3567 var_offset = STARTING_FRAME_OFFSET;
3568 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3569 out_arg_offset = STACK_POINTER_OFFSET;
3570 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3572 /* Scan all variables and parameters of this function. For each that is
3573 in memory, instantiate all virtual registers if the result is a valid
3574 address. If not, we do it later. That will handle most uses of virtual
3575 regs on many machines. */
3576 instantiate_decls (fndecl, 1);
3578 /* Initialize recognition, indicating that volatile is OK. */
3581 /* Scan through all the insns, instantiating every virtual register still
3583 for (insn = insns; insn; insn = NEXT_INSN (insn))
3584 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3585 || GET_CODE (insn) == CALL_INSN)
3587 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3588 if (INSN_DELETED_P (insn))
3590 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3591 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3592 if (GET_CODE (insn) == CALL_INSN)
3593 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3596 /* Past this point all ASM statements should match. Verify that
3597 to avoid failures later in the compilation process. */
3598 if (asm_noperands (PATTERN (insn)) >= 0
3599 && ! check_asm_operands (PATTERN (insn)))
3600 instantiate_virtual_regs_lossage (insn);
3603 /* Instantiate the stack slots for the parm registers, for later use in
3604 addressof elimination. */
3605 for (i = 0; i < max_parm_reg; ++i)
3606 if (parm_reg_stack_loc[i])
3607 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3609 /* Now instantiate the remaining register equivalences for debugging info.
3610 These will not be valid addresses. */
3611 instantiate_decls (fndecl, 0);
3613 /* Indicate that, from now on, assign_stack_local should use
3614 frame_pointer_rtx. */
3615 virtuals_instantiated = 1;
3618 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3619 all virtual registers in their DECL_RTL's.
3621 If VALID_ONLY, do this only if the resulting address is still valid.
3622 Otherwise, always do it. */
3625 instantiate_decls (fndecl, valid_only)
3631 /* Process all parameters of the function. */
3632 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3634 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3635 HOST_WIDE_INT size_rtl;
3637 instantiate_decl (DECL_RTL (decl), size, valid_only);
3639 /* If the parameter was promoted, then the incoming RTL mode may be
3640 larger than the declared type size. We must use the larger of
3642 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3643 size = MAX (size_rtl, size);
3644 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3647 /* Now process all variables defined in the function or its subblocks. */
3648 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3651 /* Subroutine of instantiate_decls: Process all decls in the given
3652 BLOCK node and all its subblocks. */
3655 instantiate_decls_1 (let, valid_only)
3661 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3662 if (DECL_RTL_SET_P (t))
3663 instantiate_decl (DECL_RTL (t),
3664 int_size_in_bytes (TREE_TYPE (t)),
3667 /* Process all subblocks. */
3668 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3669 instantiate_decls_1 (t, valid_only);
3672 /* Subroutine of the preceding procedures: Given RTL representing a
3673 decl and the size of the object, do any instantiation required.
3675 If VALID_ONLY is nonzero, it means that the RTL should only be
3676 changed if the new address is valid. */
3679 instantiate_decl (x, size, valid_only)
3684 enum machine_mode mode;
3687 /* If this is not a MEM, no need to do anything. Similarly if the
3688 address is a constant or a register that is not a virtual register. */
3690 if (x == 0 || GET_CODE (x) != MEM)
3694 if (CONSTANT_P (addr)
3695 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3696 || (GET_CODE (addr) == REG
3697 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3698 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3701 /* If we should only do this if the address is valid, copy the address.
3702 We need to do this so we can undo any changes that might make the
3703 address invalid. This copy is unfortunate, but probably can't be
3707 addr = copy_rtx (addr);
3709 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3711 if (valid_only && size >= 0)
3713 unsigned HOST_WIDE_INT decl_size = size;
3715 /* Now verify that the resulting address is valid for every integer or
3716 floating-point mode up to and including SIZE bytes long. We do this
3717 since the object might be accessed in any mode and frame addresses
3720 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3721 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3722 mode = GET_MODE_WIDER_MODE (mode))
3723 if (! memory_address_p (mode, addr))
3726 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3727 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3728 mode = GET_MODE_WIDER_MODE (mode))
3729 if (! memory_address_p (mode, addr))
3733 /* Put back the address now that we have updated it and we either know
3734 it is valid or we don't care whether it is valid. */
3739 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3740 is a virtual register, return the equivalent hard register and set the
3741 offset indirectly through the pointer. Otherwise, return 0. */
3744 instantiate_new_reg (x, poffset)
3746 HOST_WIDE_INT *poffset;
3749 HOST_WIDE_INT offset;
3751 if (x == virtual_incoming_args_rtx)
3752 new = arg_pointer_rtx, offset = in_arg_offset;
3753 else if (x == virtual_stack_vars_rtx)
3754 new = frame_pointer_rtx, offset = var_offset;
3755 else if (x == virtual_stack_dynamic_rtx)
3756 new = stack_pointer_rtx, offset = dynamic_offset;
3757 else if (x == virtual_outgoing_args_rtx)
3758 new = stack_pointer_rtx, offset = out_arg_offset;
3759 else if (x == virtual_cfa_rtx)
3760 new = arg_pointer_rtx, offset = cfa_offset;
3769 /* Called when instantiate_virtual_regs has failed to update the instruction.
3770 Usually this means that non-matching instruction has been emit, however for
3771 asm statements it may be the problem in the constraints. */
3773 instantiate_virtual_regs_lossage (insn)
3776 if (asm_noperands (PATTERN (insn)) >= 0)
3778 error_for_asm (insn, "impossible constraint in `asm'");
3784 /* Given a pointer to a piece of rtx and an optional pointer to the
3785 containing object, instantiate any virtual registers present in it.
3787 If EXTRA_INSNS, we always do the replacement and generate
3788 any extra insns before OBJECT. If it zero, we do nothing if replacement
3791 Return 1 if we either had nothing to do or if we were able to do the
3792 needed replacement. Return 0 otherwise; we only return zero if
3793 EXTRA_INSNS is zero.
3795 We first try some simple transformations to avoid the creation of extra
3799 instantiate_virtual_regs_1 (loc, object, extra_insns)
3807 HOST_WIDE_INT offset = 0;
3813 /* Re-start here to avoid recursion in common cases. */
3820 /* We may have detected and deleted invalid asm statements. */
3821 if (object && INSN_P (object) && INSN_DELETED_P (object))
3824 code = GET_CODE (x);
3826 /* Check for some special cases. */
3844 /* We are allowed to set the virtual registers. This means that
3845 the actual register should receive the source minus the
3846 appropriate offset. This is used, for example, in the handling
3847 of non-local gotos. */
3848 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3850 rtx src = SET_SRC (x);
3852 /* We are setting the register, not using it, so the relevant
3853 offset is the negative of the offset to use were we using
3856 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3858 /* The only valid sources here are PLUS or REG. Just do
3859 the simplest possible thing to handle them. */
3860 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3862 instantiate_virtual_regs_lossage (object);
3867 if (GET_CODE (src) != REG)
3868 temp = force_operand (src, NULL_RTX);
3871 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3875 emit_insn_before (seq, object);
3878 if (! validate_change (object, &SET_SRC (x), temp, 0)
3880 instantiate_virtual_regs_lossage (object);
3885 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3890 /* Handle special case of virtual register plus constant. */
3891 if (CONSTANT_P (XEXP (x, 1)))
3893 rtx old, new_offset;
3895 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3896 if (GET_CODE (XEXP (x, 0)) == PLUS)
3898 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3900 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3902 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3911 #ifdef POINTERS_EXTEND_UNSIGNED
3912 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3913 we can commute the PLUS and SUBREG because pointers into the
3914 frame are well-behaved. */
3915 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3916 && GET_CODE (XEXP (x, 1)) == CONST_INT
3918 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3920 && validate_change (object, loc,
3921 plus_constant (gen_lowpart (ptr_mode,
3924 + INTVAL (XEXP (x, 1))),
3928 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3930 /* We know the second operand is a constant. Unless the
3931 first operand is a REG (which has been already checked),
3932 it needs to be checked. */
3933 if (GET_CODE (XEXP (x, 0)) != REG)
3941 new_offset = plus_constant (XEXP (x, 1), offset);
3943 /* If the new constant is zero, try to replace the sum with just
3945 if (new_offset == const0_rtx
3946 && validate_change (object, loc, new, 0))
3949 /* Next try to replace the register and new offset.
3950 There are two changes to validate here and we can't assume that
3951 in the case of old offset equals new just changing the register
3952 will yield a valid insn. In the interests of a little efficiency,
3953 however, we only call validate change once (we don't queue up the
3954 changes and then call apply_change_group). */
3958 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3959 : (XEXP (x, 0) = new,
3960 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3968 /* Otherwise copy the new constant into a register and replace
3969 constant with that register. */
3970 temp = gen_reg_rtx (Pmode);
3972 if (validate_change (object, &XEXP (x, 1), temp, 0))
3973 emit_insn_before (gen_move_insn (temp, new_offset), object);
3976 /* If that didn't work, replace this expression with a
3977 register containing the sum. */
3980 new = gen_rtx_PLUS (Pmode, new, new_offset);
3983 temp = force_operand (new, NULL_RTX);
3987 emit_insn_before (seq, object);
3988 if (! validate_change (object, loc, temp, 0)
3989 && ! validate_replace_rtx (x, temp, object))
3991 instantiate_virtual_regs_lossage (object);
4000 /* Fall through to generic two-operand expression case. */
4006 case DIV: case UDIV:
4007 case MOD: case UMOD:
4008 case AND: case IOR: case XOR:
4009 case ROTATERT: case ROTATE:
4010 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
4012 case GE: case GT: case GEU: case GTU:
4013 case LE: case LT: case LEU: case LTU:
4014 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
4015 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
4020 /* Most cases of MEM that convert to valid addresses have already been
4021 handled by our scan of decls. The only special handling we
4022 need here is to make a copy of the rtx to ensure it isn't being
4023 shared if we have to change it to a pseudo.
4025 If the rtx is a simple reference to an address via a virtual register,
4026 it can potentially be shared. In such cases, first try to make it
4027 a valid address, which can also be shared. Otherwise, copy it and
4030 First check for common cases that need no processing. These are
4031 usually due to instantiation already being done on a previous instance
4035 if (CONSTANT_ADDRESS_P (temp)
4036 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4037 || temp == arg_pointer_rtx
4039 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4040 || temp == hard_frame_pointer_rtx
4042 || temp == frame_pointer_rtx)
4045 if (GET_CODE (temp) == PLUS
4046 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4047 && (XEXP (temp, 0) == frame_pointer_rtx
4048 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4049 || XEXP (temp, 0) == hard_frame_pointer_rtx
4051 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4052 || XEXP (temp, 0) == arg_pointer_rtx
4057 if (temp == virtual_stack_vars_rtx
4058 || temp == virtual_incoming_args_rtx
4059 || (GET_CODE (temp) == PLUS
4060 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4061 && (XEXP (temp, 0) == virtual_stack_vars_rtx
4062 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
4064 /* This MEM may be shared. If the substitution can be done without
4065 the need to generate new pseudos, we want to do it in place
4066 so all copies of the shared rtx benefit. The call below will
4067 only make substitutions if the resulting address is still
4070 Note that we cannot pass X as the object in the recursive call
4071 since the insn being processed may not allow all valid
4072 addresses. However, if we were not passed on object, we can
4073 only modify X without copying it if X will have a valid
4076 ??? Also note that this can still lose if OBJECT is an insn that
4077 has less restrictions on an address that some other insn.
4078 In that case, we will modify the shared address. This case
4079 doesn't seem very likely, though. One case where this could
4080 happen is in the case of a USE or CLOBBER reference, but we
4081 take care of that below. */
4083 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
4084 object ? object : x, 0))
4087 /* Otherwise make a copy and process that copy. We copy the entire
4088 RTL expression since it might be a PLUS which could also be
4090 *loc = x = copy_rtx (x);
4093 /* Fall through to generic unary operation case. */
4096 case STRICT_LOW_PART:
4098 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4099 case SIGN_EXTEND: case ZERO_EXTEND:
4100 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4101 case FLOAT: case FIX:
4102 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4107 case POPCOUNT: case PARITY:
4108 /* These case either have just one operand or we know that we need not
4109 check the rest of the operands. */
4115 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4116 go ahead and make the invalid one, but do it to a copy. For a REG,
4117 just make the recursive call, since there's no chance of a problem. */
4119 if ((GET_CODE (XEXP (x, 0)) == MEM
4120 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4122 || (GET_CODE (XEXP (x, 0)) == REG
4123 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4126 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4131 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4132 in front of this insn and substitute the temporary. */
4133 if ((new = instantiate_new_reg (x, &offset)) != 0)
4135 temp = plus_constant (new, offset);
4136 if (!validate_change (object, loc, temp, 0))
4142 temp = force_operand (temp, NULL_RTX);
4146 emit_insn_before (seq, object);
4147 if (! validate_change (object, loc, temp, 0)
4148 && ! validate_replace_rtx (x, temp, object))
4149 instantiate_virtual_regs_lossage (object);
4156 if (GET_CODE (XEXP (x, 0)) == REG)
4159 else if (GET_CODE (XEXP (x, 0)) == MEM)
4161 /* If we have a (addressof (mem ..)), do any instantiation inside
4162 since we know we'll be making the inside valid when we finally
4163 remove the ADDRESSOF. */
4164 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4173 /* Scan all subexpressions. */
4174 fmt = GET_RTX_FORMAT (code);
4175 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4178 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4181 else if (*fmt == 'E')
4182 for (j = 0; j < XVECLEN (x, i); j++)
4183 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4190 /* Optimization: assuming this function does not receive nonlocal gotos,
4191 delete the handlers for such, as well as the insns to establish
4192 and disestablish them. */
4198 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4200 /* Delete the handler by turning off the flag that would
4201 prevent jump_optimize from deleting it.
