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,
286 static void purge_single_hard_subreg_set PARAMS ((rtx));
287 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
288 static rtx keep_stack_depressed PARAMS ((rtx));
290 static int is_addressof PARAMS ((rtx *, void *));
291 static hashval_t insns_for_mem_hash PARAMS ((const void *));
292 static int insns_for_mem_comp PARAMS ((const void *, const void *));
293 static int insns_for_mem_walk PARAMS ((rtx *, void *));
294 static void compute_insns_for_mem PARAMS ((rtx, rtx, htab_t));
295 static void prepare_function_start PARAMS ((void));
296 static void do_clobber_return_reg PARAMS ((rtx, void *));
297 static void do_use_return_reg PARAMS ((rtx, void *));
298 static void instantiate_virtual_regs_lossage PARAMS ((rtx));
300 /* Pointer to chain of `struct function' for containing functions. */
301 static GTY(()) struct function *outer_function_chain;
303 /* Given a function decl for a containing function,
304 return the `struct function' for it. */
307 find_function_data (decl)
312 for (p = outer_function_chain; p; p = p->outer)
319 /* Save the current context for compilation of a nested function.
320 This is called from language-specific code. The caller should use
321 the enter_nested langhook to save any language-specific state,
322 since this function knows only about language-independent
326 push_function_context_to (context)
333 if (context == current_function_decl)
334 cfun->contains_functions = 1;
337 struct function *containing = find_function_data (context);
338 containing->contains_functions = 1;
343 init_dummy_function_start ();
346 p->outer = outer_function_chain;
347 outer_function_chain = p;
348 p->fixup_var_refs_queue = 0;
350 (*lang_hooks.function.enter_nested) (p);
356 push_function_context ()
358 push_function_context_to (current_function_decl);
361 /* Restore the last saved context, at the end of a nested function.
362 This function is called from language-specific code. */
365 pop_function_context_from (context)
366 tree context ATTRIBUTE_UNUSED;
368 struct function *p = outer_function_chain;
369 struct var_refs_queue *queue;
372 outer_function_chain = p->outer;
374 current_function_decl = p->decl;
377 restore_emit_status (p);
379 (*lang_hooks.function.leave_nested) (p);
381 /* Finish doing put_var_into_stack for any of our variables which became
382 addressable during the nested function. If only one entry has to be
383 fixed up, just do that one. Otherwise, first make a list of MEMs that
384 are not to be unshared. */
385 if (p->fixup_var_refs_queue == 0)
387 else if (p->fixup_var_refs_queue->next == 0)
388 fixup_var_refs (p->fixup_var_refs_queue->modified,
389 p->fixup_var_refs_queue->promoted_mode,
390 p->fixup_var_refs_queue->unsignedp,
391 p->fixup_var_refs_queue->modified, 0);
396 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
397 list = gen_rtx_EXPR_LIST (VOIDmode, queue->modified, list);
399 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
400 fixup_var_refs (queue->modified, queue->promoted_mode,
401 queue->unsignedp, list, 0);
405 p->fixup_var_refs_queue = 0;
407 /* Reset variables that have known state during rtx generation. */
408 rtx_equal_function_value_matters = 1;
409 virtuals_instantiated = 0;
410 generating_concat_p = 1;
414 pop_function_context ()
416 pop_function_context_from (current_function_decl);
419 /* Clear out all parts of the state in F that can safely be discarded
420 after the function has been parsed, but not compiled, to let
421 garbage collection reclaim the memory. */
424 free_after_parsing (f)
427 /* f->expr->forced_labels is used by code generation. */
428 /* f->emit->regno_reg_rtx is used by code generation. */
429 /* f->varasm is used by code generation. */
430 /* f->eh->eh_return_stub_label is used by code generation. */
432 (*lang_hooks.function.final) (f);
436 /* Clear out all parts of the state in F that can safely be discarded
437 after the function has been compiled, to let garbage collection
438 reclaim the memory. */
441 free_after_compilation (f)
450 f->x_temp_slots = NULL;
451 f->arg_offset_rtx = NULL;
452 f->return_rtx = NULL;
453 f->internal_arg_pointer = NULL;
454 f->x_nonlocal_labels = NULL;
455 f->x_nonlocal_goto_handler_slots = NULL;
456 f->x_nonlocal_goto_handler_labels = NULL;
457 f->x_nonlocal_goto_stack_level = NULL;
458 f->x_cleanup_label = NULL;
459 f->x_return_label = NULL;
460 f->computed_goto_common_label = NULL;
461 f->computed_goto_common_reg = NULL;
462 f->x_save_expr_regs = NULL;
463 f->x_stack_slot_list = NULL;
464 f->x_rtl_expr_chain = NULL;
465 f->x_tail_recursion_label = NULL;
466 f->x_tail_recursion_reentry = NULL;
467 f->x_arg_pointer_save_area = NULL;
468 f->x_clobber_return_insn = NULL;
469 f->x_context_display = NULL;
470 f->x_trampoline_list = NULL;
471 f->x_parm_birth_insn = NULL;
472 f->x_last_parm_insn = NULL;
473 f->x_parm_reg_stack_loc = NULL;
474 f->fixup_var_refs_queue = NULL;
475 f->original_arg_vector = NULL;
476 f->original_decl_initial = NULL;
477 f->inl_last_parm_insn = NULL;
478 f->epilogue_delay_list = NULL;
481 /* Allocate fixed slots in the stack frame of the current function. */
483 /* Return size needed for stack frame based on slots so far allocated in
485 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
486 the caller may have to do that. */
489 get_func_frame_size (f)
492 #ifdef FRAME_GROWS_DOWNWARD
493 return -f->x_frame_offset;
495 return f->x_frame_offset;
499 /* Return size needed for stack frame based on slots so far allocated.
500 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
501 the caller may have to do that. */
505 return get_func_frame_size (cfun);
508 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
509 with machine mode MODE.
511 ALIGN controls the amount of alignment for the address of the slot:
512 0 means according to MODE,
513 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
514 positive specifies alignment boundary in bits.
516 We do not round to stack_boundary here.
518 FUNCTION specifies the function to allocate in. */
521 assign_stack_local_1 (mode, size, align, function)
522 enum machine_mode mode;
525 struct function *function;
528 int bigend_correction = 0;
530 int frame_off, frame_alignment, frame_phase;
537 alignment = BIGGEST_ALIGNMENT;
539 alignment = GET_MODE_ALIGNMENT (mode);
541 /* Allow the target to (possibly) increase the alignment of this
543 type = (*lang_hooks.types.type_for_mode) (mode, 0);
545 alignment = LOCAL_ALIGNMENT (type, alignment);
547 alignment /= BITS_PER_UNIT;
549 else if (align == -1)
551 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
552 size = CEIL_ROUND (size, alignment);
555 alignment = align / BITS_PER_UNIT;
557 #ifdef FRAME_GROWS_DOWNWARD
558 function->x_frame_offset -= size;
561 /* Ignore alignment we can't do with expected alignment of the boundary. */
562 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
563 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
565 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
566 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
568 /* Calculate how many bytes the start of local variables is off from
570 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
571 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
572 frame_phase = frame_off ? frame_alignment - frame_off : 0;
574 /* Round the frame offset to the specified alignment. The default is
575 to always honor requests to align the stack but a port may choose to
576 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
577 if (STACK_ALIGNMENT_NEEDED
581 /* We must be careful here, since FRAME_OFFSET might be negative and
582 division with a negative dividend isn't as well defined as we might
583 like. So we instead assume that ALIGNMENT is a power of two and
584 use logical operations which are unambiguous. */
585 #ifdef FRAME_GROWS_DOWNWARD
586 function->x_frame_offset
587 = (FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment)
590 function->x_frame_offset
591 = (CEIL_ROUND (function->x_frame_offset - frame_phase, alignment)
596 /* On a big-endian machine, if we are allocating more space than we will use,
597 use the least significant bytes of those that are allocated. */
598 if (BYTES_BIG_ENDIAN && mode != BLKmode)
599 bigend_correction = size - GET_MODE_SIZE (mode);
601 /* If we have already instantiated virtual registers, return the actual
602 address relative to the frame pointer. */
603 if (function == cfun && virtuals_instantiated)
604 addr = plus_constant (frame_pointer_rtx,
606 (frame_offset + bigend_correction
607 + STARTING_FRAME_OFFSET, Pmode));
609 addr = plus_constant (virtual_stack_vars_rtx,
611 (function->x_frame_offset + bigend_correction,
614 #ifndef FRAME_GROWS_DOWNWARD
615 function->x_frame_offset += size;
618 x = gen_rtx_MEM (mode, addr);
620 function->x_stack_slot_list
621 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
626 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
630 assign_stack_local (mode, size, align)
631 enum machine_mode mode;
635 return assign_stack_local_1 (mode, size, align, cfun);
638 /* Allocate a temporary stack slot and record it for possible later
641 MODE is the machine mode to be given to the returned rtx.
643 SIZE is the size in units of the space required. We do no rounding here
644 since assign_stack_local will do any required rounding.
646 KEEP is 1 if this slot is to be retained after a call to
647 free_temp_slots. Automatic variables for a block are allocated
648 with this flag. KEEP is 2 if we allocate a longer term temporary,
649 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
650 if we are to allocate something at an inner level to be treated as
651 a variable in the block (e.g., a SAVE_EXPR).
653 TYPE is the type that will be used for the stack slot. */
656 assign_stack_temp_for_type (mode, size, keep, type)
657 enum machine_mode mode;
663 struct temp_slot *p, *best_p = 0;
666 /* If SIZE is -1 it means that somebody tried to allocate a temporary
667 of a variable size. */
672 align = BIGGEST_ALIGNMENT;
674 align = GET_MODE_ALIGNMENT (mode);
677 type = (*lang_hooks.types.type_for_mode) (mode, 0);
680 align = LOCAL_ALIGNMENT (type, align);
682 /* Try to find an available, already-allocated temporary of the proper
683 mode which meets the size and alignment requirements. Choose the
684 smallest one with the closest alignment. */
685 for (p = temp_slots; p; p = p->next)
686 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
688 && objects_must_conflict_p (p->type, type)
689 && (best_p == 0 || best_p->size > p->size
690 || (best_p->size == p->size && best_p->align > p->align)))
692 if (p->align == align && p->size == size)
700 /* Make our best, if any, the one to use. */
703 /* If there are enough aligned bytes left over, make them into a new
704 temp_slot so that the extra bytes don't get wasted. Do this only
705 for BLKmode slots, so that we can be sure of the alignment. */
706 if (GET_MODE (best_p->slot) == BLKmode)
708 int alignment = best_p->align / BITS_PER_UNIT;
709 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
711 if (best_p->size - rounded_size >= alignment)
713 p = (struct temp_slot *) ggc_alloc (sizeof (struct temp_slot));
714 p->in_use = p->addr_taken = 0;
715 p->size = best_p->size - rounded_size;
716 p->base_offset = best_p->base_offset + rounded_size;
717 p->full_size = best_p->full_size - rounded_size;
718 p->slot = gen_rtx_MEM (BLKmode,
719 plus_constant (XEXP (best_p->slot, 0),
721 p->align = best_p->align;
724 p->type = best_p->type;
725 p->next = temp_slots;
728 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
731 best_p->size = rounded_size;
732 best_p->full_size = rounded_size;
739 /* If we still didn't find one, make a new temporary. */
742 HOST_WIDE_INT frame_offset_old = frame_offset;
744 p = (struct temp_slot *) ggc_alloc (sizeof (struct temp_slot));
746 /* We are passing an explicit alignment request to assign_stack_local.
747 One side effect of that is assign_stack_local will not round SIZE
748 to ensure the frame offset remains suitably aligned.