4202 Also permit deletion of the nonlocal labels themselves
4203 if nothing local refers to them. */
4204 if (GET_CODE (insn) == CODE_LABEL)
4208 LABEL_PRESERVE_P (insn) = 0;
4210 /* Remove it from the nonlocal_label list, to avoid confusing
4212 for (t = nonlocal_labels, last_t = 0; t;
4213 last_t = t, t = TREE_CHAIN (t))
4214 if (DECL_RTL (TREE_VALUE (t)) == insn)
4219 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4221 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4224 if (GET_CODE (insn) == INSN)
4228 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4229 if (reg_mentioned_p (t, PATTERN (insn)))
4235 || (nonlocal_goto_stack_level != 0
4236 && reg_mentioned_p (nonlocal_goto_stack_level,
4238 delete_related_insns (insn);
4243 /* Return the first insn following those generated by `assign_parms'. */
4246 get_first_nonparm_insn ()
4249 return NEXT_INSN (last_parm_insn);
4250 return get_insns ();
4253 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4254 This means a type for which function calls must pass an address to the
4255 function or get an address back from the function.
4256 EXP may be a type node or an expression (whose type is tested). */
4259 aggregate_value_p (exp)
4262 int i, regno, nregs;
4265 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4267 if (TREE_CODE (type) == VOID_TYPE)
4269 if (RETURN_IN_MEMORY (type))
4271 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4272 and thus can't be returned in registers. */
4273 if (TREE_ADDRESSABLE (type))
4275 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4277 /* Make sure we have suitable call-clobbered regs to return
4278 the value in; if not, we must return it in memory. */
4279 reg = hard_function_value (type, 0, 0);
4281 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4283 if (GET_CODE (reg) != REG)
4286 regno = REGNO (reg);
4287 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4288 for (i = 0; i < nregs; i++)
4289 if (! call_used_regs[regno + i])
4294 /* Assign RTL expressions to the function's parameters.
4295 This may involve copying them into registers and using
4296 those registers as the RTL for them. */
4299 assign_parms (fndecl)
4305 CUMULATIVE_ARGS args_so_far;
4306 enum machine_mode promoted_mode, passed_mode;
4307 enum machine_mode nominal_mode, promoted_nominal_mode;
4309 /* Total space needed so far for args on the stack,
4310 given as a constant and a tree-expression. */
4311 struct args_size stack_args_size;
4312 tree fntype = TREE_TYPE (fndecl);
4313 tree fnargs = DECL_ARGUMENTS (fndecl);
4314 /* This is used for the arg pointer when referring to stack args. */
4315 rtx internal_arg_pointer;
4316 /* This is a dummy PARM_DECL that we used for the function result if
4317 the function returns a structure. */
4318 tree function_result_decl = 0;
4319 #ifdef SETUP_INCOMING_VARARGS
4320 int varargs_setup = 0;
4322 rtx conversion_insns = 0;
4323 struct args_size alignment_pad;
4325 /* Nonzero if function takes extra anonymous args.
4326 This means the last named arg must be on the stack
4327 right before the anonymous ones. */
4329 = (TYPE_ARG_TYPES (fntype) != 0
4330 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4331 != void_type_node));
4333 current_function_stdarg = stdarg;
4335 /* If the reg that the virtual arg pointer will be translated into is
4336 not a fixed reg or is the stack pointer, make a copy of the virtual
4337 arg pointer, and address parms via the copy. The frame pointer is
4338 considered fixed even though it is not marked as such.
4340 The second time through, simply use ap to avoid generating rtx. */
4342 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4343 || ! (fixed_regs[ARG_POINTER_REGNUM]
4344 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4345 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4347 internal_arg_pointer = virtual_incoming_args_rtx;
4348 current_function_internal_arg_pointer = internal_arg_pointer;
4350 stack_args_size.constant = 0;
4351 stack_args_size.var = 0;
4353 /* If struct value address is treated as the first argument, make it so. */
4354 if (aggregate_value_p (DECL_RESULT (fndecl))
4355 && ! current_function_returns_pcc_struct
4356 && struct_value_incoming_rtx == 0)
4358 tree type = build_pointer_type (TREE_TYPE (fntype));
4360 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4362 DECL_ARG_TYPE (function_result_decl) = type;
4363 TREE_CHAIN (function_result_decl) = fnargs;
4364 fnargs = function_result_decl;
4367 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4368 parm_reg_stack_loc = (rtx *) ggc_alloc_cleared (max_parm_reg * sizeof (rtx));
4370 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4371 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4373 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, fndecl);
4376 /* We haven't yet found an argument that we must push and pretend the
4378 current_function_pretend_args_size = 0;
4380 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4382 struct args_size stack_offset;
4383 struct args_size arg_size;
4384 int passed_pointer = 0;
4385 int did_conversion = 0;
4386 tree passed_type = DECL_ARG_TYPE (parm);
4387 tree nominal_type = TREE_TYPE (parm);
4389 int last_named = 0, named_arg;
4391 /* Set LAST_NAMED if this is last named arg before last
4397 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4398 if (DECL_NAME (tem))
4404 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4405 most machines, if this is a varargs/stdarg function, then we treat
4406 the last named arg as if it were anonymous too. */
4407 named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4409 if (TREE_TYPE (parm) == error_mark_node
4410 /* This can happen after weird syntax errors
4411 or if an enum type is defined among the parms. */
4412 || TREE_CODE (parm) != PARM_DECL
4413 || passed_type == NULL)
4415 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4416 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4417 TREE_USED (parm) = 1;
4421 /* Find mode of arg as it is passed, and mode of arg
4422 as it should be during execution of this function. */
4423 passed_mode = TYPE_MODE (passed_type);
4424 nominal_mode = TYPE_MODE (nominal_type);
4426 /* If the parm's mode is VOID, its value doesn't matter,
4427 and avoid the usual things like emit_move_insn that could crash. */
4428 if (nominal_mode == VOIDmode)
4430 SET_DECL_RTL (parm, const0_rtx);
4431 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4435 /* If the parm is to be passed as a transparent union, use the
4436 type of the first field for the tests below. We have already
4437 verified that the modes are the same. */
4438 if (DECL_TRANSPARENT_UNION (parm)
4439 || (TREE_CODE (passed_type) == UNION_TYPE
4440 && TYPE_TRANSPARENT_UNION (passed_type)))
4441 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4443 /* See if this arg was passed by invisible reference. It is if
4444 it is an object whose size depends on the contents of the
4445 object itself or if the machine requires these objects be passed
4448 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4449 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4450 || TREE_ADDRESSABLE (passed_type)
4451 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4452 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4453 passed_type, named_arg)
4457 passed_type = nominal_type = build_pointer_type (passed_type);
4459 passed_mode = nominal_mode = Pmode;
4461 /* See if the frontend wants to pass this by invisible reference. */
4462 else if (passed_type != nominal_type
4463 && POINTER_TYPE_P (passed_type)
4464 && TREE_TYPE (passed_type) == nominal_type)
4466 nominal_type = passed_type;
4468 passed_mode = nominal_mode = Pmode;
4471 promoted_mode = passed_mode;
4473 #ifdef PROMOTE_FUNCTION_ARGS
4474 /* Compute the mode in which the arg is actually extended to. */
4475 unsignedp = TREE_UNSIGNED (passed_type);
4476 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4479 /* Let machine desc say which reg (if any) the parm arrives in.
4480 0 means it arrives on the stack. */
4481 #ifdef FUNCTION_INCOMING_ARG
4482 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4483 passed_type, named_arg);
4485 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4486 passed_type, named_arg);
4489 if (entry_parm == 0)
4490 promoted_mode = passed_mode;
4492 #ifdef SETUP_INCOMING_VARARGS
4493 /* If this is the last named parameter, do any required setup for
4494 varargs or stdargs. We need to know about the case of this being an
4495 addressable type, in which case we skip the registers it
4496 would have arrived in.
4498 For stdargs, LAST_NAMED will be set for two parameters, the one that
4499 is actually the last named, and the dummy parameter. We only
4500 want to do this action once.
4502 Also, indicate when RTL generation is to be suppressed. */
4503 if (last_named && !varargs_setup)
4505 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4506 current_function_pretend_args_size, 0);
4511 /* Determine parm's home in the stack,
4512 in case it arrives in the stack or we should pretend it did.
4514 Compute the stack position and rtx where the argument arrives
4517 There is one complexity here: If this was a parameter that would
4518 have been passed in registers, but wasn't only because it is
4519 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4520 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4521 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4522 0 as it was the previous time. */
4524 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4525 locate_and_pad_parm (promoted_mode, passed_type,
4526 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4529 #ifdef FUNCTION_INCOMING_ARG
4530 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4532 pretend_named) != 0,
4534 FUNCTION_ARG (args_so_far, promoted_mode,
4536 pretend_named) != 0,
4539 fndecl, &stack_args_size, &stack_offset, &arg_size,
4543 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4545 if (offset_rtx == const0_rtx)
4546 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4548 stack_parm = gen_rtx_MEM (promoted_mode,
4549 gen_rtx_PLUS (Pmode,
4550 internal_arg_pointer,
4553 set_mem_attributes (stack_parm, parm, 1);
4555 /* Set also REG_ATTRS if parameter was passed in a register. */
4557 set_reg_attrs_for_parm (entry_parm, stack_parm);
4560 /* If this parameter was passed both in registers and in the stack,
4561 use the copy on the stack. */
4562 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4565 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4566 /* If this parm was passed part in regs and part in memory,
4567 pretend it arrived entirely in memory
4568 by pushing the register-part onto the stack.
4570 In the special case of a DImode or DFmode that is split,
4571 we could put it together in a pseudoreg directly,
4572 but for now that's not worth bothering with. */
4576 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4577 passed_type, named_arg);
4581 #if defined (REG_PARM_STACK_SPACE) && !defined (MAYBE_REG_PARM_STACK_SPACE)
4582 /* When REG_PARM_STACK_SPACE is nonzero, stack space for
4583 split parameters was allocated by our caller, so we
4584 won't be pushing it in the prolog. */
4585 if (REG_PARM_STACK_SPACE (fndecl) == 0)
4587 current_function_pretend_args_size
4588 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4589 / (PARM_BOUNDARY / BITS_PER_UNIT)
4590 * (PARM_BOUNDARY / BITS_PER_UNIT));
4592 /* Handle calls that pass values in multiple non-contiguous
4593 locations. The Irix 6 ABI has examples of this. */
4594 if (GET_CODE (entry_parm) == PARALLEL)
4595 emit_group_store (validize_mem (stack_parm), entry_parm,
4596 int_size_in_bytes (TREE_TYPE (parm)));
4599 move_block_from_reg (REGNO (entry_parm),
4600 validize_mem (stack_parm), nregs,
4601 int_size_in_bytes (TREE_TYPE (parm)));
4603 entry_parm = stack_parm;
4608 /* If we didn't decide this parm came in a register,
4609 by default it came on the stack. */
4610 if (entry_parm == 0)
4611 entry_parm = stack_parm;
4613 /* Record permanently how this parm was passed. */
4614 DECL_INCOMING_RTL (parm) = entry_parm;
4616 /* If there is actually space on the stack for this parm,
4617 count it in stack_args_size; otherwise set stack_parm to 0
4618 to indicate there is no preallocated stack slot for the parm. */
4620 if (entry_parm == stack_parm
4621 || (GET_CODE (entry_parm) == PARALLEL
4622 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4623 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4624 /* On some machines, even if a parm value arrives in a register
4625 there is still an (uninitialized) stack slot allocated for it.
4627 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4628 whether this parameter already has a stack slot allocated,
4629 because an arg block exists only if current_function_args_size
4630 is larger than some threshold, and we haven't calculated that
4631 yet. So, for now, we just assume that stack slots never exist
4633 || REG_PARM_STACK_SPACE (fndecl) > 0
4637 stack_args_size.constant += arg_size.constant;
4639 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4642 /* No stack slot was pushed for this parm. */
4645 /* Update info on where next arg arrives in registers. */
4647 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4648 passed_type, named_arg);
4650 /* If we can't trust the parm stack slot to be aligned enough
4651 for its ultimate type, don't use that slot after entry.
4652 We'll make another stack slot, if we need one. */
4654 unsigned int thisparm_boundary
4655 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4657 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4661 /* If parm was passed in memory, and we need to convert it on entry,
4662 don't store it back in that same slot. */
4664 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4667 /* When an argument is passed in multiple locations, we can't
4668 make use of this information, but we can save some copying if
4669 the whole argument is passed in a single register. */
4670 if (GET_CODE (entry_parm) == PARALLEL
4671 && nominal_mode != BLKmode && passed_mode != BLKmode)
4673 int i, len = XVECLEN (entry_parm, 0);
4675 for (i = 0; i < len; i++)
4676 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4677 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4678 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4680 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4682 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4683 DECL_INCOMING_RTL (parm) = entry_parm;
4688 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4689 in the mode in which it arrives.
4690 STACK_PARM is an RTX for a stack slot where the parameter can live
4691 during the function (in case we want to put it there).
4692 STACK_PARM is 0 if no stack slot was pushed for it.
4694 Now output code if necessary to convert ENTRY_PARM to
4695 the type in which this function declares it,
4696 and store that result in an appropriate place,
4697 which may be a pseudo reg, may be STACK_PARM,
4698 or may be a local stack slot if STACK_PARM is 0.
4700 Set DECL_RTL to that place. */
4702 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4704 /* If a BLKmode arrives in registers, copy it to a stack slot.
4705 Handle calls that pass values in multiple non-contiguous
4706 locations. The Irix 6 ABI has examples of this. */
4707 if (GET_CODE (entry_parm) == REG
4708 || GET_CODE (entry_parm) == PARALLEL)
4711 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4714 /* Note that we will be storing an integral number of words.
4715 So we have to be careful to ensure that we allocate an
4716 integral number of words. We do this below in the
4717 assign_stack_local if space was not allocated in the argument
4718 list. If it was, this will not work if PARM_BOUNDARY is not
4719 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4720 if it becomes a problem. */
4722 if (stack_parm == 0)
4725 = assign_stack_local (GET_MODE (entry_parm),
4727 set_mem_attributes (stack_parm, parm, 1);
4730 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4733 /* Handle calls that pass values in multiple non-contiguous
4734 locations. The Irix 6 ABI has examples of this. */
4735 if (GET_CODE (entry_parm) == PARALLEL)
4736 emit_group_store (validize_mem (stack_parm), entry_parm,
4737 int_size_in_bytes (TREE_TYPE (parm)));
4739 move_block_from_reg (REGNO (entry_parm),
4740 validize_mem (stack_parm),
4741 size_stored / UNITS_PER_WORD,
4742 int_size_in_bytes (TREE_TYPE (parm)));
4744 SET_DECL_RTL (parm, stack_parm);
4746 else if (! ((! optimize
4747 && ! DECL_REGISTER (parm))
4748 || TREE_SIDE_EFFECTS (parm)
4749 /* If -ffloat-store specified, don't put explicit
4750 float variables into registers. */
4751 || (flag_float_store
4752 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4753 /* Always assign pseudo to structure return or item passed
4754 by invisible reference. */
4755 || passed_pointer || parm == function_result_decl)
4757 /* Store the parm in a pseudoregister during the function, but we
4758 may need to do it in a wider mode. */
4761 unsigned int regno, regnoi = 0, regnor = 0;
4763 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4765 promoted_nominal_mode
4766 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4768 parmreg = gen_reg_rtx (promoted_nominal_mode);
4769 mark_user_reg (parmreg);
4771 /* If this was an item that we received a pointer to, set DECL_RTL
4775 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4777 set_mem_attributes (x, parm, 1);
4778 SET_DECL_RTL (parm, x);
4782 SET_DECL_RTL (parm, parmreg);
4783 maybe_set_unchanging (DECL_RTL (parm), parm);
4786 /* Copy the value into the register. */
4787 if (nominal_mode != passed_mode
4788 || promoted_nominal_mode != promoted_mode)
4791 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4792 mode, by the caller. We now have to convert it to
4793 NOMINAL_MODE, if different. However, PARMREG may be in
4794 a different mode than NOMINAL_MODE if it is being stored
4797 If ENTRY_PARM is a hard register, it might be in a register
4798 not valid for operating in its mode (e.g., an odd-numbered
4799 register for a DFmode). In that case, moves are the only
4800 thing valid, so we can't do a convert from there. This
4801 occurs when the calling sequence allow such misaligned
4804 In addition, the conversion may involve a call, which could
4805 clobber parameters which haven't been copied to pseudo
4806 registers yet. Therefore, we must first copy the parm to
4807 a pseudo reg here, and save the conversion until after all
4808 parameters have been moved. */
4810 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4812 emit_move_insn (tempreg, validize_mem (entry_parm));
4814 push_to_sequence (conversion_insns);
4815 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4817 if (GET_CODE (tempreg) == SUBREG
4818 && GET_MODE (tempreg) == nominal_mode
4819 && GET_CODE (SUBREG_REG (tempreg)) == REG
4820 && nominal_mode == passed_mode
4821 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4822 && GET_MODE_SIZE (GET_MODE (tempreg))
4823 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4825 /* The argument is already sign/zero extended, so note it
4827 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4828 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4831 /* TREE_USED gets set erroneously during expand_assignment. */
4832 save_tree_used = TREE_USED (parm);
4833 expand_assignment (parm,
4834 make_tree (nominal_type, tempreg), 0, 0);
4835 TREE_USED (parm) = save_tree_used;
4836 conversion_insns = get_insns ();
4841 emit_move_insn (parmreg, validize_mem (entry_parm));
4843 /* If we were passed a pointer but the actual value
4844 can safely live in a register, put it in one. */
4845 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4846 /* If by-reference argument was promoted, demote it. */
4847 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4849 && ! DECL_REGISTER (parm))
4850 || TREE_SIDE_EFFECTS (parm)
4851 /* If -ffloat-store specified, don't put explicit
4852 float variables into registers. */
4853 || (flag_float_store
4854 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4856 /* We can't use nominal_mode, because it will have been set to
4857 Pmode above. We must use the actual mode of the parm. */
4858 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4859 mark_user_reg (parmreg);
4860 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4862 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4863 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4864 push_to_sequence (conversion_insns);
4865 emit_move_insn (tempreg, DECL_RTL (parm));
4867 convert_to_mode (GET_MODE (parmreg),
4870 emit_move_insn (parmreg, DECL_RTL (parm));
4871 conversion_insns = get_insns();
4876 emit_move_insn (parmreg, DECL_RTL (parm));
4877 SET_DECL_RTL (parm, parmreg);
4878 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4882 #ifdef FUNCTION_ARG_CALLEE_COPIES
4883 /* If we are passed an arg by reference and it is our responsibility
4884 to make a copy, do it now.
4885 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4886 original argument, so we must recreate them in the call to
4887 FUNCTION_ARG_CALLEE_COPIES. */
4888 /* ??? Later add code to handle the case that if the argument isn't
4889 modified, don't do the copy. */
4891 else if (passed_pointer
4892 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4893 TYPE_MODE (DECL_ARG_TYPE (parm)),
4894 DECL_ARG_TYPE (parm),
4896 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4899 tree type = DECL_ARG_TYPE (parm);
4901 /* This sequence may involve a library call perhaps clobbering
4902 registers that haven't been copied to pseudos yet. */
4904 push_to_sequence (conversion_insns);
4906 if (!COMPLETE_TYPE_P (type)
4907 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4908 /* This is a variable sized object. */
4909 copy = gen_rtx_MEM (BLKmode,
4910 allocate_dynamic_stack_space
4911 (expr_size (parm), NULL_RTX,
4912 TYPE_ALIGN (type)));
4914 copy = assign_stack_temp (TYPE_MODE (type),
4915 int_size_in_bytes (type), 1);
4916 set_mem_attributes (copy, parm, 1);
4918 store_expr (parm, copy, 0);
4919 emit_move_insn (parmreg, XEXP (copy, 0));
4920 conversion_insns = get_insns ();
4924 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4926 /* In any case, record the parm's desired stack location
4927 in case we later discover it must live in the stack.
4929 If it is a COMPLEX value, store the stack location for both
4932 if (GET_CODE (parmreg) == CONCAT)
4933 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4935 regno = REGNO (parmreg);
4937 if (regno >= max_parm_reg)
4940 int old_max_parm_reg = max_parm_reg;
4942 /* It's slow to expand this one register at a time,
4943 but it's also rare and we need max_parm_reg to be
4944 precisely correct. */
4945 max_parm_reg = regno + 1;
4946 new = (rtx *) ggc_realloc (parm_reg_stack_loc,
4947 max_parm_reg * sizeof (rtx));
4948 memset ((char *) (new + old_max_parm_reg), 0,
4949 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4950 parm_reg_stack_loc = new;
4953 if (GET_CODE (parmreg) == CONCAT)
4955 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4957 regnor = REGNO (gen_realpart (submode, parmreg));
4958 regnoi = REGNO (gen_imagpart (submode, parmreg));
4960 if (stack_parm != 0)
4962 parm_reg_stack_loc[regnor]
4963 = gen_realpart (submode, stack_parm);
4964 parm_reg_stack_loc[regnoi]
4965 = gen_imagpart (submode, stack_parm);
4969 parm_reg_stack_loc[regnor] = 0;
4970 parm_reg_stack_loc[regnoi] = 0;
4974 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4976 /* Mark the register as eliminable if we did no conversion
4977 and it was copied from memory at a fixed offset,
4978 and the arg pointer was not copied to a pseudo-reg.
4979 If the arg pointer is a pseudo reg or the offset formed
4980 an invalid address, such memory-equivalences
4981 as we make here would screw up life analysis for it. */
4982 if (nominal_mode == passed_mode
4985 && GET_CODE (stack_parm) == MEM
4986 && stack_offset.var == 0
4987 && reg_mentioned_p (virtual_incoming_args_rtx,
4988 XEXP (stack_parm, 0)))
4990 rtx linsn = get_last_insn ();
4993 /* Mark complex types separately. */
4994 if (GET_CODE (parmreg) == CONCAT)
4995 /* Scan backwards for the set of the real and
4997 for (sinsn = linsn; sinsn != 0;
4998 sinsn = prev_nonnote_insn (sinsn))
5000 set = single_set (sinsn);
5002 && SET_DEST (set) == regno_reg_rtx [regnoi])
5004 = gen_rtx_EXPR_LIST (REG_EQUIV,
5005 parm_reg_stack_loc[regnoi],
5008 && SET_DEST (set) == regno_reg_rtx [regnor])
5010 = gen_rtx_EXPR_LIST (REG_EQUIV,
5011 parm_reg_stack_loc[regnor],
5014 else if ((set = single_set (linsn)) != 0
5015 && SET_DEST (set) == parmreg)
5017 = gen_rtx_EXPR_LIST (REG_EQUIV,
5018 stack_parm, REG_NOTES (linsn));
5021 /* For pointer data type, suggest pointer register. */
5022 if (POINTER_TYPE_P (TREE_TYPE (parm)))
5023 mark_reg_pointer (parmreg,
5024 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5026 /* If something wants our address, try to use ADDRESSOF. */
5027 if (TREE_ADDRESSABLE (parm))
5029 /* If we end up putting something into the stack,
5030 fixup_var_refs_insns will need to make a pass over
5031 all the instructions. It looks through the pending
5032 sequences -- but it can't see the ones in the
5033 CONVERSION_INSNS, if they're not on the sequence
5034 stack. So, we go back to that sequence, just so that
5035 the fixups will happen. */
5036 push_to_sequence (conversion_insns);
5037 put_var_into_stack (parm, /*rescan=*/true);
5038 conversion_insns = get_insns ();
5044 /* Value must be stored in the stack slot STACK_PARM
5045 during function execution. */
5047 if (promoted_mode != nominal_mode)
5049 /* Conversion is required. */
5050 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
5052 emit_move_insn (tempreg, validize_mem (entry_parm));
5054 push_to_sequence (conversion_insns);
5055 entry_parm = convert_to_mode (nominal_mode, tempreg,
5056 TREE_UNSIGNED (TREE_TYPE (parm)));
5058 /* ??? This may need a big-endian conversion on sparc64. */
5059 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
5061 conversion_insns = get_insns ();
5066 if (entry_parm != stack_parm)
5068 if (stack_parm == 0)
5071 = assign_stack_local (GET_MODE (entry_parm),
5072 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
5073 set_mem_attributes (stack_parm, parm, 1);
5076 if (promoted_mode != nominal_mode)
5078 push_to_sequence (conversion_insns);
5079 emit_move_insn (validize_mem (stack_parm),
5080 validize_mem (entry_parm));
5081 conversion_insns = get_insns ();
5085 emit_move_insn (validize_mem (stack_parm),
5086 validize_mem (entry_parm));
5089 SET_DECL_RTL (parm, stack_parm);
5093 /* Output all parameter conversion instructions (possibly including calls)
5094 now that all parameters have been copied out of hard registers. */
5095 emit_insn (conversion_insns);
5097 /* If we are receiving a struct value address as the first argument, set up
5098 the RTL for the function result. As this might require code to convert
5099 the transmitted address to Pmode, we do this here to ensure that possible
5100 preliminary conversions of the address have been emitted already. */
5101 if (function_result_decl)
5103 tree result = DECL_RESULT (fndecl);
5104 rtx addr = DECL_RTL (function_result_decl);
5107 #ifdef POINTERS_EXTEND_UNSIGNED
5108 if (GET_MODE (addr) != Pmode)
5109 addr = convert_memory_address (Pmode, addr);
5112 x = gen_rtx_MEM (DECL_MODE (result), addr);
5113 set_mem_attributes (x, result, 1);
5114 SET_DECL_RTL (result, x);
5117 last_parm_insn = get_last_insn ();
5119 current_function_args_size = stack_args_size.constant;
5121 /* Adjust function incoming argument size for alignment and
5124 #ifdef REG_PARM_STACK_SPACE
5125 #ifndef MAYBE_REG_PARM_STACK_SPACE
5126 current_function_args_size = MAX (current_function_args_size,
5127 REG_PARM_STACK_SPACE (fndecl));
5131 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
5133 current_function_args_size
5134 = ((current_function_args_size + STACK_BYTES - 1)
5135 / STACK_BYTES) * STACK_BYTES;
5137 #ifdef ARGS_GROW_DOWNWARD
5138 current_function_arg_offset_rtx
5139 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5140 : expand_expr (size_diffop (stack_args_size.var,
5141 size_int (-stack_args_size.constant)),
5142 NULL_RTX, VOIDmode, 0));
5144 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5147 /* See how many bytes, if any, of its args a function should try to pop
5150 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5151 current_function_args_size);
5153 /* For stdarg.h function, save info about
5154 regs and stack space used by the named args. */
5156 current_function_args_info = args_so_far;
5158 /* Set the rtx used for the function return value. Put this in its
5159 own variable so any optimizers that need this information don't have
5160 to include tree.h. Do this here so it gets done when an inlined
5161 function gets output. */
5163 current_function_return_rtx
5164 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5165 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5167 /* If scalar return value was computed in a pseudo-reg, or was a named
5168 return value that got dumped to the stack, copy that to the hard
5170 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5172 tree decl_result = DECL_RESULT (fndecl);
5173 rtx decl_rtl = DECL_RTL (decl_result);
5175 if (REG_P (decl_rtl)
5176 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5177 : DECL_REGISTER (decl_result))
5181 #ifdef FUNCTION_OUTGOING_VALUE
5182 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5185 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5188 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5189 /* The delay slot scheduler assumes that current_function_return_rtx
5190 holds the hard register containing the return value, not a
5191 temporary pseudo. */
5192 current_function_return_rtx = real_decl_rtl;
5197 /* Indicate whether REGNO is an incoming argument to the current function
5198 that was promoted to a wider mode. If so, return the RTX for the
5199 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5200 that REGNO is promoted from and whether the promotion was signed or
5203 #ifdef PROMOTE_FUNCTION_ARGS
5206 promoted_input_arg (regno, pmode, punsignedp)
5208 enum machine_mode *pmode;
5213 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5214 arg = TREE_CHAIN (arg))
5215 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5216 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5217 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5219 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5220 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5222 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5223 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5224 && mode != DECL_MODE (arg))
5226 *pmode = DECL_MODE (arg);
5227 *punsignedp = unsignedp;
5228 return DECL_INCOMING_RTL (arg);
5237 /* Compute the size and offset from the start of the stacked arguments for a
5238 parm passed in mode PASSED_MODE and with type TYPE.