750 So for requests which depended on the rounding of SIZE, we go ahead
751 and round it now. We also make sure ALIGNMENT is at least
752 BIGGEST_ALIGNMENT. */
753 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
755 p->slot = assign_stack_local (mode,
757 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
763 /* The following slot size computation is necessary because we don't
764 know the actual size of the temporary slot until assign_stack_local
765 has performed all the frame alignment and size rounding for the
766 requested temporary. Note that extra space added for alignment
767 can be either above or below this stack slot depending on which
768 way the frame grows. We include the extra space if and only if it
769 is above this slot. */
770 #ifdef FRAME_GROWS_DOWNWARD
771 p->size = frame_offset_old - frame_offset;
776 /* Now define the fields used by combine_temp_slots. */
777 #ifdef FRAME_GROWS_DOWNWARD
778 p->base_offset = frame_offset;
779 p->full_size = frame_offset_old - frame_offset;
781 p->base_offset = frame_offset_old;
782 p->full_size = frame_offset - frame_offset_old;
785 p->next = temp_slots;
791 p->rtl_expr = seq_rtl_expr;
796 p->level = target_temp_slot_level;
801 p->level = var_temp_slot_level;
806 p->level = temp_slot_level;
811 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
812 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
813 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
815 /* If we know the alias set for the memory that will be used, use
816 it. If there's no TYPE, then we don't know anything about the
817 alias set for the memory. */
818 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
819 set_mem_align (slot, align);
821 /* If a type is specified, set the relevant flags. */
824 RTX_UNCHANGING_P (slot) = (lang_hooks.honor_readonly
825 && TYPE_READONLY (type));
826 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
827 MEM_SET_IN_STRUCT_P (slot, AGGREGATE_TYPE_P (type));
833 /* Allocate a temporary stack slot and record it for possible later
834 reuse. First three arguments are same as in preceding function. */
837 assign_stack_temp (mode, size, keep)
838 enum machine_mode mode;
842 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
845 /* Assign a temporary.
846 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
847 and so that should be used in error messages. In either case, we
848 allocate of the given type.
849 KEEP is as for assign_stack_temp.
850 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
851 it is 0 if a register is OK.
852 DONT_PROMOTE is 1 if we should not promote values in register
856 assign_temp (type_or_decl, keep, memory_required, dont_promote)
860 int dont_promote ATTRIBUTE_UNUSED;
863 enum machine_mode mode;
864 #ifndef PROMOTE_FOR_CALL_ONLY
868 if (DECL_P (type_or_decl))
869 decl = type_or_decl, type = TREE_TYPE (decl);
871 decl = NULL, type = type_or_decl;
873 mode = TYPE_MODE (type);
874 #ifndef PROMOTE_FOR_CALL_ONLY
875 unsignedp = TREE_UNSIGNED (type);
878 if (mode == BLKmode || memory_required)
880 HOST_WIDE_INT size = int_size_in_bytes (type);
883 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
884 problems with allocating the stack space. */
888 /* Unfortunately, we don't yet know how to allocate variable-sized
889 temporaries. However, sometimes we have a fixed upper limit on
890 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
891 instead. This is the case for Chill variable-sized strings. */
892 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
893 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
894 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
895 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
897 /* The size of the temporary may be too large to fit into an integer. */
898 /* ??? Not sure this should happen except for user silliness, so limit
899 this to things that aren't compiler-generated temporaries. The
900 rest of the time we'll abort in assign_stack_temp_for_type. */
901 if (decl && size == -1
902 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
904 error_with_decl (decl, "size of variable `%s' is too large");
908 tmp = assign_stack_temp_for_type (mode, size, keep, type);
912 #ifndef PROMOTE_FOR_CALL_ONLY
914 mode = promote_mode (type, mode, &unsignedp, 0);
917 return gen_reg_rtx (mode);
920 /* Combine temporary stack slots which are adjacent on the stack.
922 This allows for better use of already allocated stack space. This is only
923 done for BLKmode slots because we can be sure that we won't have alignment
924 problems in this case. */
927 combine_temp_slots ()
929 struct temp_slot *p, *q;
930 struct temp_slot *prev_p, *prev_q;
933 /* We can't combine slots, because the information about which slot
934 is in which alias set will be lost. */
935 if (flag_strict_aliasing)
938 /* If there are a lot of temp slots, don't do anything unless
939 high levels of optimization. */
940 if (! flag_expensive_optimizations)
941 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
942 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
945 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
949 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
950 for (q = p->next, prev_q = p; q; q = prev_q->next)
953 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
955 if (p->base_offset + p->full_size == q->base_offset)
957 /* Q comes after P; combine Q into P. */
959 p->full_size += q->full_size;
962 else if (q->base_offset + q->full_size == p->base_offset)
964 /* P comes after Q; combine P into Q. */
966 q->full_size += p->full_size;
971 /* Either delete Q or advance past it. */
973 prev_q->next = q->next;
977 /* Either delete P or advance past it. */
981 prev_p->next = p->next;
983 temp_slots = p->next;
990 /* Find the temp slot corresponding to the object at address X. */
992 static struct temp_slot *
993 find_temp_slot_from_address (x)
999 for (p = temp_slots; p; p = p->next)
1004 else if (XEXP (p->slot, 0) == x
1006 || (GET_CODE (x) == PLUS
1007 && XEXP (x, 0) == virtual_stack_vars_rtx
1008 && GET_CODE (XEXP (x, 1)) == CONST_INT
1009 && INTVAL (XEXP (x, 1)) >= p->base_offset
1010 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
1013 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
1014 for (next = p->address; next; next = XEXP (next, 1))
1015 if (XEXP (next, 0) == x)
1019 /* If we have a sum involving a register, see if it points to a temp
1021 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
1022 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
1024 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
1025 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1031 /* Indicate that NEW is an alternate way of referring to the temp slot
1032 that previously was known by OLD. */
1035 update_temp_slot_address (old, new)
1038 struct temp_slot *p;
1040 if (rtx_equal_p (old, new))
1043 p = find_temp_slot_from_address (old);
1045 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1046 is a register, see if one operand of the PLUS is a temporary
1047 location. If so, NEW points into it. Otherwise, if both OLD and
1048 NEW are a PLUS and if there is a register in common between them.
1049 If so, try a recursive call on those values. */
1052 if (GET_CODE (old) != PLUS)
1055 if (GET_CODE (new) == REG)
1057 update_temp_slot_address (XEXP (old, 0), new);
1058 update_temp_slot_address (XEXP (old, 1), new);
1061 else if (GET_CODE (new) != PLUS)
1064 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1065 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1066 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1067 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1068 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1069 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1070 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1071 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1076 /* Otherwise add an alias for the temp's address. */
1077 else if (p->address == 0)
1081 if (GET_CODE (p->address) != EXPR_LIST)
1082 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1084 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1088 /* If X could be a reference to a temporary slot, mark the fact that its
1089 address was taken. */
1092 mark_temp_addr_taken (x)
1095 struct temp_slot *p;
1100 /* If X is not in memory or is at a constant address, it cannot be in
1101 a temporary slot. */
1102 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1105 p = find_temp_slot_from_address (XEXP (x, 0));
1110 /* If X could be a reference to a temporary slot, mark that slot as
1111 belonging to the to one level higher than the current level. If X
1112 matched one of our slots, just mark that one. Otherwise, we can't
1113 easily predict which it is, so upgrade all of them. Kept slots
1114 need not be touched.
1116 This is called when an ({...}) construct occurs and a statement
1117 returns a value in memory. */
1120 preserve_temp_slots (x)
1123 struct temp_slot *p = 0;
1125 /* If there is no result, we still might have some objects whose address
1126 were taken, so we need to make sure they stay around. */
1129 for (p = temp_slots; p; p = p->next)
1130 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1136 /* If X is a register that is being used as a pointer, see if we have
1137 a temporary slot we know it points to. To be consistent with
1138 the code below, we really should preserve all non-kept slots
1139 if we can't find a match, but that seems to be much too costly. */
1140 if (GET_CODE (x) == REG && REG_POINTER (x))
1141 p = find_temp_slot_from_address (x);
1143 /* If X is not in memory or is at a constant address, it cannot be in
1144 a temporary slot, but it can contain something whose address was
1146 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1148 for (p = temp_slots; p; p = p->next)
1149 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1155 /* First see if we can find a match. */
1157 p = find_temp_slot_from_address (XEXP (x, 0));
1161 /* Move everything at our level whose address was taken to our new
1162 level in case we used its address. */
1163 struct temp_slot *q;
1165 if (p->level == temp_slot_level)
1167 for (q = temp_slots; q; q = q->next)
1168 if (q != p && q->addr_taken && q->level == p->level)
1177 /* Otherwise, preserve all non-kept slots at this level. */
1178 for (p = temp_slots; p; p = p->next)
1179 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1183 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1184 with that RTL_EXPR, promote it into a temporary slot at the present
1185 level so it will not be freed when we free slots made in the
1189 preserve_rtl_expr_result (x)
1192 struct temp_slot *p;
1194 /* If X is not in memory or is at a constant address, it cannot be in
1195 a temporary slot. */
1196 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1199 /* If we can find a match, move it to our level unless it is already at
1201 p = find_temp_slot_from_address (XEXP (x, 0));
1204 p->level = MIN (p->level, temp_slot_level);
1211 /* Free all temporaries used so far. This is normally called at the end
1212 of generating code for a statement. Don't free any temporaries
1213 currently in use for an RTL_EXPR that hasn't yet been emitted.
1214 We could eventually do better than this since it can be reused while
1215 generating the same RTL_EXPR, but this is complex and probably not
1221 struct temp_slot *p;
1223 for (p = temp_slots; p; p = p->next)
1224 if (p->in_use && p->level == temp_slot_level && ! p->keep
1225 && p->rtl_expr == 0)
1228 combine_temp_slots ();
1231 /* Free all temporary slots used in T, an RTL_EXPR node. */
1234 free_temps_for_rtl_expr (t)
1237 struct temp_slot *p;
1239 for (p = temp_slots; p; p = p->next)
1240 if (p->rtl_expr == t)
1242 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1243 needs to be preserved. This can happen if a temporary in
1244 the RTL_EXPR was addressed; preserve_temp_slots will move
1245 the temporary into a higher level. */
1246 if (temp_slot_level <= p->level)
1249 p->rtl_expr = NULL_TREE;
1252 combine_temp_slots ();
1255 /* Mark all temporaries ever allocated in this function as not suitable
1256 for reuse until the current level is exited. */
1259 mark_all_temps_used ()
1261 struct temp_slot *p;
1263 for (p = temp_slots; p; p = p->next)
1265 p->in_use = p->keep = 1;
1266 p->level = MIN (p->level, temp_slot_level);
1270 /* Push deeper into the nesting level for stack temporaries. */
1278 /* Pop a temporary nesting level. All slots in use in the current level
1284 struct temp_slot *p;
1286 for (p = temp_slots; p; p = p->next)
1287 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1290 combine_temp_slots ();
1295 /* Initialize temporary slots. */
1300 /* We have not allocated any temporaries yet. */
1302 temp_slot_level = 0;
1303 var_temp_slot_level = 0;
1304 target_temp_slot_level = 0;
1307 /* Retroactively move an auto variable from a register to a stack
1308 slot. This is done when an address-reference to the variable is
1309 seen. If RESCAN is true, all previously emitted instructions are
1310 examined and modified to handle the fact that DECL is now
1314 put_var_into_stack (decl, rescan)
1319 enum machine_mode promoted_mode, decl_mode;
1320 struct function *function = 0;
1322 int can_use_addressof;
1323 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1324 int usedp = (TREE_USED (decl)
1325 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1327 context = decl_function_context (decl);
1329 /* Get the current rtl used for this object and its original mode. */
1330 reg = (TREE_CODE (decl) == SAVE_EXPR
1331 ? SAVE_EXPR_RTL (decl)
1332 : DECL_RTL_IF_SET (decl));
1334 /* No need to do anything if decl has no rtx yet
1335 since in that case caller is setting TREE_ADDRESSABLE
1336 and a stack slot will be assigned when the rtl is made. */
1340 /* Get the declared mode for this object. */
1341 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1342 : DECL_MODE (decl));
1343 /* Get the mode it's actually stored in. */
1344 promoted_mode = GET_MODE (reg);
1346 /* If this variable comes from an outer function, find that
1347 function's saved context. Don't use find_function_data here,
1348 because it might not be in any active function.