5240 INITIAL_OFFSET_PTR points to the current offset into the stacked
5243 The starting offset and size for this parm are returned in *OFFSET_PTR
5244 and *ARG_SIZE_PTR, respectively.
5246 IN_REGS is nonzero if the argument will be passed in registers. It will
5247 never be set if REG_PARM_STACK_SPACE is not defined.
5249 FNDECL is the function in which the argument was defined.
5251 There are two types of rounding that are done. The first, controlled by
5252 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5253 list to be aligned to the specific boundary (in bits). This rounding
5254 affects the initial and starting offsets, but not the argument size.
5256 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5257 optionally rounds the size of the parm to PARM_BOUNDARY. The
5258 initial offset is not affected by this rounding, while the size always
5259 is and the starting offset may be. */
5261 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
5262 initial_offset_ptr is positive because locate_and_pad_parm's
5263 callers pass in the total size of args so far as
5264 initial_offset_ptr. arg_size_ptr is always positive. */
5267 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
5268 initial_offset_ptr, offset_ptr, arg_size_ptr,
5270 enum machine_mode passed_mode;
5272 int in_regs ATTRIBUTE_UNUSED;
5273 tree fndecl ATTRIBUTE_UNUSED;
5274 struct args_size *initial_offset_ptr;
5275 struct args_size *offset_ptr;
5276 struct args_size *arg_size_ptr;
5277 struct args_size *alignment_pad;
5281 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5282 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5283 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5284 #ifdef ARGS_GROW_DOWNWARD
5288 #ifdef REG_PARM_STACK_SPACE
5289 /* If we have found a stack parm before we reach the end of the
5290 area reserved for registers, skip that area. */
5293 int reg_parm_stack_space = 0;
5295 #ifdef MAYBE_REG_PARM_STACK_SPACE
5296 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5298 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5300 if (reg_parm_stack_space > 0)
5302 if (initial_offset_ptr->var)
5304 initial_offset_ptr->var
5305 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5306 ssize_int (reg_parm_stack_space));
5307 initial_offset_ptr->constant = 0;
5309 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5310 initial_offset_ptr->constant = reg_parm_stack_space;
5313 #endif /* REG_PARM_STACK_SPACE */
5315 arg_size_ptr->var = 0;
5316 arg_size_ptr->constant = 0;
5317 alignment_pad->var = 0;
5318 alignment_pad->constant = 0;
5320 #ifdef ARGS_GROW_DOWNWARD
5321 if (initial_offset_ptr->var)
5323 offset_ptr->constant = 0;
5324 offset_ptr->var = size_binop (MINUS_EXPR, ssize_int (0),
5325 initial_offset_ptr->var);
5329 offset_ptr->constant = -initial_offset_ptr->constant;
5330 offset_ptr->var = 0;
5333 if (where_pad != none
5334 && (!host_integerp (sizetree, 1)
5335 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5336 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
5337 SUB_PARM_SIZE (*offset_ptr, s2);
5340 #ifdef REG_PARM_STACK_SPACE
5341 || REG_PARM_STACK_SPACE (fndecl) > 0
5344 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5346 if (initial_offset_ptr->var)
5347 arg_size_ptr->var = size_binop (MINUS_EXPR,
5348 size_binop (MINUS_EXPR,
5350 initial_offset_ptr->var),
5354 arg_size_ptr->constant = (-initial_offset_ptr->constant
5355 - offset_ptr->constant);
5357 /* Pad_below needs the pre-rounded size to know how much to pad below.
5358 We only pad parameters which are not in registers as they have their
5359 padding done elsewhere. */
5360 if (where_pad == downward
5362 pad_below (offset_ptr, passed_mode, sizetree);
5364 #else /* !ARGS_GROW_DOWNWARD */
5366 #ifdef REG_PARM_STACK_SPACE
5367 || REG_PARM_STACK_SPACE (fndecl) > 0
5370 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5371 *offset_ptr = *initial_offset_ptr;
5373 #ifdef PUSH_ROUNDING
5374 if (passed_mode != BLKmode)
5375 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5378 /* Pad_below needs the pre-rounded size to know how much to pad below
5379 so this must be done before rounding up. */
5380 if (where_pad == downward
5381 /* However, BLKmode args passed in regs have their padding done elsewhere.
5382 The stack slot must be able to hold the entire register. */
5383 && !(in_regs && passed_mode == BLKmode))
5384 pad_below (offset_ptr, passed_mode, sizetree);
5386 if (where_pad != none
5387 && (!host_integerp (sizetree, 1)
5388 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5389 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5391 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5392 #endif /* ARGS_GROW_DOWNWARD */
5395 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5396 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5399 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5400 struct args_size *offset_ptr;
5402 struct args_size *alignment_pad;
5404 tree save_var = NULL_TREE;
5405 HOST_WIDE_INT save_constant = 0;
5407 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5409 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5411 save_var = offset_ptr->var;
5412 save_constant = offset_ptr->constant;
5415 alignment_pad->var = NULL_TREE;
5416 alignment_pad->constant = 0;
5418 if (boundary > BITS_PER_UNIT)
5420 if (offset_ptr->var)
5423 #ifdef ARGS_GROW_DOWNWARD
5428 (ARGS_SIZE_TREE (*offset_ptr),
5429 boundary / BITS_PER_UNIT);
5430 offset_ptr->constant = 0; /*?*/
5431 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5432 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5437 offset_ptr->constant =
5438 #ifdef ARGS_GROW_DOWNWARD
5439 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5441 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5443 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5444 alignment_pad->constant = offset_ptr->constant - save_constant;
5450 pad_below (offset_ptr, passed_mode, sizetree)
5451 struct args_size *offset_ptr;
5452 enum machine_mode passed_mode;
5455 if (passed_mode != BLKmode)
5457 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5458 offset_ptr->constant
5459 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5460 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5461 - GET_MODE_SIZE (passed_mode));
5465 if (TREE_CODE (sizetree) != INTEGER_CST
5466 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5468 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5469 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5471 ADD_PARM_SIZE (*offset_ptr, s2);
5472 SUB_PARM_SIZE (*offset_ptr, sizetree);
5477 /* Walk the tree of blocks describing the binding levels within a function
5478 and warn about uninitialized variables.
5479 This is done after calling flow_analysis and before global_alloc
5480 clobbers the pseudo-regs to hard regs. */
5483 uninitialized_vars_warning (block)
5487 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5489 if (warn_uninitialized
5490 && TREE_CODE (decl) == VAR_DECL
5491 /* These warnings are unreliable for and aggregates
5492 because assigning the fields one by one can fail to convince
5493 flow.c that the entire aggregate was initialized.
5494 Unions are troublesome because members may be shorter. */
5495 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5496 && DECL_RTL (decl) != 0
5497 && GET_CODE (DECL_RTL (decl)) == REG
5498 /* Global optimizations can make it difficult to determine if a
5499 particular variable has been initialized. However, a VAR_DECL
5500 with a nonzero DECL_INITIAL had an initializer, so do not
5501 claim it is potentially uninitialized.
5503 We do not care about the actual value in DECL_INITIAL, so we do
5504 not worry that it may be a dangling pointer. */
5505 && DECL_INITIAL (decl) == NULL_TREE
5506 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5507 warning_with_decl (decl,
5508 "`%s' might be used uninitialized in this function");
5510 && TREE_CODE (decl) == VAR_DECL
5511 && DECL_RTL (decl) != 0
5512 && GET_CODE (DECL_RTL (decl)) == REG
5513 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5514 warning_with_decl (decl,
5515 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5517 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5518 uninitialized_vars_warning (sub);
5521 /* Do the appropriate part of uninitialized_vars_warning
5522 but for arguments instead of local variables. */
5525 setjmp_args_warning ()
5528 for (decl = DECL_ARGUMENTS (current_function_decl);
5529 decl; decl = TREE_CHAIN (decl))
5530 if (DECL_RTL (decl) != 0
5531 && GET_CODE (DECL_RTL (decl)) == REG
5532 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5533 warning_with_decl (decl,
5534 "argument `%s' might be clobbered by `longjmp' or `vfork'");
5537 /* If this function call setjmp, put all vars into the stack
5538 unless they were declared `register'. */
5541 setjmp_protect (block)
5545 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5546 if ((TREE_CODE (decl) == VAR_DECL
5547 || TREE_CODE (decl) == PARM_DECL)
5548 && DECL_RTL (decl) != 0
5549 && (GET_CODE (DECL_RTL (decl)) == REG
5550 || (GET_CODE (DECL_RTL (decl)) == MEM
5551 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5552 /* If this variable came from an inline function, it must be
5553 that its life doesn't overlap the setjmp. If there was a
5554 setjmp in the function, it would already be in memory. We
5555 must exclude such variable because their DECL_RTL might be
5556 set to strange things such as virtual_stack_vars_rtx. */
5557 && ! DECL_FROM_INLINE (decl)
5559 #ifdef NON_SAVING_SETJMP
5560 /* If longjmp doesn't restore the registers,
5561 don't put anything in them. */
5565 ! DECL_REGISTER (decl)))
5566 put_var_into_stack (decl, /*rescan=*/true);
5567 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5568 setjmp_protect (sub);
5571 /* Like the previous function, but for args instead of local variables. */
5574 setjmp_protect_args ()
5577 for (decl = DECL_ARGUMENTS (current_function_decl);
5578 decl; decl = TREE_CHAIN (decl))
5579 if ((TREE_CODE (decl) == VAR_DECL
5580 || TREE_CODE (decl) == PARM_DECL)
5581 && DECL_RTL (decl) != 0
5582 && (GET_CODE (DECL_RTL (decl)) == REG
5583 || (GET_CODE (DECL_RTL (decl)) == MEM
5584 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5586 /* If longjmp doesn't restore the registers,
5587 don't put anything in them. */
5588 #ifdef NON_SAVING_SETJMP
5592 ! DECL_REGISTER (decl)))
5593 put_var_into_stack (decl, /*rescan=*/true);
5596 /* Return the context-pointer register corresponding to DECL,
5597 or 0 if it does not need one. */
5600 lookup_static_chain (decl)
5603 tree context = decl_function_context (decl);
5607 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5610 /* We treat inline_function_decl as an alias for the current function
5611 because that is the inline function whose vars, types, etc.
5612 are being merged into the current function.