1349 FIXME: Is that really supposed to happen?
1350 It does in ObjC at least. */
1351 if (context != current_function_decl && context != inline_function_decl)
1352 for (function = outer_function_chain; function; function = function->outer)
1353 if (function->decl == context)
1356 /* If this is a variable-size object with a pseudo to address it,
1357 put that pseudo into the stack, if the var is nonlocal. */
1358 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1359 && GET_CODE (reg) == MEM
1360 && GET_CODE (XEXP (reg, 0)) == REG
1361 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1363 reg = XEXP (reg, 0);
1364 decl_mode = promoted_mode = GET_MODE (reg);
1370 /* FIXME make it work for promoted modes too */
1371 && decl_mode == promoted_mode
1372 #ifdef NON_SAVING_SETJMP
1373 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1377 /* If we can't use ADDRESSOF, make sure we see through one we already
1379 if (! can_use_addressof && GET_CODE (reg) == MEM
1380 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1381 reg = XEXP (XEXP (reg, 0), 0);
1383 /* Now we should have a value that resides in one or more pseudo regs. */
1385 if (GET_CODE (reg) == REG)
1387 /* If this variable lives in the current function and we don't need
1388 to put things in the stack for the sake of setjmp, try to keep it
1389 in a register until we know we actually need the address. */
1390 if (can_use_addressof)
1391 gen_mem_addressof (reg, decl, rescan);
1393 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1394 decl_mode, volatilep, 0, usedp, 0);
1396 else if (GET_CODE (reg) == CONCAT)
1398 /* A CONCAT contains two pseudos; put them both in the stack.
1399 We do it so they end up consecutive.
1400 We fixup references to the parts only after we fixup references
1401 to the whole CONCAT, lest we do double fixups for the latter
1403 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1404 tree part_type = (*lang_hooks.types.type_for_mode) (part_mode, 0);
1405 rtx lopart = XEXP (reg, 0);
1406 rtx hipart = XEXP (reg, 1);
1407 #ifdef FRAME_GROWS_DOWNWARD
1408 /* Since part 0 should have a lower address, do it second. */
1409 put_reg_into_stack (function, hipart, part_type, part_mode,
1410 part_mode, volatilep, 0, 0, 0);
1411 put_reg_into_stack (function, lopart, part_type, part_mode,
1412 part_mode, volatilep, 0, 0, 0);
1414 put_reg_into_stack (function, lopart, part_type, part_mode,
1415 part_mode, volatilep, 0, 0, 0);
1416 put_reg_into_stack (function, hipart, part_type, part_mode,
1417 part_mode, volatilep, 0, 0, 0);
1420 /* Change the CONCAT into a combined MEM for both parts. */
1421 PUT_CODE (reg, MEM);
1422 MEM_ATTRS (reg) = 0;
1424 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1425 already computed alias sets. Here we want to re-generate. */
1427 SET_DECL_RTL (decl, NULL);
1428 set_mem_attributes (reg, decl, 1);
1430 SET_DECL_RTL (decl, reg);
1432 /* The two parts are in memory order already.
1433 Use the lower parts address as ours. */
1434 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1435 /* Prevent sharing of rtl that might lose. */
1436 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1437 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1438 if (usedp && rescan)
1440 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1442 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1443 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1450 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1451 into the stack frame of FUNCTION (0 means the current function).
1452 DECL_MODE is the machine mode of the user-level data type.
1453 PROMOTED_MODE is the machine mode of the register.
1454 VOLATILE_P is nonzero if this is for a "volatile" decl.
1455 USED_P is nonzero if this reg might have already been used in an insn. */
1458 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1459 original_regno, used_p, ht)
1460 struct function *function;
1463 enum machine_mode promoted_mode, decl_mode;
1465 unsigned int original_regno;
1469 struct function *func = function ? function : cfun;
1471 unsigned int regno = original_regno;
1474 regno = REGNO (reg);
1476 if (regno < func->x_max_parm_reg)
1477 new = func->x_parm_reg_stack_loc[regno];
1480 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1482 PUT_CODE (reg, MEM);
1483 PUT_MODE (reg, decl_mode);
1484 XEXP (reg, 0) = XEXP (new, 0);
1485 MEM_ATTRS (reg) = 0;
1486 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1487 MEM_VOLATILE_P (reg) = volatile_p;
1489 /* If this is a memory ref that contains aggregate components,
1490 mark it as such for cse and loop optimize. If we are reusing a
1491 previously generated stack slot, then we need to copy the bit in
1492 case it was set for other reasons. For instance, it is set for
1493 __builtin_va_alist. */
1496 MEM_SET_IN_STRUCT_P (reg,
1497 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1498 set_mem_alias_set (reg, get_alias_set (type));
1502 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1505 /* Make sure that all refs to the variable, previously made
1506 when it was a register, are fixed up to be valid again.
1507 See function above for meaning of arguments. */
1510 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht)
1511 struct function *function;
1514 enum machine_mode promoted_mode;
1517 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1521 struct var_refs_queue *temp;
1524 = (struct var_refs_queue *) ggc_alloc (sizeof (struct var_refs_queue));
1525 temp->modified = reg;
1526 temp->promoted_mode = promoted_mode;
1527 temp->unsignedp = unsigned_p;
1528 temp->next = function->fixup_var_refs_queue;
1529 function->fixup_var_refs_queue = temp;
1532 /* Variable is local; fix it up now. */
1533 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht);
1537 fixup_var_refs (var, promoted_mode, unsignedp, may_share, ht)
1539 enum machine_mode promoted_mode;
1545 rtx first_insn = get_insns ();
1546 struct sequence_stack *stack = seq_stack;
1547 tree rtl_exps = rtl_expr_chain;
1549 /* If there's a hash table, it must record all uses of VAR. */
1554 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp,
1559 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1560 stack == 0, may_share);
1562 /* Scan all pending sequences too. */
1563 for (; stack; stack = stack->next)
1565 push_to_full_sequence (stack->first, stack->last);
1566 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1567 stack->next != 0, may_share);
1568 /* Update remembered end of sequence
1569 in case we added an insn at the end. */
1570 stack->last = get_last_insn ();
1574 /* Scan all waiting RTL_EXPRs too. */
1575 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1577 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1578 if (seq != const0_rtx && seq != 0)
1580 push_to_sequence (seq);
1581 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1588 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1589 some part of an insn. Return a struct fixup_replacement whose OLD
1590 value is equal to X. Allocate a new structure if no such entry exists. */
1592 static struct fixup_replacement *
1593 find_fixup_replacement (replacements, x)
1594 struct fixup_replacement **replacements;
1597 struct fixup_replacement *p;
1599 /* See if we have already replaced this. */
1600 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1605 p = (struct fixup_replacement *) xmalloc (sizeof (struct fixup_replacement));
1608 p->next = *replacements;
1615 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1616 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1617 for the current function. MAY_SHARE is either a MEM that is not
1618 to be unshared or a list of them. */
1621 fixup_var_refs_insns (insn, var, promoted_mode, unsignedp, toplevel, may_share)
1624 enum machine_mode promoted_mode;
1631 /* fixup_var_refs_insn might modify insn, so save its next
1633 rtx next = NEXT_INSN (insn);
1635 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1636 the three sequences they (potentially) contain, and process
1637 them recursively. The CALL_INSN itself is not interesting. */
1639 if (GET_CODE (insn) == CALL_INSN
1640 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1644 /* Look at the Normal call, sibling call and tail recursion
1645 sequences attached to the CALL_PLACEHOLDER. */
1646 for (i = 0; i < 3; i++)
1648 rtx seq = XEXP (PATTERN (insn), i);
1651 push_to_sequence (seq);
1652 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1654 XEXP (PATTERN (insn), i) = get_insns ();
1660 else if (INSN_P (insn))
1661 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel,
1668 /* Look up the insns which reference VAR in HT and fix them up. Other
1669 arguments are the same as fixup_var_refs_insns.
1671 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1672 because the hash table will point straight to the interesting insn
1673 (inside the CALL_PLACEHOLDER). */
1676 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp, may_share)
1679 enum machine_mode promoted_mode;
1683 struct insns_for_mem_entry tmp;
1684 struct insns_for_mem_entry *ime;
1688 ime = (struct insns_for_mem_entry *) htab_find (ht, &tmp);
1689 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1))
1690 if (INSN_P (XEXP (insn_list, 0)))
1691 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode,
1692 unsignedp, 1, may_share);
1696 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1697 the insn under examination, VAR is the variable to fix up
1698 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1699 TOPLEVEL is nonzero if this is the main insn chain for this
1703 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel, no_share)
1706 enum machine_mode promoted_mode;
1712 rtx set, prev, prev_set;
1715 /* Remember the notes in case we delete the insn. */
1716 note = REG_NOTES (insn);
1718 /* If this is a CLOBBER of VAR, delete it.
1720 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1721 and REG_RETVAL notes too. */
1722 if (GET_CODE (PATTERN (insn)) == CLOBBER
1723 && (XEXP (PATTERN (insn), 0) == var
1724 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1725 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1726 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1728 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1729 /* The REG_LIBCALL note will go away since we are going to
1730 turn INSN into a NOTE, so just delete the
1731 corresponding REG_RETVAL note. */
1732 remove_note (XEXP (note, 0),
1733 find_reg_note (XEXP (note, 0), REG_RETVAL,
1739 /* The insn to load VAR from a home in the arglist
1740 is now a no-op. When we see it, just delete it.
1741 Similarly if this is storing VAR from a register from which
1742 it was loaded in the previous insn. This will occur
1743 when an ADDRESSOF was made for an arglist slot. */
1745 && (set = single_set (insn)) != 0
1746 && SET_DEST (set) == var
1747 /* If this represents the result of an insn group,
1748 don't delete the insn. */
1749 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1750 && (rtx_equal_p (SET_SRC (set), var)
1751 || (GET_CODE (SET_SRC (set)) == REG
1752 && (prev = prev_nonnote_insn (insn)) != 0
1753 && (prev_set = single_set (prev)) != 0
1754 && SET_DEST (prev_set) == SET_SRC (set)
1755 && rtx_equal_p (SET_SRC (prev_set), var))))
1761 struct fixup_replacement *replacements = 0;
1762 rtx next_insn = NEXT_INSN (insn);
1764 if (SMALL_REGISTER_CLASSES)
1766 /* If the insn that copies the results of a CALL_INSN
1767 into a pseudo now references VAR, we have to use an
1768 intermediate pseudo since we want the life of the
1769 return value register to be only a single insn.
1771 If we don't use an intermediate pseudo, such things as
1772 address computations to make the address of VAR valid
1773 if it is not can be placed between the CALL_INSN and INSN.
1775 To make sure this doesn't happen, we record the destination
1776 of the CALL_INSN and see if the next insn uses both that
1779 if (call_dest != 0 && GET_CODE (insn) == INSN
1780 && reg_mentioned_p (var, PATTERN (insn))
1781 && reg_mentioned_p (call_dest, PATTERN (insn)))
1783 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1785 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1787 PATTERN (insn) = replace_rtx (PATTERN (insn),
1791 if (GET_CODE (insn) == CALL_INSN
1792 && GET_CODE (PATTERN (insn)) == SET)
1793 call_dest = SET_DEST (PATTERN (insn));
1794 else if (GET_CODE (insn) == CALL_INSN
1795 && GET_CODE (PATTERN (insn)) == PARALLEL
1796 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1797 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1802 /* See if we have to do anything to INSN now that VAR is in
1803 memory. If it needs to be loaded into a pseudo, use a single
1804 pseudo for the entire insn in case there is a MATCH_DUP
1805 between two operands. We pass a pointer to the head of
1806 a list of struct fixup_replacements. If fixup_var_refs_1
1807 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1808 it will record them in this list.
1810 If it allocated a pseudo for any replacement, we copy into
1813 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1814 &replacements, no_share);
1816 /* If this is last_parm_insn, and any instructions were output
1817 after it to fix it up, then we must set last_parm_insn to
1818 the last such instruction emitted. */
1819 if (insn == last_parm_insn)
1820 last_parm_insn = PREV_INSN (next_insn);
1822 while (replacements)
1824 struct fixup_replacement *next;
1826 if (GET_CODE (replacements->new) == REG)
1831 /* OLD might be a (subreg (mem)). */
1832 if (GET_CODE (replacements->old) == SUBREG)
1834 = fixup_memory_subreg (replacements->old, insn,
1838 = fixup_stack_1 (replacements->old, insn);
1840 insert_before = insn;
1842 /* If we are changing the mode, do a conversion.