5613 See expand_inline_function. */
5614 if (context == current_function_decl || context == inline_function_decl)
5615 return virtual_stack_vars_rtx;
5617 for (link = context_display; link; link = TREE_CHAIN (link))
5618 if (TREE_PURPOSE (link) == context)
5619 return RTL_EXPR_RTL (TREE_VALUE (link));
5624 /* Convert a stack slot address ADDR for variable VAR
5625 (from a containing function)
5626 into an address valid in this function (using a static chain). */
5629 fix_lexical_addr (addr, var)
5634 HOST_WIDE_INT displacement;
5635 tree context = decl_function_context (var);
5636 struct function *fp;
5639 /* If this is the present function, we need not do anything. */
5640 if (context == current_function_decl || context == inline_function_decl)
5643 fp = find_function_data (context);
5645 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5646 addr = XEXP (XEXP (addr, 0), 0);
5648 /* Decode given address as base reg plus displacement. */
5649 if (GET_CODE (addr) == REG)
5650 basereg = addr, displacement = 0;
5651 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5652 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5656 /* We accept vars reached via the containing function's
5657 incoming arg pointer and via its stack variables pointer. */
5658 if (basereg == fp->internal_arg_pointer)
5660 /* If reached via arg pointer, get the arg pointer value
5661 out of that function's stack frame.
5663 There are two cases: If a separate ap is needed, allocate a
5664 slot in the outer function for it and dereference it that way.
5665 This is correct even if the real ap is actually a pseudo.
5666 Otherwise, just adjust the offset from the frame pointer to
5669 #ifdef NEED_SEPARATE_AP
5672 addr = get_arg_pointer_save_area (fp);
5673 addr = fix_lexical_addr (XEXP (addr, 0), var);
5674 addr = memory_address (Pmode, addr);
5676 base = gen_rtx_MEM (Pmode, addr);
5677 set_mem_alias_set (base, get_frame_alias_set ());
5678 base = copy_to_reg (base);
5680 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5681 base = lookup_static_chain (var);
5685 else if (basereg == virtual_stack_vars_rtx)
5687 /* This is the same code as lookup_static_chain, duplicated here to
5688 avoid an extra call to decl_function_context. */
5691 for (link = context_display; link; link = TREE_CHAIN (link))
5692 if (TREE_PURPOSE (link) == context)
5694 base = RTL_EXPR_RTL (TREE_VALUE (link));
5702 /* Use same offset, relative to appropriate static chain or argument
5704 return plus_constant (base, displacement);
5707 /* Return the address of the trampoline for entering nested fn FUNCTION.
5708 If necessary, allocate a trampoline (in the stack frame)
5709 and emit rtl to initialize its contents (at entry to this function). */
5712 trampoline_address (function)
5718 struct function *fp;
5721 /* Find an existing trampoline and return it. */
5722 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5723 if (TREE_PURPOSE (link) == function)
5725 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5727 for (fp = outer_function_chain; fp; fp = fp->outer)
5728 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5729 if (TREE_PURPOSE (link) == function)
5731 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5733 return adjust_trampoline_addr (tramp);
5736 /* None exists; we must make one. */
5738 /* Find the `struct function' for the function containing FUNCTION. */
5740 fn_context = decl_function_context (function);
5741 if (fn_context != current_function_decl
5742 && fn_context != inline_function_decl)
5743 fp = find_function_data (fn_context);
5745 /* Allocate run-time space for this trampoline
5746 (usually in the defining function's stack frame). */
5747 #ifdef ALLOCATE_TRAMPOLINE
5748 tramp = ALLOCATE_TRAMPOLINE (fp);
5750 /* If rounding needed, allocate extra space
5751 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5752 #define TRAMPOLINE_REAL_SIZE \
5753 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5754 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5758 /* Record the trampoline for reuse and note it for later initialization
5759 by expand_function_end. */
5762 rtlexp = make_node (RTL_EXPR);
5763 RTL_EXPR_RTL (rtlexp) = tramp;
5764 fp->x_trampoline_list = tree_cons (function, rtlexp,
5765 fp->x_trampoline_list);
5769 /* Make the RTL_EXPR node temporary, not momentary, so that the
5770 trampoline_list doesn't become garbage. */
5771 rtlexp = make_node (RTL_EXPR);
5773 RTL_EXPR_RTL (rtlexp) = tramp;
5774 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5777 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5778 return adjust_trampoline_addr (tramp);
5781 /* Given a trampoline address,
5782 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5785 round_trampoline_addr (tramp)
5788 /* Round address up to desired boundary. */
5789 rtx temp = gen_reg_rtx (Pmode);
5790 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
5791 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5793 temp = expand_simple_binop (Pmode, PLUS, tramp, addend,
5794 temp, 0, OPTAB_LIB_WIDEN);
5795 tramp = expand_simple_binop (Pmode, AND, temp, mask,
5796 temp, 0, OPTAB_LIB_WIDEN);
5801 /* Given a trampoline address, round it then apply any
5802 platform-specific adjustments so that the result can be used for a
5806 adjust_trampoline_addr (tramp)
5809 tramp = round_trampoline_addr (tramp);
5810 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5811 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5816 /* Put all this function's BLOCK nodes including those that are chained
5817 onto the first block into a vector, and return it.
5818 Also store in each NOTE for the beginning or end of a block
5819 the index of that block in the vector.
5820 The arguments are BLOCK, the chain of top-level blocks of the function,
5821 and INSNS, the insn chain of the function. */
5827 tree *block_vector, *last_block_vector;
5829 tree block = DECL_INITIAL (current_function_decl);
5834 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5835 depth-first order. */
5836 block_vector = get_block_vector (block, &n_blocks);
5837 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5839 last_block_vector = identify_blocks_1 (get_insns (),
5841 block_vector + n_blocks,
5844 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5845 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5846 if (0 && last_block_vector != block_vector + n_blocks)
5849 free (block_vector);
5853 /* Subroutine of identify_blocks. Do the block substitution on the
5854 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5856 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5857 BLOCK_VECTOR is incremented for each block seen. */
5860 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5863 tree *end_block_vector;
5864 tree *orig_block_stack;
5867 tree *block_stack = orig_block_stack;
5869 for (insn = insns; insn; insn = NEXT_INSN (insn))
5871 if (GET_CODE (insn) == NOTE)
5873 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5877 /* If there are more block notes than BLOCKs, something
5879 if (block_vector == end_block_vector)
5882 b = *block_vector++;
5883 NOTE_BLOCK (insn) = b;
5886 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5888 /* If there are more NOTE_INSN_BLOCK_ENDs than
5889 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5890 if (block_stack == orig_block_stack)
5893 NOTE_BLOCK (insn) = *--block_stack;
5896 else if (GET_CODE (insn) == CALL_INSN
5897 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5899 rtx cp = PATTERN (insn);
5901 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5902 end_block_vector, block_stack);
5904 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5905 end_block_vector, block_stack);
5907 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5908 end_block_vector, block_stack);
5912 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5913 something is badly wrong. */
5914 if (block_stack != orig_block_stack)
5917 return block_vector;
5920 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5921 and create duplicate blocks. */
5922 /* ??? Need an option to either create block fragments or to create
5923 abstract origin duplicates of a source block. It really depends
5924 on what optimization has been performed. */
5929 tree block = DECL_INITIAL (current_function_decl);
5930 varray_type block_stack;
5932 if (block == NULL_TREE)
5935 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5937 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
5938 reorder_blocks_0 (block);
5940 /* Prune the old trees away, so that they don't get in the way. */
5941 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5942 BLOCK_CHAIN (block) = NULL_TREE;
5944 /* Recreate the block tree from the note nesting. */
5945 reorder_blocks_1 (get_insns (), block, &block_stack);
5946 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5948 /* Remove deleted blocks from the block fragment chains. */
5949 reorder_fix_fragments (block);
5952 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
5955 reorder_blocks_0 (block)
5960 TREE_ASM_WRITTEN (block) = 0;
5961 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
5962 block = BLOCK_CHAIN (block);
5967 reorder_blocks_1 (insns, current_block, p_block_stack)
5970 varray_type *p_block_stack;
5974 for (insn = insns; insn; insn = NEXT_INSN (insn))
5976 if (GET_CODE (insn) == NOTE)
5978 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5980 tree block = NOTE_BLOCK (insn);
5982 /* If we have seen this block before, that means it now
5983 spans multiple address regions. Create a new fragment. */
5984 if (TREE_ASM_WRITTEN (block))
5986 tree new_block = copy_node (block);
5989 origin = (BLOCK_FRAGMENT_ORIGIN (block)
5990 ? BLOCK_FRAGMENT_ORIGIN (block)
5992 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
5993 BLOCK_FRAGMENT_CHAIN (new_block)
5994 = BLOCK_FRAGMENT_CHAIN (origin);
5995 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
5997 NOTE_BLOCK (insn) = new_block;
6001 BLOCK_SUBBLOCKS (block) = 0;
6002 TREE_ASM_WRITTEN (block) = 1;
6003 /* When there's only one block for the entire function,
6004 current_block == block and we mustn't do this, it
6005 will cause infinite recursion. */
6006 if (block != current_block)
6008 BLOCK_SUPERCONTEXT (block) = current_block;
6009 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
6010 BLOCK_SUBBLOCKS (current_block) = block;
6011 current_block = block;
6013 VARRAY_PUSH_TREE (*p_block_stack, block);
6015 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
6017 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
6018 VARRAY_POP (*p_block_stack);
6019 BLOCK_SUBBLOCKS (current_block)
6020 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
6021 current_block = BLOCK_SUPERCONTEXT (current_block);
6024 else if (GET_CODE (insn) == CALL_INSN
6025 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
6027 rtx cp = PATTERN (insn);
6028 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
6030 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
6032 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
6037 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
6038 appears in the block tree, select one of the fragments to become
6039 the new origin block. */
6042 reorder_fix_fragments (block)
6047 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
6048 tree new_origin = NULL_TREE;
6052 if (! TREE_ASM_WRITTEN (dup_origin))
6054 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
6056 /* Find the first of the remaining fragments. There must
6057 be at least one -- the current block. */
6058 while (! TREE_ASM_WRITTEN (new_origin))
6059 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
6060 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
6063 else if (! dup_origin)
6066 /* Re-root the rest of the fragments to the new origin. In the
6067 case that DUP_ORIGIN was null, that means BLOCK was the origin
6068 of a chain of fragments and we want to remove those fragments
6069 that didn't make it to the output. */
6072 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
6077 if (TREE_ASM_WRITTEN (chain))
6079 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
6081 pp = &BLOCK_FRAGMENT_CHAIN (chain);
6083 chain = BLOCK_FRAGMENT_CHAIN (chain);
6088 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
6089 block = BLOCK_CHAIN (block);
6093 /* Reverse the order of elements in the chain T of blocks,
6094 and return the new head of the chain (old last element). */
6100 tree prev = 0, decl, next;
6101 for (decl = t; decl; decl = next)
6103 next = BLOCK_CHAIN (decl);
6104 BLOCK_CHAIN (decl) = prev;
6110 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6111 non-NULL, list them all into VECTOR, in a depth-first preorder
6112 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6116 all_blocks (block, vector)
6124 TREE_ASM_WRITTEN (block) = 0;
6126 /* Record this block. */
6128 vector[n_blocks] = block;
6132 /* Record the subblocks, and their subblocks... */
6133 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6134 vector ? vector + n_blocks : 0);
6135 block = BLOCK_CHAIN (block);
6141 /* Return a vector containing all the blocks rooted at BLOCK. The
6142 number of elements in the vector is stored in N_BLOCKS_P. The
6143 vector is dynamically allocated; it is the caller's responsibility
6144 to call `free' on the pointer returned. */
6147 get_block_vector (block, n_blocks_p)
6153 *n_blocks_p = all_blocks (block, NULL);
6154 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
6155 all_blocks (block, block_vector);
6157 return block_vector;
6160 static GTY(()) int next_block_index = 2;
6162 /* Set BLOCK_NUMBER for all the blocks in FN. */
6172 /* For SDB and XCOFF debugging output, we start numbering the blocks
6173 from 1 within each function, rather than keeping a running
6175 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6176 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6177 next_block_index = 1;
6180 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6182 /* The top-level BLOCK isn't numbered at all. */
6183 for (i = 1; i < n_blocks; ++i)
6184 /* We number the blocks from two. */
6185 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6187 free (block_vector);
6192 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6195 debug_find_var_in_block_tree (var, block)
6201 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6205 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6207 tree ret = debug_find_var_in_block_tree (var, t);
6215 /* Allocate a function structure and reset its contents to the defaults. */
6218 prepare_function_start ()
6220 cfun = (struct function *) ggc_alloc_cleared (sizeof (struct function));
6222 init_stmt_for_function ();
6223 init_eh_for_function ();
6225 cse_not_expected = ! optimize;
6227 /* Caller save not needed yet. */
6228 caller_save_needed = 0;
6230 /* No stack slots have been made yet. */
6231 stack_slot_list = 0;
6233 current_function_has_nonlocal_label = 0;
6234 current_function_has_nonlocal_goto = 0;
6236 /* There is no stack slot for handling nonlocal gotos. */
6237 nonlocal_goto_handler_slots = 0;
6238 nonlocal_goto_stack_level = 0;
6240 /* No labels have been declared for nonlocal use. */
6241 nonlocal_labels = 0;
6242 nonlocal_goto_handler_labels = 0;
6244 /* No function calls so far in this function. */
6245 function_call_count = 0;
6247 /* No parm regs have been allocated.