1843 This might be wasteful, but combine.c will
1844 eliminate much of the waste. */
1846 if (GET_MODE (replacements->new)
1847 != GET_MODE (replacements->old))
1850 convert_move (replacements->new,
1851 replacements->old, unsignedp);
1856 seq = gen_move_insn (replacements->new,
1859 emit_insn_before (seq, insert_before);
1862 next = replacements->next;
1863 free (replacements);
1864 replacements = next;
1868 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1869 But don't touch other insns referred to by reg-notes;
1870 we will get them elsewhere. */
1873 if (GET_CODE (note) != INSN_LIST)
1875 = walk_fixup_memory_subreg (XEXP (note, 0), insn,
1877 note = XEXP (note, 1);
1881 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1882 See if the rtx expression at *LOC in INSN needs to be changed.
1884 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1885 contain a list of original rtx's and replacements. If we find that we need
1886 to modify this insn by replacing a memory reference with a pseudo or by
1887 making a new MEM to implement a SUBREG, we consult that list to see if
1888 we have already chosen a replacement. If none has already been allocated,
1889 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1890 or the SUBREG, as appropriate, to the pseudo. */
1893 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements, no_share)
1895 enum machine_mode promoted_mode;
1898 struct fixup_replacement **replacements;
1903 RTX_CODE code = GET_CODE (x);
1906 struct fixup_replacement *replacement;
1911 if (XEXP (x, 0) == var)
1913 /* Prevent sharing of rtl that might lose. */
1914 rtx sub = copy_rtx (XEXP (var, 0));
1916 if (! validate_change (insn, loc, sub, 0))
1918 rtx y = gen_reg_rtx (GET_MODE (sub));
1921 /* We should be able to replace with a register or all is lost.
1922 Note that we can't use validate_change to verify this, since
1923 we're not caring for replacing all dups simultaneously. */
1924 if (! validate_replace_rtx (*loc, y, insn))
1927 /* Careful! First try to recognize a direct move of the
1928 value, mimicking how things are done in gen_reload wrt
1929 PLUS. Consider what happens when insn is a conditional
1930 move instruction and addsi3 clobbers flags. */
1933 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1937 if (recog_memoized (new_insn) < 0)
1939 /* That failed. Fall back on force_operand and hope. */
1942 sub = force_operand (sub, y);
1944 emit_insn (gen_move_insn (y, sub));
1950 /* Don't separate setter from user. */
1951 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1952 insn = PREV_INSN (insn);
1955 emit_insn_before (seq, insn);
1963 /* If we already have a replacement, use it. Otherwise,
1964 try to fix up this address in case it is invalid. */
1966 replacement = find_fixup_replacement (replacements, var);
1967 if (replacement->new)
1969 *loc = replacement->new;
1973 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1975 /* Unless we are forcing memory to register or we changed the mode,
1976 we can leave things the way they are if the insn is valid. */
1978 INSN_CODE (insn) = -1;
1979 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1980 && recog_memoized (insn) >= 0)
1983 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1987 /* If X contains VAR, we need to unshare it here so that we update
1988 each occurrence separately. But all identical MEMs in one insn
1989 must be replaced with the same rtx because of the possibility of
1992 if (reg_mentioned_p (var, x))
1994 replacement = find_fixup_replacement (replacements, x);
1995 if (replacement->new == 0)
1996 replacement->new = copy_most_rtx (x, no_share);
1998 *loc = x = replacement->new;
1999 code = GET_CODE (x);
2016 /* Note that in some cases those types of expressions are altered
2017 by optimize_bit_field, and do not survive to get here. */
2018 if (XEXP (x, 0) == var
2019 || (GET_CODE (XEXP (x, 0)) == SUBREG
2020 && SUBREG_REG (XEXP (x, 0)) == var))
2022 /* Get TEM as a valid MEM in the mode presently in the insn.
2024 We don't worry about the possibility of MATCH_DUP here; it
2025 is highly unlikely and would be tricky to handle. */
2028 if (GET_CODE (tem) == SUBREG)
2030 if (GET_MODE_BITSIZE (GET_MODE (tem))
2031 > GET_MODE_BITSIZE (GET_MODE (var)))
2033 replacement = find_fixup_replacement (replacements, var);
2034 if (replacement->new == 0)
2035 replacement->new = gen_reg_rtx (GET_MODE (var));
2036 SUBREG_REG (tem) = replacement->new;
2038 /* The following code works only if we have a MEM, so we
2039 need to handle the subreg here. We directly substitute
2040 it assuming that a subreg must be OK here. We already
2041 scheduled a replacement to copy the mem into the
2047 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2050 tem = fixup_stack_1 (tem, insn);
2052 /* Unless we want to load from memory, get TEM into the proper mode
2053 for an extract from memory. This can only be done if the
2054 extract is at a constant position and length. */
2056 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2057 && GET_CODE (XEXP (x, 2)) == CONST_INT
2058 && ! mode_dependent_address_p (XEXP (tem, 0))
2059 && ! MEM_VOLATILE_P (tem))
2061 enum machine_mode wanted_mode = VOIDmode;
2062 enum machine_mode is_mode = GET_MODE (tem);
2063 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2065 if (GET_CODE (x) == ZERO_EXTRACT)
2067 enum machine_mode new_mode
2068 = mode_for_extraction (EP_extzv, 1);
2069 if (new_mode != MAX_MACHINE_MODE)
2070 wanted_mode = new_mode;
2072 else if (GET_CODE (x) == SIGN_EXTRACT)
2074 enum machine_mode new_mode
2075 = mode_for_extraction (EP_extv, 1);
2076 if (new_mode != MAX_MACHINE_MODE)
2077 wanted_mode = new_mode;
2080 /* If we have a narrower mode, we can do something. */
2081 if (wanted_mode != VOIDmode
2082 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2084 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2085 rtx old_pos = XEXP (x, 2);
2088 /* If the bytes and bits are counted differently, we
2089 must adjust the offset. */
2090 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2091 offset = (GET_MODE_SIZE (is_mode)
2092 - GET_MODE_SIZE (wanted_mode) - offset);
2094 pos %= GET_MODE_BITSIZE (wanted_mode);
2096 newmem = adjust_address_nv (tem, wanted_mode, offset);
2098 /* Make the change and see if the insn remains valid. */
2099 INSN_CODE (insn) = -1;
2100 XEXP (x, 0) = newmem;
2101 XEXP (x, 2) = GEN_INT (pos);
2103 if (recog_memoized (insn) >= 0)
2106 /* Otherwise, restore old position. XEXP (x, 0) will be
2108 XEXP (x, 2) = old_pos;
2112 /* If we get here, the bitfield extract insn can't accept a memory
2113 reference. Copy the input into a register. */
2115 tem1 = gen_reg_rtx (GET_MODE (tem));
2116 emit_insn_before (gen_move_insn (tem1, tem), insn);
2123 if (SUBREG_REG (x) == var)
2125 /* If this is a special SUBREG made because VAR was promoted
2126 from a wider mode, replace it with VAR and call ourself
2127 recursively, this time saying that the object previously
2128 had its current mode (by virtue of the SUBREG). */
2130 if (SUBREG_PROMOTED_VAR_P (x))
2133 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements,
2138 /* If this SUBREG makes VAR wider, it has become a paradoxical
2139 SUBREG with VAR in memory, but these aren't allowed at this
2140 stage of the compilation. So load VAR into a pseudo and take
2141 a SUBREG of that pseudo. */
2142 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2144 replacement = find_fixup_replacement (replacements, var);
2145 if (replacement->new == 0)
2146 replacement->new = gen_reg_rtx (promoted_mode);
2147 SUBREG_REG (x) = replacement->new;
2151 /* See if we have already found a replacement for this SUBREG.
2152 If so, use it. Otherwise, make a MEM and see if the insn
2153 is recognized. If not, or if we should force MEM into a register,
2154 make a pseudo for this SUBREG. */
2155 replacement = find_fixup_replacement (replacements, x);
2156 if (replacement->new)
2158 *loc = replacement->new;
2162 replacement->new = *loc = fixup_memory_subreg (x, insn,
2165 INSN_CODE (insn) = -1;
2166 if (! flag_force_mem && recog_memoized (insn) >= 0)
2169 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2175 /* First do special simplification of bit-field references. */
2176 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2177 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2178 optimize_bit_field (x, insn, 0);
2179 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2180 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2181 optimize_bit_field (x, insn, 0);
2183 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2184 into a register and then store it back out. */
2185 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2186 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2187 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2188 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2189 > GET_MODE_SIZE (GET_MODE (var))))
2191 replacement = find_fixup_replacement (replacements, var);
2192 if (replacement->new == 0)
2193 replacement->new = gen_reg_rtx (GET_MODE (var));
2195 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2196 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2199 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2200 insn into a pseudo and store the low part of the pseudo into VAR. */
2201 if (GET_CODE (SET_DEST (x)) == SUBREG
2202 && SUBREG_REG (SET_DEST (x)) == var
2203 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2204 > GET_MODE_SIZE (GET_MODE (var))))
2206 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2207 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2214 rtx dest = SET_DEST (x);
2215 rtx src = SET_SRC (x);
2216 rtx outerdest = dest;
2218 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2219 || GET_CODE (dest) == SIGN_EXTRACT
2220 || GET_CODE (dest) == ZERO_EXTRACT)
2221 dest = XEXP (dest, 0);
2223 if (GET_CODE (src) == SUBREG)
2224 src = SUBREG_REG (src);
2226 /* If VAR does not appear at the top level of the SET
2227 just scan the lower levels of the tree. */
2229 if (src != var && dest != var)
2232 /* We will need to rerecognize this insn. */
2233 INSN_CODE (insn) = -1;
2235 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var
2236 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE)
2238 /* Since this case will return, ensure we fixup all the
2240 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2241 insn, replacements, no_share);
2242 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2243 insn, replacements, no_share);
2244 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2245 insn, replacements, no_share);
2247 tem = XEXP (outerdest, 0);
2249 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2250 that may appear inside a ZERO_EXTRACT.
2251 This was legitimate when the MEM was a REG. */
2252 if (GET_CODE (tem) == SUBREG
2253 && SUBREG_REG (tem) == var)
2254 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2256 tem = fixup_stack_1 (tem, insn);
2258 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2259 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2260 && ! mode_dependent_address_p (XEXP (tem, 0))
2261 && ! MEM_VOLATILE_P (tem))
2263 enum machine_mode wanted_mode;
2264 enum machine_mode is_mode = GET_MODE (tem);
2265 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2267 wanted_mode = mode_for_extraction (EP_insv, 0);
2269 /* If we have a narrower mode, we can do something. */
2270 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2272 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2273 rtx old_pos = XEXP (outerdest, 2);
2276 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2277 offset = (GET_MODE_SIZE (is_mode)
2278 - GET_MODE_SIZE (wanted_mode) - offset);
2280 pos %= GET_MODE_BITSIZE (wanted_mode);
2282 newmem = adjust_address_nv (tem, wanted_mode, offset);
2284 /* Make the change and see if the insn remains valid. */
2285 INSN_CODE (insn) = -1;
2286 XEXP (outerdest, 0) = newmem;
2287 XEXP (outerdest, 2) = GEN_INT (pos);
2289 if (recog_memoized (insn) >= 0)
2292 /* Otherwise, restore old position. XEXP (x, 0) will be
2294 XEXP (outerdest, 2) = old_pos;
2298 /* If we get here, the bit-field store doesn't allow memory
2299 or isn't located at a constant position. Load the value into
2300 a register, do the store, and put it back into memory. */
2302 tem1 = gen_reg_rtx (GET_MODE (tem));
2303 emit_insn_before (gen_move_insn (tem1, tem), insn);
2304 emit_insn_after (gen_move_insn (tem, tem1), insn);
2305 XEXP (outerdest, 0) = tem1;
2309 /* STRICT_LOW_PART is a no-op on memory references
2310 and it can cause combinations to be unrecognizable,
2313 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2314 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2316 /* A valid insn to copy VAR into or out of a register
2317 must be left alone, to avoid an infinite loop here.
2318 If the reference to VAR is by a subreg, fix that up,
2319 since SUBREG is not valid for a memref.
2320 Also fix up the address of the stack slot.
2322 Note that we must not try to recognize the insn until
2323 after we know that we have valid addresses and no
2324 (subreg (mem ...) ...) constructs, since these interfere
2325 with determining the validity of the insn. */
2327 if ((SET_SRC (x) == var
2328 || (GET_CODE (SET_SRC (x)) == SUBREG
2329 && SUBREG_REG (SET_SRC (x)) == var))
2330 && (GET_CODE (SET_DEST (x)) == REG
2331 || (GET_CODE (SET_DEST (x)) == SUBREG
2332 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2333 && GET_MODE (var) == promoted_mode
2334 && x == single_set (insn))
2338 if (GET_CODE (SET_SRC (x)) == SUBREG
2339 && (GET_MODE_SIZE (GET_MODE (SET_SRC (x)))
2340 > GET_MODE_SIZE (GET_MODE (var))))
2342 /* This (subreg VAR) is now a paradoxical subreg. We need
2343 to replace VAR instead of the subreg. */
2344 replacement = find_fixup_replacement (replacements, var);
2345 if (replacement->new == NULL_RTX)
2346 replacement->new = gen_reg_rtx (GET_MODE (var));
2347 SUBREG_REG (SET_SRC (x)) = replacement->new;
2351 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2352 if (replacement->new)
2353 SET_SRC (x) = replacement->new;
2354 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2355 SET_SRC (x) = replacement->new
2356 = fixup_memory_subreg (SET_SRC (x), insn, promoted_mode,
2359 SET_SRC (x) = replacement->new
2360 = fixup_stack_1 (SET_SRC (x), insn);
2363 if (recog_memoized (insn) >= 0)
2366 /* INSN is not valid, but we know that we want to
2367 copy SET_SRC (x) to SET_DEST (x) in some way. So
2368 we generate the move and see whether it requires more
2369 than one insn. If it does, we emit those insns and
2370 delete INSN. Otherwise, we can just replace the pattern
2371 of INSN; we have already verified above that INSN has
2372 no other function that to do X. */
2374 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2375 if (NEXT_INSN (pat) != NULL_RTX)
2377 last = emit_insn_before (pat, insn);
2379 /* INSN might have REG_RETVAL or other important notes, so
2380 we need to store the pattern of the last insn in the
2381 sequence into INSN similarly to the normal case. LAST
2382 should not have REG_NOTES, but we allow them if INSN has
2384 if (REG_NOTES (last) && REG_NOTES (insn))
2386 if (REG_NOTES (last))
2387 REG_NOTES (insn) = REG_NOTES (last);
2388 PATTERN (insn) = PATTERN (last);
2393 PATTERN (insn) = PATTERN (pat);
2398 if ((SET_DEST (x) == var
2399 || (GET_CODE (SET_DEST (x)) == SUBREG
2400 && SUBREG_REG (SET_DEST (x)) == var))
2401 && (GET_CODE (SET_SRC (x)) == REG
2402 || (GET_CODE (SET_SRC (x)) == SUBREG
2403 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2404 && GET_MODE (var) == promoted_mode
2405 && x == single_set (insn))
2409 if (GET_CODE (SET_DEST (x)) == SUBREG)
2410 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn,
2413 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2415 if (recog_memoized (insn) >= 0)
2418 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2419 if (NEXT_INSN (pat) != NULL_RTX)
2421 last = emit_insn_before (pat, insn);
2423 /* INSN might have REG_RETVAL or other important notes, so
2424 we need to store the pattern of the last insn in the
2425 sequence into INSN similarly to the normal case. LAST
2426 should not have REG_NOTES, but we allow them if INSN has
2428 if (REG_NOTES (last) && REG_NOTES (insn))
2430 if (REG_NOTES (last))
2431 REG_NOTES (insn) = REG_NOTES (last);
2432 PATTERN (insn) = PATTERN (last);
2437 PATTERN (insn) = PATTERN (pat);
2442 /* Otherwise, storing into VAR must be handled specially
2443 by storing into a temporary and copying that into VAR
2444 with a new insn after this one. Note that this case
2445 will be used when storing into a promoted scalar since
2446 the insn will now have different modes on the input
2447 and output and hence will be invalid (except for the case
2448 of setting it to a constant, which does not need any
2449 change if it is valid). We generate extra code in that case,
2450 but combine.c will eliminate it. */
2455 rtx fixeddest = SET_DEST (x);
2456 enum machine_mode temp_mode;
2458 /* STRICT_LOW_PART can be discarded, around a MEM. */
2459 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2460 fixeddest = XEXP (fixeddest, 0);
2461 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2462 if (GET_CODE (fixeddest) == SUBREG)
2464 fixeddest = fixup_memory_subreg (fixeddest, insn,
2466 temp_mode = GET_MODE (fixeddest);
2470 fixeddest = fixup_stack_1 (fixeddest, insn);
2471 temp_mode = promoted_mode;
2474 temp = gen_reg_rtx (temp_mode);
2476 emit_insn_after (gen_move_insn (fixeddest,
2477 gen_lowpart (GET_MODE (fixeddest),
2481 SET_DEST (x) = temp;
2489 /* Nothing special about this RTX; fix its operands. */
2491 fmt = GET_RTX_FORMAT (code);
2492 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2495 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements,
2497 else if (fmt[i] == 'E')
2500 for (j = 0; j < XVECLEN (x, i); j++)
2501 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2502 insn, replacements, no_share);
2507 /* Previously, X had the form (SUBREG:m1 (REG:PROMOTED_MODE ...)).
2508 The REG was placed on the stack, so X now has the form (SUBREG:m1
2511 Return an rtx (MEM:m1 newaddr) which is equivalent. If any insns
2512 must be emitted to compute NEWADDR, put them before INSN.
2514 UNCRITICAL nonzero means accept paradoxical subregs.
2515 This is used for subregs found inside REG_NOTES. */
2518 fixup_memory_subreg (x, insn, promoted_mode, uncritical)
2521 enum machine_mode promoted_mode;
2525 rtx mem = SUBREG_REG (x);
2526 rtx addr = XEXP (mem, 0);
2527 enum machine_mode mode = GET_MODE (x);
2530 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2531 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (mem)) && ! uncritical)
2534 offset = SUBREG_BYTE (x);
2535 if (BYTES_BIG_ENDIAN)
2536 /* If the PROMOTED_MODE is wider than the mode of the MEM, adjust
2537 the offset so that it points to the right location within the
2539 offset -= (GET_MODE_SIZE (promoted_mode) - GET_MODE_SIZE (GET_MODE (mem)));
2541 if (!flag_force_addr
2542 && memory_address_p (mode, plus_constant (addr, offset)))
2543 /* Shortcut if no insns need be emitted. */
2544 return adjust_address (mem, mode, offset);
2547 result = adjust_address (mem, mode, offset);
2551 emit_insn_before (seq, insn);
2555 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2556 Replace subexpressions of X in place.
2557 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2558 Otherwise return X, with its contents possibly altered.
2560 INSN, PROMOTED_MODE and UNCRITICAL are as for
2561 fixup_memory_subreg. */
2564 walk_fixup_memory_subreg (x, insn, promoted_mode, uncritical)
2567 enum machine_mode promoted_mode;
2577 code = GET_CODE (x);
2579 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2580 return fixup_memory_subreg (x, insn, promoted_mode, uncritical);
2582 /* Nothing special about this RTX; fix its operands. */
2584 fmt = GET_RTX_FORMAT (code);
2585 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2588 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn,
2589 promoted_mode, uncritical);
2590 else if (fmt[i] == 'E')
2593 for (j = 0; j < XVECLEN (x, i); j++)
2595 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn,
2596 promoted_mode, uncritical);
2602 /* For each memory ref within X, if it refers to a stack slot
2603 with an out of range displacement, put the address in a temp register
2604 (emitting new insns before INSN to load these registers)
2605 and alter the memory ref to use that register.
2606 Replace each such MEM rtx with a copy, to avoid clobberage. */
2609 fixup_stack_1 (x, insn)
2614 RTX_CODE code = GET_CODE (x);
2619 rtx ad = XEXP (x, 0);
2620 /* If we have address of a stack slot but it's not valid
2621 (displacement is too large), compute the sum in a register. */
2622 if (GET_CODE (ad) == PLUS
2623 && GET_CODE (XEXP (ad, 0)) == REG
2624 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2625 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2626 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2627 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2628 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2630 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2631 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2632 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2633 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2636 if (memory_address_p (GET_MODE (x), ad))
2640 temp = copy_to_reg (ad);
2643 emit_insn_before (seq, insn);
2644 return replace_equiv_address (x, temp);
2649 fmt = GET_RTX_FORMAT (code);
2650 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2653 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2654 else if (fmt[i] == 'E')
2657 for (j = 0; j < XVECLEN (x, i); j++)
2658 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2664 /* Optimization: a bit-field instruction whose field
2665 happens to be a byte or halfword in memory
2666 can be changed to a move instruction.
2668 We call here when INSN is an insn to examine or store into a bit-field.
2669 BODY is the SET-rtx to be altered.
2671 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2672 (Currently this is called only from function.c, and EQUIV_MEM
2676 optimize_bit_field (body, insn, equiv_mem)
2684 enum machine_mode mode;
2686 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2687 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2688 bitfield = SET_DEST (body), destflag = 1;
2690 bitfield = SET_SRC (body), destflag = 0;
2692 /* First check that the field being stored has constant size and position
2693 and is in fact a byte or halfword suitably aligned. */
2695 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2696 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2697 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2699 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2703 /* Now check that the containing word is memory, not a register,
2704 and that it is safe to change the machine mode. */
2706 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2707 memref = XEXP (bitfield, 0);
2708 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2710 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2711 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2712 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2713 memref = SUBREG_REG (XEXP (bitfield, 0));
2714 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2716 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2717 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2720 && ! mode_dependent_address_p (XEXP (memref, 0))
2721 && ! MEM_VOLATILE_P (memref))
2723 /* Now adjust the address, first for any subreg'ing
2724 that we are now getting rid of,
2725 and then for which byte of the word is wanted. */
2727 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2730 /* Adjust OFFSET to count bits from low-address byte. */
2731 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2732 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2733 - offset - INTVAL (XEXP (bitfield, 1)));
2735 /* Adjust OFFSET to count bytes from low-address byte. */
2736 offset /= BITS_PER_UNIT;
2737 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2739 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2740 / UNITS_PER_WORD) * UNITS_PER_WORD;
2741 if (BYTES_BIG_ENDIAN)
2742 offset -= (MIN (UNITS_PER_WORD,
2743 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2744 - MIN (UNITS_PER_WORD,
2745 GET_MODE_SIZE (GET_MODE (memref))));
2749 memref = adjust_address (memref, mode, offset);
2750 insns = get_insns ();
2752 emit_insn_before (insns, insn);
2754 /* Store this memory reference where
2755 we found the bit field reference. */
2759 validate_change (insn, &SET_DEST (body), memref, 1);
2760 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2762 rtx src = SET_SRC (body);
2763 while (GET_CODE (src) == SUBREG
2764 && SUBREG_BYTE (src) == 0)
2765 src = SUBREG_REG (src);
2766 if (GET_MODE (src) != GET_MODE (memref))
2767 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2768 validate_change (insn, &SET_SRC (body), src, 1);
2770 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2771 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2772 /* This shouldn't happen because anything that didn't have
2773 one of these modes should have got converted explicitly
2774 and then referenced through a subreg.
2775 This is so because the original bit-field was
2776 handled by agg_mode and so its tree structure had
2777 the same mode that memref now has. */
2782 rtx dest = SET_DEST (body);
2784 while (GET_CODE (dest) == SUBREG
2785 && SUBREG_BYTE (dest) == 0
2786 && (GET_MODE_CLASS (GET_MODE (dest))
2787 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2788 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2790 dest = SUBREG_REG (dest);
2792 validate_change (insn, &SET_DEST (body), dest, 1);
2794 if (GET_MODE (dest) == GET_MODE (memref))
2795 validate_change (insn, &SET_SRC (body), memref, 1);
2798 /* Convert the mem ref to the destination mode. */
2799 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2802 convert_move (newreg, memref,
2803 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2807 validate_change (insn, &SET_SRC (body), newreg, 1);
2811 /* See if we can convert this extraction or insertion into
2812 a simple move insn. We might not be able to do so if this
2813 was, for example, part of a PARALLEL.