6248 (This is important for output_inline_function.) */
6249 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6251 /* Initialize the RTL mechanism. */
6254 /* Initialize the queue of pending postincrement and postdecrements,
6255 and some other info in expr.c. */
6258 /* We haven't done register allocation yet. */
6261 init_varasm_status (cfun);
6263 /* Clear out data used for inlining. */
6264 cfun->inlinable = 0;
6265 cfun->original_decl_initial = 0;
6266 cfun->original_arg_vector = 0;
6268 cfun->stack_alignment_needed = STACK_BOUNDARY;
6269 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6271 /* Set if a call to setjmp is seen. */
6272 current_function_calls_setjmp = 0;
6274 /* Set if a call to longjmp is seen. */
6275 current_function_calls_longjmp = 0;
6277 current_function_calls_alloca = 0;
6278 current_function_calls_eh_return = 0;
6279 current_function_calls_constant_p = 0;
6280 current_function_contains_functions = 0;
6281 current_function_is_leaf = 0;
6282 current_function_nothrow = 0;
6283 current_function_sp_is_unchanging = 0;
6284 current_function_uses_only_leaf_regs = 0;
6285 current_function_has_computed_jump = 0;
6286 current_function_is_thunk = 0;
6288 current_function_returns_pcc_struct = 0;
6289 current_function_returns_struct = 0;
6290 current_function_epilogue_delay_list = 0;
6291 current_function_uses_const_pool = 0;
6292 current_function_uses_pic_offset_table = 0;
6293 current_function_cannot_inline = 0;
6295 /* We have not yet needed to make a label to jump to for tail-recursion. */
6296 tail_recursion_label = 0;
6298 /* We haven't had a need to make a save area for ap yet. */
6299 arg_pointer_save_area = 0;
6301 /* No stack slots allocated yet. */
6304 /* No SAVE_EXPRs in this function yet. */
6307 /* No RTL_EXPRs in this function yet. */
6310 /* Set up to allocate temporaries. */
6313 /* Indicate that we need to distinguish between the return value of the
6314 present function and the return value of a function being called. */
6315 rtx_equal_function_value_matters = 1;
6317 /* Indicate that we have not instantiated virtual registers yet. */
6318 virtuals_instantiated = 0;
6320 /* Indicate that we want CONCATs now. */
6321 generating_concat_p = 1;
6323 /* Indicate we have no need of a frame pointer yet. */
6324 frame_pointer_needed = 0;
6326 /* By default assume not stdarg. */
6327 current_function_stdarg = 0;
6329 /* We haven't made any trampolines for this function yet. */
6330 trampoline_list = 0;
6332 init_pending_stack_adjust ();
6333 inhibit_defer_pop = 0;
6335 current_function_outgoing_args_size = 0;
6337 current_function_funcdef_no = funcdef_no++;
6339 cfun->arc_profile = profile_arc_flag || flag_test_coverage;
6341 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
6343 cfun->max_jumptable_ents = 0;
6345 (*lang_hooks.function.init) (cfun);
6346 if (init_machine_status)
6347 cfun->machine = (*init_machine_status) ();
6350 /* Initialize the rtl expansion mechanism so that we can do simple things
6351 like generate sequences. This is used to provide a context during global
6352 initialization of some passes. */
6354 init_dummy_function_start ()
6356 prepare_function_start ();
6359 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6360 and initialize static variables for generating RTL for the statements
6364 init_function_start (subr, filename, line)
6366 const char *filename;
6369 prepare_function_start ();
6371 current_function_name = (*lang_hooks.decl_printable_name) (subr, 2);
6374 /* Nonzero if this is a nested function that uses a static chain. */
6376 current_function_needs_context
6377 = (decl_function_context (current_function_decl) != 0
6378 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6380 /* Within function body, compute a type's size as soon it is laid out. */
6381 immediate_size_expand++;
6383 /* Prevent ever trying to delete the first instruction of a function.
6384 Also tell final how to output a linenum before the function prologue.
6385 Note linenums could be missing, e.g. when compiling a Java .class file. */
6387 emit_line_note (filename, line);
6389 /* Make sure first insn is a note even if we don't want linenums.
6390 This makes sure the first insn will never be deleted.
6391 Also, final expects a note to appear there. */
6392 emit_note (NULL, NOTE_INSN_DELETED);
6394 /* Set flags used by final.c. */
6395 if (aggregate_value_p (DECL_RESULT (subr)))
6397 #ifdef PCC_STATIC_STRUCT_RETURN
6398 current_function_returns_pcc_struct = 1;
6400 current_function_returns_struct = 1;
6403 /* Warn if this value is an aggregate type,
6404 regardless of which calling convention we are using for it. */
6405 if (warn_aggregate_return
6406 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6407 warning ("function returns an aggregate");
6409 current_function_returns_pointer
6410 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
6413 /* Make sure all values used by the optimization passes have sane
6416 init_function_for_compilation ()
6420 /* No prologue/epilogue insns yet. */
6421 VARRAY_GROW (prologue, 0);
6422 VARRAY_GROW (epilogue, 0);
6423 VARRAY_GROW (sibcall_epilogue, 0);
6426 /* Expand a call to __main at the beginning of a possible main function. */
6428 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6429 #undef HAS_INIT_SECTION
6430 #define HAS_INIT_SECTION
6434 expand_main_function ()
6436 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6437 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6439 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6443 /* Forcibly align the stack. */
6444 #ifdef STACK_GROWS_DOWNWARD
6445 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6446 stack_pointer_rtx, 1, OPTAB_WIDEN);
6448 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6449 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6450 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6451 stack_pointer_rtx, 1, OPTAB_WIDEN);
6453 if (tmp != stack_pointer_rtx)
6454 emit_move_insn (stack_pointer_rtx, tmp);
6456 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6457 tmp = force_reg (Pmode, const0_rtx);
6458 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6462 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6463 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6466 emit_insn_before (seq, tmp);
6472 #ifndef HAS_INIT_SECTION
6473 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), LCT_NORMAL,
6478 /* The PENDING_SIZES represent the sizes of variable-sized types.
6479 Create RTL for the various sizes now (using temporary variables),
6480 so that we can refer to the sizes from the RTL we are generating
6481 for the current function. The PENDING_SIZES are a TREE_LIST. The
6482 TREE_VALUE of each node is a SAVE_EXPR. */
6485 expand_pending_sizes (pending_sizes)
6490 /* Evaluate now the sizes of any types declared among the arguments. */
6491 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6493 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6494 /* Flush the queue in case this parameter declaration has
6500 /* Start the RTL for a new function, and set variables used for
6502 SUBR is the FUNCTION_DECL node.
6503 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6504 the function's parameters, which must be run at any return statement. */
6507 expand_function_start (subr, parms_have_cleanups)
6509 int parms_have_cleanups;
6512 rtx last_ptr = NULL_RTX;
6514 /* Make sure volatile mem refs aren't considered
6515 valid operands of arithmetic insns. */
6516 init_recog_no_volatile ();
6518 current_function_instrument_entry_exit
6519 = (flag_instrument_function_entry_exit
6520 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6522 current_function_profile
6524 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6526 current_function_limit_stack
6527 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6529 /* If function gets a static chain arg, store it in the stack frame.
6530 Do this first, so it gets the first stack slot offset. */
6531 if (current_function_needs_context)
6533 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6535 /* Delay copying static chain if it is not a register to avoid
6536 conflicts with regs used for parameters. */
6537 if (! SMALL_REGISTER_CLASSES
6538 || GET_CODE (static_chain_incoming_rtx) == REG)
6539 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6542 /* If the parameters of this function need cleaning up, get a label
6543 for the beginning of the code which executes those cleanups. This must
6544 be done before doing anything with return_label. */
6545 if (parms_have_cleanups)
6546 cleanup_label = gen_label_rtx ();
6550 /* Make the label for return statements to jump to. Do not special
6551 case machines with special return instructions -- they will be
6552 handled later during jump, ifcvt, or epilogue creation. */
6553 return_label = gen_label_rtx ();
6555 /* Initialize rtx used to return the value. */
6556 /* Do this before assign_parms so that we copy the struct value address
6557 before any library calls that assign parms might generate. */
6559 /* Decide whether to return the value in memory or in a register. */
6560 if (aggregate_value_p (DECL_RESULT (subr)))
6562 /* Returning something that won't go in a register. */
6563 rtx value_address = 0;
6565 #ifdef PCC_STATIC_STRUCT_RETURN
6566 if (current_function_returns_pcc_struct)
6568 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6569 value_address = assemble_static_space (size);
6574 /* Expect to be passed the address of a place to store the value.
6575 If it is passed as an argument, assign_parms will take care of
6577 if (struct_value_incoming_rtx)
6579 value_address = gen_reg_rtx (Pmode);
6580 emit_move_insn (value_address, struct_value_incoming_rtx);
6585 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6586 set_mem_attributes (x, DECL_RESULT (subr), 1);
6587 SET_DECL_RTL (DECL_RESULT (subr), x);
6590 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6591 /* If return mode is void, this decl rtl should not be used. */
6592 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6595 /* Compute the return values into a pseudo reg, which we will copy
6596 into the true return register after the cleanups are done. */
6598 /* In order to figure out what mode to use for the pseudo, we
6599 figure out what the mode of the eventual return register will
6600 actually be, and use that. */
6602 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6605 /* Structures that are returned in registers are not aggregate_value_p,
6606 so we may see a PARALLEL or a REG. */
6607 if (REG_P (hard_reg))
6608 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6609 else if (GET_CODE (hard_reg) == PARALLEL)
6610 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
6614 /* Set DECL_REGISTER flag so that expand_function_end will copy the
6615 result to the real return register(s). */
6616 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6619 /* Initialize rtx for parameters and local variables.
6620 In some cases this requires emitting insns. */
6622 assign_parms (subr);
6624 /* Copy the static chain now if it wasn't a register. The delay is to
6625 avoid conflicts with the parameter passing registers. */
6627 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6628 if (GET_CODE (static_chain_incoming_rtx) != REG)
6629 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6631 /* The following was moved from init_function_start.
6632 The move is supposed to make sdb output more accurate. */
6633 /* Indicate the beginning of the function body,
6634 as opposed to parm setup. */
6635 emit_note (NULL, NOTE_INSN_FUNCTION_BEG);
6637 if (GET_CODE (get_last_insn ()) != NOTE)
6638 emit_note (NULL, NOTE_INSN_DELETED);
6639 parm_birth_insn = get_last_insn ();
6641 context_display = 0;
6642 if (current_function_needs_context)
6644 /* Fetch static chain values for containing functions. */
6645 tem = decl_function_context (current_function_decl);
6646 /* Copy the static chain pointer into a pseudo. If we have
6647 small register classes, copy the value from memory if
6648 static_chain_incoming_rtx is a REG. */
6651 /* If the static chain originally came in a register, put it back
6652 there, then move it out in the next insn. The reason for
6653 this peculiar code is to satisfy function integration. */
6654 if (SMALL_REGISTER_CLASSES
6655 && GET_CODE (static_chain_incoming_rtx) == REG)
6656 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6657 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6662 tree rtlexp = make_node (RTL_EXPR);
6664 RTL_EXPR_RTL (rtlexp) = last_ptr;
6665 context_display = tree_cons (tem, rtlexp, context_display);
6666 tem = decl_function_context (tem);
6669 /* Chain thru stack frames, assuming pointer to next lexical frame
6670 is found at the place we always store it. */
6671 #ifdef FRAME_GROWS_DOWNWARD
6672 last_ptr = plus_constant (last_ptr,
6673 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6675 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6676 set_mem_alias_set (last_ptr, get_frame_alias_set ());
6677 last_ptr = copy_to_reg (last_ptr);
6679 /* If we are not optimizing, ensure that we know that this
6680 piece of context is live over the entire function. */
6682 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6687 if (current_function_instrument_entry_exit)
6689 rtx fun = DECL_RTL (current_function_decl);
6690 if (GET_CODE (fun) == MEM)
6691 fun = XEXP (fun, 0);
6694 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode,
6696 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6698 hard_frame_pointer_rtx),
6702 if (current_function_profile)
6705 PROFILE_HOOK (current_function_funcdef_no);
6709 /* After the display initializations is where the tail-recursion label
6710 should go, if we end up needing one. Ensure we have a NOTE here
6711 since some things (like trampolines) get placed before this. */
6712 tail_recursion_reentry = emit_note (NULL, NOTE_INSN_DELETED);
6714 /* Evaluate now the sizes of any types declared among the arguments. */
6715 expand_pending_sizes (nreverse (get_pending_sizes ()));
6717 /* Make sure there is a line number after the function entry setup code. */
6718 force_next_line_note ();
6721 /* Undo the effects of init_dummy_function_start. */
6723 expand_dummy_function_end ()
6725 /* End any sequences that failed to be closed due to syntax errors. */
6726 while (in_sequence_p ())
6729 /* Outside function body, can't compute type's actual size
6730 until next function's body starts. */
6732 free_after_parsing (cfun);
6733 free_after_compilation (cfun);
6737 /* Call DOIT for each hard register used as a return value from
6738 the current function. */
6741 diddle_return_value (doit, arg)
6742 void (*doit) PARAMS ((rtx, void *));
6745 rtx outgoing = current_function_return_rtx;
6750 if (GET_CODE (outgoing) == REG)
6751 (*doit) (outgoing, arg);
6752 else if (GET_CODE (outgoing) == PARALLEL)
6756 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6758 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6760 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6767 do_clobber_return_reg (reg, arg)
6769 void *arg ATTRIBUTE_UNUSED;
6771 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6775 clobber_return_register ()
6777 diddle_return_value (do_clobber_return_reg, NULL);
6779 /* In case we do use pseudo to return value, clobber it too. */
6780 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6782 tree decl_result = DECL_RESULT (current_function_decl);
6783 rtx decl_rtl = DECL_RTL (decl_result);
6784 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6786 do_clobber_return_reg (decl_rtl, NULL);
6792 do_use_return_reg (reg, arg)
6794 void *arg ATTRIBUTE_UNUSED;
6796 emit_insn (gen_rtx_USE (VOIDmode, reg));
6800 use_return_register ()
6802 diddle_return_value (do_use_return_reg, NULL);
6805 static GTY(()) rtx initial_trampoline;
6807 /* Generate RTL for the end of the current function.