2815 If we succeed, write out any needed conversions. If we fail,
2816 it is hard to guess why we failed, so don't do anything
2817 special; just let the optimization be suppressed. */
2819 if (apply_change_group () && seq)
2820 emit_insn_before (seq, insn);
2825 /* These routines are responsible for converting virtual register references
2826 to the actual hard register references once RTL generation is complete.
2828 The following four variables are used for communication between the
2829 routines. They contain the offsets of the virtual registers from their
2830 respective hard registers. */
2832 static int in_arg_offset;
2833 static int var_offset;
2834 static int dynamic_offset;
2835 static int out_arg_offset;
2836 static int cfa_offset;
2838 /* In most machines, the stack pointer register is equivalent to the bottom
2841 #ifndef STACK_POINTER_OFFSET
2842 #define STACK_POINTER_OFFSET 0
2845 /* If not defined, pick an appropriate default for the offset of dynamically
2846 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2847 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2849 #ifndef STACK_DYNAMIC_OFFSET
2851 /* The bottom of the stack points to the actual arguments. If
2852 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2853 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2854 stack space for register parameters is not pushed by the caller, but
2855 rather part of the fixed stack areas and hence not included in
2856 `current_function_outgoing_args_size'. Nevertheless, we must allow
2857 for it when allocating stack dynamic objects. */
2859 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2860 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2861 ((ACCUMULATE_OUTGOING_ARGS \
2862 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2863 + (STACK_POINTER_OFFSET)) \
2866 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2867 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2868 + (STACK_POINTER_OFFSET))
2872 /* On most machines, the CFA coincides with the first incoming parm. */
2874 #ifndef ARG_POINTER_CFA_OFFSET
2875 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2878 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just
2879 had its address taken. DECL is the decl or SAVE_EXPR for the
2880 object stored in the register, for later use if we do need to force
2881 REG into the stack. REG is overwritten by the MEM like in
2882 put_reg_into_stack. RESCAN is true if previously emitted
2883 instructions must be rescanned and modified now that the REG has
2884 been transformed. */
2887 gen_mem_addressof (reg, decl, rescan)
2892 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2895 /* Calculate this before we start messing with decl's RTL. */
2896 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0;
2898 /* If the original REG was a user-variable, then so is the REG whose
2899 address is being taken. Likewise for unchanging. */
2900 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2901 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2903 PUT_CODE (reg, MEM);
2904 MEM_ATTRS (reg) = 0;
2909 tree type = TREE_TYPE (decl);
2910 enum machine_mode decl_mode
2911 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl)));
2912 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl)
2913 : DECL_RTL_IF_SET (decl));
2915 PUT_MODE (reg, decl_mode);
2917 /* Clear DECL_RTL momentarily so functions below will work
2918 properly, then set it again. */
2919 if (DECL_P (decl) && decl_rtl == reg)
2920 SET_DECL_RTL (decl, 0);
2922 set_mem_attributes (reg, decl, 1);
2923 set_mem_alias_set (reg, set);
2925 if (DECL_P (decl) && decl_rtl == reg)
2926 SET_DECL_RTL (decl, reg);
2929 && (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0)))
2930 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), reg, 0);
2933 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0);
2938 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2941 flush_addressof (decl)
2944 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2945 && DECL_RTL (decl) != 0
2946 && GET_CODE (DECL_RTL (decl)) == MEM
2947 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2948 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2949 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2952 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2955 put_addressof_into_stack (r, ht)
2960 int volatile_p, used_p;
2962 rtx reg = XEXP (r, 0);
2964 if (GET_CODE (reg) != REG)
2967 decl = ADDRESSOF_DECL (r);
2970 type = TREE_TYPE (decl);
2971 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2972 && TREE_THIS_VOLATILE (decl));
2973 used_p = (TREE_USED (decl)
2974 || (DECL_P (decl) && DECL_INITIAL (decl) != 0));
2983 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2984 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2987 /* List of replacements made below in purge_addressof_1 when creating
2988 bitfield insertions. */
2989 static rtx purge_bitfield_addressof_replacements;
2991 /* List of replacements made below in purge_addressof_1 for patterns
2992 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2993 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2994 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2995 enough in complex cases, e.g. when some field values can be
2996 extracted by usage MEM with narrower mode. */
2997 static rtx purge_addressof_replacements;
2999 /* Helper function for purge_addressof. See if the rtx expression at *LOC
3000 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
3001 the stack. If the function returns FALSE then the replacement could not
3005 purge_addressof_1 (loc, insn, force, store, ht)
3017 /* Re-start here to avoid recursion in common cases. */
3024 code = GET_CODE (x);
3026 /* If we don't return in any of the cases below, we will recurse inside
3027 the RTX, which will normally result in any ADDRESSOF being forced into
3031 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
3032 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
3035 else if (code == ADDRESSOF)
3039 if (GET_CODE (XEXP (x, 0)) != MEM)
3040 put_addressof_into_stack (x, ht);
3042 /* We must create a copy of the rtx because it was created by
3043 overwriting a REG rtx which is always shared. */
3044 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
3045 if (validate_change (insn, loc, sub, 0)
3046 || validate_replace_rtx (x, sub, insn))
3050 sub = force_operand (sub, NULL_RTX);
3051 if (! validate_change (insn, loc, sub, 0)
3052 && ! validate_replace_rtx (x, sub, insn))
3055 insns = get_insns ();
3057 emit_insn_before (insns, insn);
3061 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3063 rtx sub = XEXP (XEXP (x, 0), 0);
3065 if (GET_CODE (sub) == MEM)
3066 sub = adjust_address_nv (sub, GET_MODE (x), 0);
3067 else if (GET_CODE (sub) == REG
3068 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3070 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3072 int size_x, size_sub;
3076 /* When processing REG_NOTES look at the list of
3077 replacements done on the insn to find the register that X
3081 for (tem = purge_bitfield_addressof_replacements;
3083 tem = XEXP (XEXP (tem, 1), 1))
3084 if (rtx_equal_p (x, XEXP (tem, 0)))
3086 *loc = XEXP (XEXP (tem, 1), 0);
3090 /* See comment for purge_addressof_replacements. */
3091 for (tem = purge_addressof_replacements;
3093 tem = XEXP (XEXP (tem, 1), 1))
3094 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3096 rtx z = XEXP (XEXP (tem, 1), 0);
3098 if (GET_MODE (x) == GET_MODE (z)
3099 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3100 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3103 /* It can happen that the note may speak of things
3104 in a wider (or just different) mode than the
3105 code did. This is especially true of
3108 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3111 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3112 && (GET_MODE_SIZE (GET_MODE (x))
3113 > GET_MODE_SIZE (GET_MODE (z))))
3115 /* This can occur as a result in invalid
3116 pointer casts, e.g. float f; ...
3117 *(long long int *)&f.
3118 ??? We could emit a warning here, but
3119 without a line number that wouldn't be
3121 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3124 z = gen_lowpart (GET_MODE (x), z);
3130 /* Sometimes we may not be able to find the replacement. For
3131 example when the original insn was a MEM in a wider mode,
3132 and the note is part of a sign extension of a narrowed
3133 version of that MEM. Gcc testcase compile/990829-1.c can
3134 generate an example of this situation. Rather than complain
3135 we return false, which will prompt our caller to remove the
3140 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3141 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3143 /* Do not frob unchanging MEMs. If a later reference forces the
3144 pseudo to the stack, we can wind up with multiple writes to
3145 an unchanging memory, which is invalid. */
3146 if (RTX_UNCHANGING_P (x) && size_x != size_sub)
3149 /* Don't even consider working with paradoxical subregs,
3150 or the moral equivalent seen here. */
3151 else if (size_x <= size_sub
3152 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3154 /* Do a bitfield insertion to mirror what would happen
3161 rtx p = PREV_INSN (insn);
3164 val = gen_reg_rtx (GET_MODE (x));
3165 if (! validate_change (insn, loc, val, 0))
3167 /* Discard the current sequence and put the
3168 ADDRESSOF on stack. */
3174 emit_insn_before (seq, insn);
3175 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3179 store_bit_field (sub, size_x, 0, GET_MODE (x),
3180 val, GET_MODE_SIZE (GET_MODE (sub)));
3182 /* Make sure to unshare any shared rtl that store_bit_field
3183 might have created. */
3184 unshare_all_rtl_again (get_insns ());
3188 p = emit_insn_after (seq, insn);
3189 if (NEXT_INSN (insn))
3190 compute_insns_for_mem (NEXT_INSN (insn),
3191 p ? NEXT_INSN (p) : NULL_RTX,
3196 rtx p = PREV_INSN (insn);
3199 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3200 GET_MODE (x), GET_MODE (x),
3201 GET_MODE_SIZE (GET_MODE (sub)));
3203 if (! validate_change (insn, loc, val, 0))
3205 /* Discard the current sequence and put the
3206 ADDRESSOF on stack. */
3213 emit_insn_before (seq, insn);
3214 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3218 /* Remember the replacement so that the same one can be done
3219 on the REG_NOTES. */
3220 purge_bitfield_addressof_replacements
3221 = gen_rtx_EXPR_LIST (VOIDmode, x,
3224 purge_bitfield_addressof_replacements));
3226 /* We replaced with a reg -- all done. */
3231 else if (validate_change (insn, loc, sub, 0))
3233 /* Remember the replacement so that the same one can be done
3234 on the REG_NOTES. */
3235 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3239 for (tem = purge_addressof_replacements;
3241 tem = XEXP (XEXP (tem, 1), 1))
3242 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3244 XEXP (XEXP (tem, 1), 0) = sub;
3247 purge_addressof_replacements
3248 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3249 gen_rtx_EXPR_LIST (VOIDmode, sub,
3250 purge_addressof_replacements));
3258 /* Scan all subexpressions. */
3259 fmt = GET_RTX_FORMAT (code);
3260 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3263 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0, ht);
3264 else if (*fmt == 'E')
3265 for (j = 0; j < XVECLEN (x, i); j++)
3266 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, ht);
3272 /* Return a hash value for K, a REG. */
3275 insns_for_mem_hash (k)
3278 /* Use the address of the key for the hash value. */
3279 struct insns_for_mem_entry *m = (struct insns_for_mem_entry *) k;
3280 return htab_hash_pointer (m->key);
3283 /* Return nonzero if K1 and K2 (two REGs) are the same. */
3286 insns_for_mem_comp (k1, k2)
3290 struct insns_for_mem_entry *m1 = (struct insns_for_mem_entry *) k1;
3291 struct insns_for_mem_entry *m2 = (struct insns_for_mem_entry *) k2;
3292 return m1->key == m2->key;
3295 struct insns_for_mem_walk_info
3297 /* The hash table that we are using to record which INSNs use which
3301 /* The INSN we are currently processing. */
3304 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3305 to find the insns that use the REGs in the ADDRESSOFs. */
3309 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3310 that might be used in an ADDRESSOF expression, record this INSN in
3311 the hash table given by DATA (which is really a pointer to an
3312 insns_for_mem_walk_info structure). */
3315 insns_for_mem_walk (r, data)
3319 struct insns_for_mem_walk_info *ifmwi
3320 = (struct insns_for_mem_walk_info *) data;
3321 struct insns_for_mem_entry tmp;
3322 tmp.insns = NULL_RTX;
3324 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3325 && GET_CODE (XEXP (*r, 0)) == REG)
3328 tmp.key = XEXP (*r, 0);
3329 e = htab_find_slot (ifmwi->ht, &tmp, INSERT);
3332 *e = ggc_alloc (sizeof (tmp));
3333 memcpy (*e, &tmp, sizeof (tmp));
3336 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3338 struct insns_for_mem_entry *ifme;
3340 ifme = (struct insns_for_mem_entry *) htab_find (ifmwi->ht, &tmp);
3342 /* If we have not already recorded this INSN, do so now. Since
3343 we process the INSNs in order, we know that if we have
3344 recorded it it must be at the front of the list. */
3345 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3346 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3353 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3354 which REGs in HT. */
3357 compute_insns_for_mem (insns, last_insn, ht)
3363 struct insns_for_mem_walk_info ifmwi;
3366 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3367 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3371 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3375 /* Helper function for purge_addressof called through for_each_rtx.
3376 Returns true iff the rtl is an ADDRESSOF. */
3379 is_addressof (rtl, data)
3381 void *data ATTRIBUTE_UNUSED;
3383 return GET_CODE (*rtl) == ADDRESSOF;
3386 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3387 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3391 purge_addressof (insns)
3397 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3398 requires a fixup pass over the instruction stream to correct
3399 INSNs that depended on the REG being a REG, and not a MEM. But,
3400 these fixup passes are slow. Furthermore, most MEMs are not
3401 mentioned in very many instructions. So, we speed up the process
3402 by pre-calculating which REGs occur in which INSNs; that allows
3403 us to perform the fixup passes much more quickly. */
3404 ht = htab_create_ggc (1000, insns_for_mem_hash, insns_for_mem_comp, NULL);
3405 compute_insns_for_mem (insns, NULL_RTX, ht);
3407 for (insn = insns; insn; insn = NEXT_INSN (insn))
3410 if (! purge_addressof_1 (&PATTERN (insn), insn,
3411 asm_noperands (PATTERN (insn)) > 0, 0, ht))
3412 /* If we could not replace the ADDRESSOFs in the insn,
3413 something is wrong. */
3416 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, ht))
3418 /* If we could not replace the ADDRESSOFs in the insn's notes,
3419 we can just remove the offending notes instead. */
3422 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3424 /* If we find a REG_RETVAL note then the insn is a libcall.
3425 Such insns must have REG_EQUAL notes as well, in order
3426 for later passes of the compiler to work. So it is not
3427 safe to delete the notes here, and instead we abort. */
3428 if (REG_NOTE_KIND (note) == REG_RETVAL)
3430 if (for_each_rtx (¬e, is_addressof, NULL))
3431 remove_note (insn, note);
3437 purge_bitfield_addressof_replacements = 0;
3438 purge_addressof_replacements = 0;
3440 /* REGs are shared. purge_addressof will destructively replace a REG
3441 with a MEM, which creates shared MEMs.
3443 Unfortunately, the children of put_reg_into_stack assume that MEMs
3444 referring to the same stack slot are shared (fixup_var_refs and
3445 the associated hash table code).
3447 So, we have to do another unsharing pass after we have flushed any
3448 REGs that had their address taken into the stack.
3450 It may be worth tracking whether or not we converted any REGs into
3451 MEMs to avoid this overhead when it is not needed. */
3452 unshare_all_rtl_again (get_insns ());
3455 /* Convert a SET of a hard subreg to a set of the appropriate hard
3456 register. A subroutine of purge_hard_subreg_sets. */
3459 purge_single_hard_subreg_set (pattern)
3462 rtx reg = SET_DEST (pattern);
3463 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3466 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3467 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3469 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3470 GET_MODE (SUBREG_REG (reg)),
3473 reg = SUBREG_REG (reg);
3477 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3479 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3480 SET_DEST (pattern) = reg;
3484 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3485 only such SETs that we expect to see are those left in because
3486 integrate can't handle sets of parts of a return value register.
3488 We don't use alter_subreg because we only want to eliminate subregs
3489 of hard registers. */
3492 purge_hard_subreg_sets (insn)
3495 for (; insn; insn = NEXT_INSN (insn))
3499 rtx pattern = PATTERN (insn);
3500 switch (GET_CODE (pattern))
3503 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3504 purge_single_hard_subreg_set (pattern);
3509 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3511 rtx inner_pattern = XVECEXP (pattern, 0, j);
3512 if (GET_CODE (inner_pattern) == SET
3513 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3514 purge_single_hard_subreg_set (inner_pattern);
3525 /* Pass through the INSNS of function FNDECL and convert virtual register
3526 references to hard register references. */
3529 instantiate_virtual_regs (fndecl, insns)
3536 /* Compute the offsets to use for this function. */
3537 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3538 var_offset = STARTING_FRAME_OFFSET;
3539 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3540 out_arg_offset = STACK_POINTER_OFFSET;
3541 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3543 /* Scan all variables and parameters of this function. For each that is
3544 in memory, instantiate all virtual registers if the result is a valid
3545 address. If not, we do it later. That will handle most uses of virtual
3546 regs on many machines. */
3547 instantiate_decls (fndecl, 1);
3549 /* Initialize recognition, indicating that volatile is OK. */
3552 /* Scan through all the insns, instantiating every virtual register still
3554 for (insn = insns; insn; insn = NEXT_INSN (insn))
3555 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3556 || GET_CODE (insn) == CALL_INSN)
3558 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3559 if (INSN_DELETED_P (insn))
3561 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3562 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3563 if (GET_CODE (insn) == CALL_INSN)
3564 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3568 /* Instantiate the stack slots for the parm registers, for later use in
3569 addressof elimination. */
3570 for (i = 0; i < max_parm_reg; ++i)
3571 if (parm_reg_stack_loc[i])
3572 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3574 /* Now instantiate the remaining register equivalences for debugging info.
3575 These will not be valid addresses. */
3576 instantiate_decls (fndecl, 0);
3578 /* Indicate that, from now on, assign_stack_local should use
3579 frame_pointer_rtx. */
3580 virtuals_instantiated = 1;
3583 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3584 all virtual registers in their DECL_RTL's.
3586 If VALID_ONLY, do this only if the resulting address is still valid.
3587 Otherwise, always do it. */
3590 instantiate_decls (fndecl, valid_only)
3596 /* Process all parameters of the function. */
3597 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3599 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3600 HOST_WIDE_INT size_rtl;
3602 instantiate_decl (DECL_RTL (decl), size, valid_only);
3604 /* If the parameter was promoted, then the incoming RTL mode may be
3605 larger than the declared type size. We must use the larger of
3607 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3608 size = MAX (size_rtl, size);
3609 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3612 /* Now process all variables defined in the function or its subblocks. */
3613 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3616 /* Subroutine of instantiate_decls: Process all decls in the given
3617 BLOCK node and all its subblocks. */
3620 instantiate_decls_1 (let, valid_only)
3626 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3627 if (DECL_RTL_SET_P (t))
3628 instantiate_decl (DECL_RTL (t),
3629 int_size_in_bytes (TREE_TYPE (t)),
3632 /* Process all subblocks. */
3633 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3634 instantiate_decls_1 (t, valid_only);
3637 /* Subroutine of the preceding procedures: Given RTL representing a
3638 decl and the size of the object, do any instantiation required.
3640 If VALID_ONLY is nonzero, it means that the RTL should only be
3641 changed if the new address is valid. */
3644 instantiate_decl (x, size, valid_only)
3649 enum machine_mode mode;
3652 /* If this is not a MEM, no need to do anything. Similarly if the
3653 address is a constant or a register that is not a virtual register. */
3655 if (x == 0 || GET_CODE (x) != MEM)
3659 if (CONSTANT_P (addr)
3660 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3661 || (GET_CODE (addr) == REG
3662 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3663 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3666 /* If we should only do this if the address is valid, copy the address.
3667 We need to do this so we can undo any changes that might make the
3668 address invalid. This copy is unfortunate, but probably can't be
3672 addr = copy_rtx (addr);
3674 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3676 if (valid_only && size >= 0)
3678 unsigned HOST_WIDE_INT decl_size = size;
3680 /* Now verify that the resulting address is valid for every integer or
3681 floating-point mode up to and including SIZE bytes long. We do this
3682 since the object might be accessed in any mode and frame addresses
3685 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3686 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3687 mode = GET_MODE_WIDER_MODE (mode))
3688 if (! memory_address_p (mode, addr))
3691 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3692 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3693 mode = GET_MODE_WIDER_MODE (mode))
3694 if (! memory_address_p (mode, addr))
3698 /* Put back the address now that we have updated it and we either know
3699 it is valid or we don't care whether it is valid. */
3704 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3705 is a virtual register, return the equivalent hard register and set the
3706 offset indirectly through the pointer. Otherwise, return 0. */
3709 instantiate_new_reg (x, poffset)
3711 HOST_WIDE_INT *poffset;
3714 HOST_WIDE_INT offset;
3716 if (x == virtual_incoming_args_rtx)
3717 new = arg_pointer_rtx, offset = in_arg_offset;
3718 else if (x == virtual_stack_vars_rtx)
3719 new = frame_pointer_rtx, offset = var_offset;
3720 else if (x == virtual_stack_dynamic_rtx)
3721 new = stack_pointer_rtx, offset = dynamic_offset;
3722 else if (x == virtual_outgoing_args_rtx)
3723 new = stack_pointer_rtx, offset = out_arg_offset;
3724 else if (x == virtual_cfa_rtx)
3725 new = arg_pointer_rtx, offset = cfa_offset;
3734 /* Called when instantiate_virtual_regs has failed to update the instruction.
3735 Usually this means that non-matching instruction has been emit, however for
3736 asm statements it may be the problem in the constraints. */
3738 instantiate_virtual_regs_lossage (insn)
3741 if (asm_noperands (PATTERN (insn)) >= 0)
3743 error_for_asm (insn, "impossible constraint in `asm'");
3749 /* Given a pointer to a piece of rtx and an optional pointer to the
3750 containing object, instantiate any virtual registers present in it.
3752 If EXTRA_INSNS, we always do the replacement and generate
3753 any extra insns before OBJECT. If it zero, we do nothing if replacement
3756 Return 1 if we either had nothing to do or if we were able to do the
3757 needed replacement. Return 0 otherwise; we only return zero if
3758 EXTRA_INSNS is zero.
3760 We first try some simple transformations to avoid the creation of extra
3764 instantiate_virtual_regs_1 (loc, object, extra_insns)
3772 HOST_WIDE_INT offset = 0;
3778 /* Re-start here to avoid recursion in common cases. */
3785 /* We may have detected and deleted invalid asm statements. */
3786 if (object && INSN_P (object) && INSN_DELETED_P (object))
3789 code = GET_CODE (x);
3791 /* Check for some special cases. */
3809 /* We are allowed to set the virtual registers. This means that
3810 the actual register should receive the source minus the
3811 appropriate offset. This is used, for example, in the handling
3812 of non-local gotos. */
3813 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3815 rtx src = SET_SRC (x);
3817 /* We are setting the register, not using it, so the relevant
3818 offset is the negative of the offset to use were we using
3821 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3823 /* The only valid sources here are PLUS or REG. Just do
3824 the simplest possible thing to handle them. */
3825 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3827 instantiate_virtual_regs_lossage (object);
3832 if (GET_CODE (src) != REG)
3833 temp = force_operand (src, NULL_RTX);
3836 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3840 emit_insn_before (seq, object);
3843 if (! validate_change (object, &SET_SRC (x), temp, 0)
3845 instantiate_virtual_regs_lossage (object);
3850 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3855 /* Handle special case of virtual register plus constant. */
3856 if (CONSTANT_P (XEXP (x, 1)))
3858 rtx old, new_offset;
3860 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3861 if (GET_CODE (XEXP (x, 0)) == PLUS)
3863 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3865 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3867 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3876 #ifdef POINTERS_EXTEND_UNSIGNED
3877 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3878 we can commute the PLUS and SUBREG because pointers into the
3879 frame are well-behaved. */
3880 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3881 && GET_CODE (XEXP (x, 1)) == CONST_INT
3883 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3885 && validate_change (object, loc,
3886 plus_constant (gen_lowpart (ptr_mode,
3889 + INTVAL (XEXP (x, 1))),
3893 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3895 /* We know the second operand is a constant. Unless the
3896 first operand is a REG (which has been already checked),
3897 it needs to be checked. */
3898 if (GET_CODE (XEXP (x, 0)) != REG)
3906 new_offset = plus_constant (XEXP (x, 1), offset);
3908 /* If the new constant is zero, try to replace the sum with just
3910 if (new_offset == const0_rtx
3911 && validate_change (object, loc, new, 0))
3914 /* Next try to replace the register and new offset.