6808 FILENAME and LINE are the current position in the source file.
6810 It is up to language-specific callers to do cleanups for parameters--
6811 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6814 expand_function_end (filename, line, end_bindings)
6815 const char *filename;
6822 finish_expr_for_function ();
6824 /* If arg_pointer_save_area was referenced only from a nested
6825 function, we will not have initialized it yet. Do that now. */
6826 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6827 get_arg_pointer_save_area (cfun);
6829 #ifdef NON_SAVING_SETJMP
6830 /* Don't put any variables in registers if we call setjmp
6831 on a machine that fails to restore the registers. */
6832 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6834 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6835 setjmp_protect (DECL_INITIAL (current_function_decl));
6837 setjmp_protect_args ();
6841 /* Initialize any trampolines required by this function. */
6842 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6844 tree function = TREE_PURPOSE (link);
6845 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6846 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6847 #ifdef TRAMPOLINE_TEMPLATE
6852 #ifdef TRAMPOLINE_TEMPLATE
6853 /* First make sure this compilation has a template for
6854 initializing trampolines. */
6855 if (initial_trampoline == 0)
6858 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6859 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
6863 /* Generate insns to initialize the trampoline. */
6865 tramp = round_trampoline_addr (XEXP (tramp, 0));
6866 #ifdef TRAMPOLINE_TEMPLATE
6867 blktramp = replace_equiv_address (initial_trampoline, tramp);
6868 emit_block_move (blktramp, initial_trampoline,
6869 GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL);
6871 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6875 /* Put those insns at entry to the containing function (this one). */
6876 emit_insn_before (seq, tail_recursion_reentry);
6879 /* If we are doing stack checking and this function makes calls,
6880 do a stack probe at the start of the function to ensure we have enough
6881 space for another stack frame. */
6882 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6886 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6887 if (GET_CODE (insn) == CALL_INSN)
6890 probe_stack_range (STACK_CHECK_PROTECT,
6891 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6894 emit_insn_before (seq, tail_recursion_reentry);
6899 /* Warn about unused parms if extra warnings were specified. */
6900 /* Either ``-Wextra -Wunused'' or ``-Wunused-parameter'' enables this
6901 warning. WARN_UNUSED_PARAMETER is negative when set by
6902 -Wunused. Note that -Wall implies -Wunused, so ``-Wall -Wextra'' will
6903 also give these warnings. */
6904 if (warn_unused_parameter > 0
6905 || (warn_unused_parameter < 0 && extra_warnings))
6909 for (decl = DECL_ARGUMENTS (current_function_decl);
6910 decl; decl = TREE_CHAIN (decl))
6911 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6912 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6913 warning_with_decl (decl, "unused parameter `%s'");
6916 /* Delete handlers for nonlocal gotos if nothing uses them. */
6917 if (nonlocal_goto_handler_slots != 0
6918 && ! current_function_has_nonlocal_label)
6921 /* End any sequences that failed to be closed due to syntax errors. */
6922 while (in_sequence_p ())
6925 /* Outside function body, can't compute type's actual size
6926 until next function's body starts. */
6927 immediate_size_expand--;
6929 clear_pending_stack_adjust ();
6930 do_pending_stack_adjust ();
6932 /* Mark the end of the function body.
6933 If control reaches this insn, the function can drop through
6934 without returning a value. */
6935 emit_note (NULL, NOTE_INSN_FUNCTION_END);
6937 /* Must mark the last line number note in the function, so that the test
6938 coverage code can avoid counting the last line twice. This just tells
6939 the code to ignore the immediately following line note, since there
6940 already exists a copy of this note somewhere above. This line number
6941 note is still needed for debugging though, so we can't delete it. */
6942 if (flag_test_coverage)
6943 emit_note (NULL, NOTE_INSN_REPEATED_LINE_NUMBER);
6945 /* Output a linenumber for the end of the function.
6946 SDB depends on this. */
6947 emit_line_note_force (filename, line);
6949 /* Before the return label (if any), clobber the return
6950 registers so that they are not propagated live to the rest of
6951 the function. This can only happen with functions that drop
6952 through; if there had been a return statement, there would
6953 have either been a return rtx, or a jump to the return label.
6955 We delay actual code generation after the current_function_value_rtx
6957 clobber_after = get_last_insn ();
6959 /* Output the label for the actual return from the function,
6960 if one is expected. This happens either because a function epilogue
6961 is used instead of a return instruction, or because a return was done
6962 with a goto in order to run local cleanups, or because of pcc-style
6963 structure returning. */
6965 emit_label (return_label);
6967 /* C++ uses this. */
6969 expand_end_bindings (0, 0, 0);
6971 if (current_function_instrument_entry_exit)
6973 rtx fun = DECL_RTL (current_function_decl);
6974 if (GET_CODE (fun) == MEM)
6975 fun = XEXP (fun, 0);
6978 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode,
6980 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6982 hard_frame_pointer_rtx),
6986 /* Let except.c know where it should emit the call to unregister
6987 the function context for sjlj exceptions. */
6988 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
6989 sjlj_emit_function_exit_after (get_last_insn ());
6991 /* If we had calls to alloca, and this machine needs
6992 an accurate stack pointer to exit the function,
6993 insert some code to save and restore the stack pointer. */
6994 #ifdef EXIT_IGNORE_STACK
6995 if (! EXIT_IGNORE_STACK)
6997 if (current_function_calls_alloca)
7001 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
7002 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
7005 /* If scalar return value was computed in a pseudo-reg, or was a named
7006 return value that got dumped to the stack, copy that to the hard
7008 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
7010 tree decl_result = DECL_RESULT (current_function_decl);
7011 rtx decl_rtl = DECL_RTL (decl_result);
7013 if (REG_P (decl_rtl)
7014 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
7015 : DECL_REGISTER (decl_result))
7017 rtx real_decl_rtl = current_function_return_rtx;
7019 /* This should be set in assign_parms. */
7020 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
7023 /* If this is a BLKmode structure being returned in registers,
7024 then use the mode computed in expand_return. Note that if
7025 decl_rtl is memory, then its mode may have been changed,
7026 but that current_function_return_rtx has not. */
7027 if (GET_MODE (real_decl_rtl) == BLKmode)
7028 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
7030 /* If a named return value dumped decl_return to memory, then
7031 we may need to re-do the PROMOTE_MODE signed/unsigned
7033 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
7035 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
7037 #ifdef PROMOTE_FUNCTION_RETURN
7038 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
7042 convert_move (real_decl_rtl, decl_rtl, unsignedp);
7044 else if (GET_CODE (real_decl_rtl) == PARALLEL)
7046 /* If expand_function_start has created a PARALLEL for decl_rtl,
7047 move the result to the real return registers. Otherwise, do
7048 a group load from decl_rtl for a named return. */
7049 if (GET_CODE (decl_rtl) == PARALLEL)
7050 emit_group_move (real_decl_rtl, decl_rtl);
7052 emit_group_load (real_decl_rtl, decl_rtl,
7053 int_size_in_bytes (TREE_TYPE (decl_result)));
7056 emit_move_insn (real_decl_rtl, decl_rtl);
7060 /* If returning a structure, arrange to return the address of the value
7061 in a place where debuggers expect to find it.
7063 If returning a structure PCC style,
7064 the caller also depends on this value.
7065 And current_function_returns_pcc_struct is not necessarily set. */
7066 if (current_function_returns_struct
7067 || current_function_returns_pcc_struct)
7070 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
7071 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
7072 #ifdef FUNCTION_OUTGOING_VALUE
7074 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
7075 current_function_decl);
7078 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
7081 /* Mark this as a function return value so integrate will delete the
7082 assignment and USE below when inlining this function. */
7083 REG_FUNCTION_VALUE_P (outgoing) = 1;
7085 #ifdef POINTERS_EXTEND_UNSIGNED
7086 /* The address may be ptr_mode and OUTGOING may be Pmode. */
7087 if (GET_MODE (outgoing) != GET_MODE (value_address))
7088 value_address = convert_memory_address (GET_MODE (outgoing),
7092 emit_move_insn (outgoing, value_address);
7094 /* Show return register used to hold result (in this case the address
7096 current_function_return_rtx = outgoing;
7099 /* If this is an implementation of throw, do what's necessary to
7100 communicate between __builtin_eh_return and the epilogue. */
7101 expand_eh_return ();
7103 /* Emit the actual code to clobber return register. */
7108 clobber_return_register ();
7112 after = emit_insn_after (seq, clobber_after);
7114 if (clobber_after != after)
7115 cfun->x_clobber_return_insn = after;
7118 /* ??? This should no longer be necessary since stupid is no longer with
7119 us, but there are some parts of the compiler (eg reload_combine, and
7120 sh mach_dep_reorg) that still try and compute their own lifetime info
7121 instead of using the general framework. */
7122 use_return_register ();
7124 /* Fix up any gotos that jumped out to the outermost
7125 binding level of the function.
7126 Must follow emitting RETURN_LABEL. */
7128 /* If you have any cleanups to do at this point,
7129 and they need to create temporary variables,
7130 then you will lose. */
7131 expand_fixups (get_insns ());
7135 get_arg_pointer_save_area (f)
7138 rtx ret = f->x_arg_pointer_save_area;
7142 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
7143 f->x_arg_pointer_save_area = ret;
7146 if (f == cfun && ! f->arg_pointer_save_area_init)
7150 /* Save the arg pointer at the beginning of the function. The
7151 generated stack slot may not be a valid memory address, so we
7152 have to check it and fix it if necessary. */
7154 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
7158 push_topmost_sequence ();
7159 emit_insn_after (seq, get_insns ());
7160 pop_topmost_sequence ();
7166 /* Extend a vector that records the INSN_UIDs of INSNS
7167 (a list of one or more insns). */
7170 record_insns (insns, vecp)
7179 while (tmp != NULL_RTX)
7182 tmp = NEXT_INSN (tmp);
7185 i = VARRAY_SIZE (*vecp);
7186 VARRAY_GROW (*vecp, i + len);
7188 while (tmp != NULL_RTX)
7190 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
7192 tmp = NEXT_INSN (tmp);
7196 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
7197 be running after reorg, SEQUENCE rtl is possible. */
7200 contains (insn, vec)
7206 if (GET_CODE (insn) == INSN
7207 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7210 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7211 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7212 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7218 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7219 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7226 prologue_epilogue_contains (insn)
7229 if (contains (insn, prologue))
7231 if (contains (insn, epilogue))
7237 sibcall_epilogue_contains (insn)
7240 if (sibcall_epilogue)
7241 return contains (insn, sibcall_epilogue);
7246 /* Insert gen_return at the end of block BB. This also means updating
7247 block_for_insn appropriately. */
7250 emit_return_into_block (bb, line_note)
7254 emit_jump_insn_after (gen_return (), bb->end);
7256 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
7257 NOTE_LINE_NUMBER (line_note), PREV_INSN (bb->end));
7259 #endif /* HAVE_return */
7261 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7263 /* These functions convert the epilogue into a variant that does not modify the
7264 stack pointer. This is used in cases where a function returns an object
7265 whose size is not known until it is computed. The called function leaves the
7266 object on the stack, leaves the stack depressed, and returns a pointer to
7269 What we need to do is track all modifications and references to the stack
7270 pointer, deleting the modifications and changing the references to point to
7271 the location the stack pointer would have pointed to had the modifications
7274 These functions need to be portable so we need to make as few assumptions
7275 about the epilogue as we can. However, the epilogue basically contains
7276 three things: instructions to reset the stack pointer, instructions to
7277 reload registers, possibly including the frame pointer, and an
7278 instruction to return to the caller.
7280 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7281 We also make no attempt to validate the insns we make since if they are
7282 invalid, we probably can't do anything valid. The intent is that these
7283 routines get "smarter" as more and more machines start to use them and
7284 they try operating on different epilogues.
7286 We use the following structure to track what the part of the epilogue that
7287 we've already processed has done. We keep two copies of the SP equivalence,
7288 one for use during the insn we are processing and one for use in the next
7289 insn. The difference is because one part of a PARALLEL may adjust SP
7290 and the other may use it. */
7294 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7295 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7296 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7297 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7298 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7299 should be set to once we no longer need
7303 static void handle_epilogue_set PARAMS ((rtx, struct epi_info *));
7304 static void emit_equiv_load PARAMS ((struct epi_info *));
7306 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
7307 no modifications to the stack pointer. Return the new list of insns. */
7310 keep_stack_depressed (insns)
7314 struct epi_info info;
7317 /* If the epilogue is just a single instruction, it ust be OK as is. */
7319 if (NEXT_INSN (insns) == NULL_RTX)
7322 /* Otherwise, start a sequence, initialize the information we have, and
7323 process all the insns we were given. */
7326 info.sp_equiv_reg = stack_pointer_rtx;
7328 info.equiv_reg_src = 0;
7332 while (insn != NULL_RTX)
7334 next = NEXT_INSN (insn);
7343 /* If this insn references the register that SP is equivalent to and
7344 we have a pending load to that register, we must force out the load
7345 first and then indicate we no longer know what SP's equivalent is. */
7346 if (info.equiv_reg_src != 0
7347 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7349 emit_equiv_load (&info);
7350 info.sp_equiv_reg = 0;
7353 info.new_sp_equiv_reg = info.sp_equiv_reg;
7354 info.new_sp_offset = info.sp_offset;
7356 /* If this is a (RETURN) and the return address is on the stack,
7357 update the address and change to an indirect jump. */
7358 if (GET_CODE (PATTERN (insn)) == RETURN
7359 || (GET_CODE (PATTERN (insn)) == PARALLEL
7360 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7362 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7364 HOST_WIDE_INT offset = 0;
7365 rtx jump_insn, jump_set;
7367 /* If the return address is in a register, we can emit the insn
7368 unchanged. Otherwise, it must be a MEM and we see what the
7369 base register and offset are. In any case, we have to emit any
7370 pending load to the equivalent reg of SP, if any. */
7371 if (GET_CODE (retaddr) == REG)
7373 emit_equiv_load (&info);
7378 else if (GET_CODE (retaddr) == MEM
7379 && GET_CODE (XEXP (retaddr, 0)) == REG)
7380 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7381 else if (GET_CODE (retaddr) == MEM
7382 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7383 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7384 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7386 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7387 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7392 /* If the base of the location containing the return pointer
7393 is SP, we must update it with the replacement address. Otherwise,
7394 just build the necessary MEM. */
7395 retaddr = plus_constant (base, offset);
7396 if (base == stack_pointer_rtx)
7397 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7398 plus_constant (info.sp_equiv_reg,
7401 retaddr = gen_rtx_MEM (Pmode, retaddr);
7403 /* If there is a pending load to the equivalent register for SP
7404 and we reference that register, we must load our address into
7405 a scratch register and then do that load. */
7406 if (info.equiv_reg_src
7407 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7412 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7413 if (HARD_REGNO_MODE_OK (regno, Pmode)
7414 && !fixed_regs[regno]
7415 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7416 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7418 && !refers_to_regno_p (regno,
7419 regno + HARD_REGNO_NREGS (regno,
7421 info.equiv_reg_src, NULL))
7424 if (regno == FIRST_PSEUDO_REGISTER)
7427 reg = gen_rtx_REG (Pmode, regno);
7428 emit_move_insn (reg, retaddr);
7432 emit_equiv_load (&info);
7433 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7435 /* Show the SET in the above insn is a RETURN. */
7436 jump_set = single_set (jump_insn);
7440 SET_IS_RETURN_P (jump_set) = 1;
7443 /* If SP is not mentioned in the pattern and its equivalent register, if
7444 any, is not modified, just emit it. Otherwise, if neither is set,
7445 replace the reference to SP and emit the insn. If none of those are
7446 true, handle each SET individually. */
7447 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7448 && (info.sp_equiv_reg == stack_pointer_rtx
7449 || !reg_set_p (info.sp_equiv_reg, insn)))
7451 else if (! reg_set_p (stack_pointer_rtx, insn)
7452 && (info.sp_equiv_reg == stack_pointer_rtx
7453 || !reg_set_p (info.sp_equiv_reg, insn)))
7455 if (! validate_replace_rtx (stack_pointer_rtx,
7456 plus_constant (info.sp_equiv_reg,
7463 else if (GET_CODE (PATTERN (insn)) == SET)
7464 handle_epilogue_set (PATTERN (insn), &info);
7465 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7467 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7468 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7469 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7474 info.sp_equiv_reg = info.new_sp_equiv_reg;
7475 info.sp_offset = info.new_sp_offset;
7480 insns = get_insns ();
7485 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7486 structure that contains information about what we've seen so far. We
7487 process this SET by either updating that data or by emitting one or
7491 handle_epilogue_set (set, p)
7495 /* First handle the case where we are setting SP. Record what it is being
7496 set from. If unknown, abort. */
7497 if (reg_set_p (stack_pointer_rtx, set))
7499 if (SET_DEST (set) != stack_pointer_rtx)
7502 if (GET_CODE (SET_SRC (set)) == PLUS
7503 && GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7505 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7506 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7509 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7511 /* If we are adjusting SP, we adjust from the old data. */
7512 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7514 p->new_sp_equiv_reg = p->sp_equiv_reg;
7515 p->new_sp_offset += p->sp_offset;
7518 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7524 /* Next handle the case where we are setting SP's equivalent register.
7525 If we already have a value to set it to, abort. We could update, but
7526 there seems little point in handling that case. Note that we have
7527 to allow for the case where we are setting the register set in
7528 the previous part of a PARALLEL inside a single insn. But use the
7529 old offset for any updates within this insn. */
7530 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7532 if (!rtx_equal_p (p->new_sp_equiv_reg, SET_DEST (set))
7533 || p->equiv_reg_src != 0)
7537 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7538 plus_constant (p->sp_equiv_reg,
7542 /* Otherwise, replace any references to SP in the insn to its new value
7543 and emit the insn. */
7546 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7547 plus_constant (p->sp_equiv_reg,
7549 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7550 plus_constant (p->sp_equiv_reg,
7556 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7562 if (p->equiv_reg_src != 0)
7563 emit_move_insn (p->sp_equiv_reg, p->equiv_reg_src);
7565 p->equiv_reg_src = 0;
7569 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7570 this into place with notes indicating where the prologue ends and where
7571 the epilogue begins. Update the basic block information when possible. */
7574 thread_prologue_and_epilogue_insns (f)
7575 rtx f ATTRIBUTE_UNUSED;
7579 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7582 #ifdef HAVE_prologue
7583 rtx prologue_end = NULL_RTX;
7585 #if defined (HAVE_epilogue) || defined(HAVE_return)
7586 rtx epilogue_end = NULL_RTX;
7589 #ifdef HAVE_prologue
7593 seq = gen_prologue ();
7596 /* Retain a map of the prologue insns. */
7597 record_insns (seq, &prologue);
7598 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
7603 /* Can't deal with multiple successors of the entry block
7604 at the moment. Function should always have at least one
7606 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7609 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7614 /* If the exit block has no non-fake predecessors, we don't need
7616 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7617 if ((e->flags & EDGE_FAKE) == 0)
7623 if (optimize && HAVE_return)
7625 /* If we're allowed to generate a simple return instruction,
7626 then by definition we don't need a full epilogue. Examine
7627 the block that falls through to EXIT. If it does not
7628 contain any code, examine its predecessors and try to
7629 emit (conditional) return instructions. */
7635 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7636 if (e->flags & EDGE_FALLTHRU)
7642 /* Verify that there are no active instructions in the last block. */
7644 while (label && GET_CODE (label) != CODE_LABEL)
7646 if (active_insn_p (label))
7648 label = PREV_INSN (label);
7651 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7653 rtx epilogue_line_note = NULL_RTX;
7655 /* Locate the line number associated with the closing brace,
7656 if we can find one. */
7657 for (seq = get_last_insn ();
7658 seq && ! active_insn_p (seq);
7659 seq = PREV_INSN (seq))
7660 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7662 epilogue_line_note = seq;
7666 for (e = last->pred; e; e = e_next)
7668 basic_block bb = e->src;
7671 e_next = e->pred_next;
7672 if (bb == ENTRY_BLOCK_PTR)
7676 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7679 /* If we have an unconditional jump, we can replace that
7680 with a simple return instruction. */
7681 if (simplejump_p (jump))
7683 emit_return_into_block (bb, epilogue_line_note);
7687 /* If we have a conditional jump, we can try to replace
7688 that with a conditional return instruction. */
7689 else if (condjump_p (jump))
7691 if (! redirect_jump (jump, 0, 0))
7694 /* If this block has only one successor, it both jumps
7695 and falls through to the fallthru block, so we can't
7697 if (bb->succ->succ_next == NULL)
7703 /* Fix up the CFG for the successful change we just made. */
7704 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7707 /* Emit a return insn for the exit fallthru block. Whether
7708 this is still reachable will be determined later. */
7710 emit_barrier_after (last->end);
7711 emit_return_into_block (last, epilogue_line_note);
7712 epilogue_end = last->end;
7713 last->succ->flags &= ~EDGE_FALLTHRU;
7718 #ifdef HAVE_epilogue
7721 /* Find the edge that falls through to EXIT. Other edges may exist
7722 due to RETURN instructions, but those don't need epilogues.
7723 There really shouldn't be a mixture -- either all should have
7724 been converted or none, however... */
7726 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7727 if (e->flags & EDGE_FALLTHRU)
7733 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
7735 seq = gen_epilogue ();
7737 #ifdef INCOMING_RETURN_ADDR_RTX
7738 /* If this function returns with the stack depressed and we can support
7739 it, massage the epilogue to actually do that. */
7740 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7741 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7742 seq = keep_stack_depressed (seq);
7745 emit_jump_insn (seq);
7747 /* Retain a map of the epilogue insns. */
7748 record_insns (seq, &epilogue);
7753 insert_insn_on_edge (seq, e);
7760 commit_edge_insertions ();
7762 #ifdef HAVE_sibcall_epilogue
7763 /* Emit sibling epilogues before any sibling call sites. */
7764 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7766 basic_block bb = e->src;
7771 if (GET_CODE (insn) != CALL_INSN
7772 || ! SIBLING_CALL_P (insn))
7776 emit_insn (gen_sibcall_epilogue ());
7780 /* Retain a map of the epilogue insns. Used in life analysis to
7781 avoid getting rid of sibcall epilogue insns. Do this before we
7782 actually emit the sequence. */
7783 record_insns (seq, &sibcall_epilogue);
7785 i = PREV_INSN (insn);
7786 newinsn = emit_insn_before (seq, insn);
7790 #ifdef HAVE_prologue
7795 /* GDB handles `break f' by setting a breakpoint on the first
7796 line note after the prologue. Which means (1) that if
7797 there are line number notes before where we inserted the
7798 prologue we should move them, and (2) we should generate a
7799 note before the end of the first basic block, if there isn't
7802 ??? This behavior is completely broken when dealing with
7803 multiple entry functions. We simply place the note always
7804 into first basic block and let alternate entry points
7808 for (insn = prologue_end; insn; insn = prev)
7810 prev = PREV_INSN (insn);
7811 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7813 /* Note that we cannot reorder the first insn in the
7814 chain, since rest_of_compilation relies on that
7815 remaining constant. */
7818 reorder_insns (insn, insn, prologue_end);
7822 /* Find the last line number note in the first block. */
7823 for (insn = ENTRY_BLOCK_PTR->next_bb->end;
7824 insn != prologue_end && insn;
7825 insn = PREV_INSN (insn))
7826 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7829 /* If we didn't find one, make a copy of the first line number
7833 for (insn = next_active_insn (prologue_end);
7835 insn = PREV_INSN (insn))
7836 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7838 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7839 NOTE_LINE_NUMBER (insn),
7846 #ifdef HAVE_epilogue
7851 /* Similarly, move any line notes that appear after the epilogue.
7852 There is no need, however, to be quite so anal about the existence
7854 for (insn = epilogue_end; insn; insn = next)
7856 next = NEXT_INSN (insn);
7857 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7858 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7864 /* Reposition the prologue-end and epilogue-begin notes after instruction
7865 scheduling and delayed branch scheduling. */
7868 reposition_prologue_and_epilogue_notes (f)
7869 rtx f ATTRIBUTE_UNUSED;
7871 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7872 rtx insn, last, note;
7875 if ((len = VARRAY_SIZE (prologue)) > 0)
7879 /* Scan from the beginning until we reach the last prologue insn.
7880 We apparently can't depend on basic_block_{head,end} after
7882 for (insn = f; insn; insn = NEXT_INSN (insn))
7884 if (GET_CODE (insn) == NOTE)
7886 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7889 else if (contains (insn, prologue))
7899 /* Find the prologue-end note if we haven't already, and
7900 move it to just after the last prologue insn. */
7903 for (note = last; (note = NEXT_INSN (note));)
7904 if (GET_CODE (note) == NOTE
7905 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7909 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7910 if (GET_CODE (last) == CODE_LABEL)
7911 last = NEXT_INSN (last);
7912 reorder_insns (note, note, last);
7916 if ((len = VARRAY_SIZE (epilogue)) > 0)
7920 /* Scan from the end until we reach the first epilogue insn.
7921 We apparently can't depend on basic_block_{head,end} after
7923 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
7925 if (GET_CODE (insn) == NOTE)
7927 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7930 else if (contains (insn, epilogue))
7940 /* Find the epilogue-begin note if we haven't already, and
7941 move it to just before the first epilogue insn. */
7944 for (note = insn; (note = PREV_INSN (note));)
7945 if (GET_CODE (note) == NOTE
7946 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7950 if (PREV_INSN (last) != note)
7951 reorder_insns (note, note, PREV_INSN (last));
7954 #endif /* HAVE_prologue or HAVE_epilogue */
7957 /* Called once, at initialization, to initialize function.c. */
7960 init_function_once ()
7962 VARRAY_INT_INIT (prologue, 0, "prologue");
7963 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7964 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
7967 #include "gt-function.h"