3915 There are two changes to validate here and we can't assume that
3916 in the case of old offset equals new just changing the register
3917 will yield a valid insn. In the interests of a little efficiency,
3918 however, we only call validate change once (we don't queue up the
3919 changes and then call apply_change_group). */
3923 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3924 : (XEXP (x, 0) = new,
3925 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3933 /* Otherwise copy the new constant into a register and replace
3934 constant with that register. */
3935 temp = gen_reg_rtx (Pmode);
3937 if (validate_change (object, &XEXP (x, 1), temp, 0))
3938 emit_insn_before (gen_move_insn (temp, new_offset), object);
3941 /* If that didn't work, replace this expression with a
3942 register containing the sum. */
3945 new = gen_rtx_PLUS (Pmode, new, new_offset);
3948 temp = force_operand (new, NULL_RTX);
3952 emit_insn_before (seq, object);
3953 if (! validate_change (object, loc, temp, 0)
3954 && ! validate_replace_rtx (x, temp, object))
3956 instantiate_virtual_regs_lossage (object);
3965 /* Fall through to generic two-operand expression case. */
3971 case DIV: case UDIV:
3972 case MOD: case UMOD:
3973 case AND: case IOR: case XOR:
3974 case ROTATERT: case ROTATE:
3975 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3977 case GE: case GT: case GEU: case GTU:
3978 case LE: case LT: case LEU: case LTU:
3979 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3980 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3985 /* Most cases of MEM that convert to valid addresses have already been
3986 handled by our scan of decls. The only special handling we
3987 need here is to make a copy of the rtx to ensure it isn't being
3988 shared if we have to change it to a pseudo.
3990 If the rtx is a simple reference to an address via a virtual register,
3991 it can potentially be shared. In such cases, first try to make it
3992 a valid address, which can also be shared. Otherwise, copy it and
3995 First check for common cases that need no processing. These are
3996 usually due to instantiation already being done on a previous instance
4000 if (CONSTANT_ADDRESS_P (temp)
4001 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4002 || temp == arg_pointer_rtx
4004 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4005 || temp == hard_frame_pointer_rtx
4007 || temp == frame_pointer_rtx)
4010 if (GET_CODE (temp) == PLUS
4011 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4012 && (XEXP (temp, 0) == frame_pointer_rtx
4013 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4014 || XEXP (temp, 0) == hard_frame_pointer_rtx
4016 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4017 || XEXP (temp, 0) == arg_pointer_rtx
4022 if (temp == virtual_stack_vars_rtx
4023 || temp == virtual_incoming_args_rtx
4024 || (GET_CODE (temp) == PLUS
4025 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4026 && (XEXP (temp, 0) == virtual_stack_vars_rtx
4027 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
4029 /* This MEM may be shared. If the substitution can be done without
4030 the need to generate new pseudos, we want to do it in place
4031 so all copies of the shared rtx benefit. The call below will
4032 only make substitutions if the resulting address is still
4035 Note that we cannot pass X as the object in the recursive call
4036 since the insn being processed may not allow all valid
4037 addresses. However, if we were not passed on object, we can
4038 only modify X without copying it if X will have a valid
4041 ??? Also note that this can still lose if OBJECT is an insn that
4042 has less restrictions on an address that some other insn.
4043 In that case, we will modify the shared address. This case
4044 doesn't seem very likely, though. One case where this could
4045 happen is in the case of a USE or CLOBBER reference, but we
4046 take care of that below. */
4048 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
4049 object ? object : x, 0))
4052 /* Otherwise make a copy and process that copy. We copy the entire
4053 RTL expression since it might be a PLUS which could also be
4055 *loc = x = copy_rtx (x);
4058 /* Fall through to generic unary operation case. */
4061 case STRICT_LOW_PART:
4063 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4064 case SIGN_EXTEND: case ZERO_EXTEND:
4065 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4066 case FLOAT: case FIX:
4067 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4072 case POPCOUNT: case PARITY:
4073 /* These case either have just one operand or we know that we need not
4074 check the rest of the operands. */
4080 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4081 go ahead and make the invalid one, but do it to a copy. For a REG,
4082 just make the recursive call, since there's no chance of a problem. */
4084 if ((GET_CODE (XEXP (x, 0)) == MEM
4085 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4087 || (GET_CODE (XEXP (x, 0)) == REG
4088 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4091 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4096 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4097 in front of this insn and substitute the temporary. */
4098 if ((new = instantiate_new_reg (x, &offset)) != 0)
4100 temp = plus_constant (new, offset);
4101 if (!validate_change (object, loc, temp, 0))
4107 temp = force_operand (temp, NULL_RTX);
4111 emit_insn_before (seq, object);
4112 if (! validate_change (object, loc, temp, 0)
4113 && ! validate_replace_rtx (x, temp, object))
4114 instantiate_virtual_regs_lossage (object);
4121 if (GET_CODE (XEXP (x, 0)) == REG)
4124 else if (GET_CODE (XEXP (x, 0)) == MEM)
4126 /* If we have a (addressof (mem ..)), do any instantiation inside
4127 since we know we'll be making the inside valid when we finally
4128 remove the ADDRESSOF. */
4129 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4138 /* Scan all subexpressions. */
4139 fmt = GET_RTX_FORMAT (code);
4140 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4143 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4146 else if (*fmt == 'E')
4147 for (j = 0; j < XVECLEN (x, i); j++)
4148 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4155 /* Optimization: assuming this function does not receive nonlocal gotos,
4156 delete the handlers for such, as well as the insns to establish
4157 and disestablish them. */
4163 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4165 /* Delete the handler by turning off the flag that would
4166 prevent jump_optimize from deleting it.
4167 Also permit deletion of the nonlocal labels themselves
4168 if nothing local refers to them. */
4169 if (GET_CODE (insn) == CODE_LABEL)
4173 LABEL_PRESERVE_P (insn) = 0;
4175 /* Remove it from the nonlocal_label list, to avoid confusing
4177 for (t = nonlocal_labels, last_t = 0; t;
4178 last_t = t, t = TREE_CHAIN (t))
4179 if (DECL_RTL (TREE_VALUE (t)) == insn)
4184 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4186 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4189 if (GET_CODE (insn) == INSN)
4193 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4194 if (reg_mentioned_p (t, PATTERN (insn)))
4200 || (nonlocal_goto_stack_level != 0
4201 && reg_mentioned_p (nonlocal_goto_stack_level,
4203 delete_related_insns (insn);
4208 /* Return the first insn following those generated by `assign_parms'. */
4211 get_first_nonparm_insn ()
4214 return NEXT_INSN (last_parm_insn);
4215 return get_insns ();
4218 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4219 This means a type for which function calls must pass an address to the
4220 function or get an address back from the function.
4221 EXP may be a type node or an expression (whose type is tested). */
4224 aggregate_value_p (exp)
4227 int i, regno, nregs;
4230 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4232 if (TREE_CODE (type) == VOID_TYPE)
4234 if (RETURN_IN_MEMORY (type))
4236 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4237 and thus can't be returned in registers. */
4238 if (TREE_ADDRESSABLE (type))
4240 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4242 /* Make sure we have suitable call-clobbered regs to return
4243 the value in; if not, we must return it in memory. */
4244 reg = hard_function_value (type, 0, 0);
4246 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4248 if (GET_CODE (reg) != REG)
4251 regno = REGNO (reg);
4252 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4253 for (i = 0; i < nregs; i++)
4254 if (! call_used_regs[regno + i])
4259 /* Assign RTL expressions to the function's parameters.
4260 This may involve copying them into registers and using
4261 those registers as the RTL for them. */
4264 assign_parms (fndecl)
4270 CUMULATIVE_ARGS args_so_far;
4271 enum machine_mode promoted_mode, passed_mode;
4272 enum machine_mode nominal_mode, promoted_nominal_mode;
4274 /* Total space needed so far for args on the stack,
4275 given as a constant and a tree-expression. */
4276 struct args_size stack_args_size;
4277 tree fntype = TREE_TYPE (fndecl);
4278 tree fnargs = DECL_ARGUMENTS (fndecl);
4279 /* This is used for the arg pointer when referring to stack args. */
4280 rtx internal_arg_pointer;
4281 /* This is a dummy PARM_DECL that we used for the function result if
4282 the function returns a structure. */
4283 tree function_result_decl = 0;
4284 #ifdef SETUP_INCOMING_VARARGS
4285 int varargs_setup = 0;
4287 rtx conversion_insns = 0;
4288 struct args_size alignment_pad;
4290 /* Nonzero if function takes extra anonymous args.
4291 This means the last named arg must be on the stack
4292 right before the anonymous ones. */
4294 = (TYPE_ARG_TYPES (fntype) != 0
4295 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4296 != void_type_node));
4298 current_function_stdarg = stdarg;
4300 /* If the reg that the virtual arg pointer will be translated into is
4301 not a fixed reg or is the stack pointer, make a copy of the virtual
4302 arg pointer, and address parms via the copy. The frame pointer is
4303 considered fixed even though it is not marked as such.
4305 The second time through, simply use ap to avoid generating rtx. */
4307 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4308 || ! (fixed_regs[ARG_POINTER_REGNUM]
4309 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4310 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4312 internal_arg_pointer = virtual_incoming_args_rtx;
4313 current_function_internal_arg_pointer = internal_arg_pointer;
4315 stack_args_size.constant = 0;
4316 stack_args_size.var = 0;
4318 /* If struct value address is treated as the first argument, make it so. */
4319 if (aggregate_value_p (DECL_RESULT (fndecl))
4320 && ! current_function_returns_pcc_struct
4321 && struct_value_incoming_rtx == 0)
4323 tree type = build_pointer_type (TREE_TYPE (fntype));
4325 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4327 DECL_ARG_TYPE (function_result_decl) = type;
4328 TREE_CHAIN (function_result_decl) = fnargs;
4329 fnargs = function_result_decl;
4332 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4333 parm_reg_stack_loc = (rtx *) ggc_alloc_cleared (max_parm_reg * sizeof (rtx));
4335 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4336 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4338 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, fndecl);
4341 /* We haven't yet found an argument that we must push and pretend the
4343 current_function_pretend_args_size = 0;
4345 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4347 struct args_size stack_offset;
4348 struct args_size arg_size;
4349 int passed_pointer = 0;
4350 int did_conversion = 0;
4351 tree passed_type = DECL_ARG_TYPE (parm);
4352 tree nominal_type = TREE_TYPE (parm);
4354 int last_named = 0, named_arg;
4356 /* Set LAST_NAMED if this is last named arg before last
4362 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4363 if (DECL_NAME (tem))
4369 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4370 most machines, if this is a varargs/stdarg function, then we treat
4371 the last named arg as if it were anonymous too. */
4372 named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4374 if (TREE_TYPE (parm) == error_mark_node
4375 /* This can happen after weird syntax errors
4376 or if an enum type is defined among the parms. */
4377 || TREE_CODE (parm) != PARM_DECL
4378 || passed_type == NULL)
4380 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4381 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4382 TREE_USED (parm) = 1;
4386 /* Find mode of arg as it is passed, and mode of arg
4387 as it should be during execution of this function. */
4388 passed_mode = TYPE_MODE (passed_type);
4389 nominal_mode = TYPE_MODE (nominal_type);
4391 /* If the parm's mode is VOID, its value doesn't matter,
4392 and avoid the usual things like emit_move_insn that could crash. */
4393 if (nominal_mode == VOIDmode)
4395 SET_DECL_RTL (parm, const0_rtx);
4396 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4400 /* If the parm is to be passed as a transparent union, use the
4401 type of the first field for the tests below. We have already
4402 verified that the modes are the same. */
4403 if (DECL_TRANSPARENT_UNION (parm)
4404 || (TREE_CODE (passed_type) == UNION_TYPE
4405 && TYPE_TRANSPARENT_UNION (passed_type)))
4406 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4408 /* See if this arg was passed by invisible reference. It is if
4409 it is an object whose size depends on the contents of the
4410 object itself or if the machine requires these objects be passed
4413 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4414 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4415 || TREE_ADDRESSABLE (passed_type)
4416 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4417 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4418 passed_type, named_arg)
4422 passed_type = nominal_type = build_pointer_type (passed_type);
4424 passed_mode = nominal_mode = Pmode;
4426 /* See if the frontend wants to pass this by invisible reference. */
4427 else if (passed_type != nominal_type
4428 && POINTER_TYPE_P (passed_type)
4429 && TREE_TYPE (passed_type) == nominal_type)
4431 nominal_type = passed_type;
4433 passed_mode = nominal_mode = Pmode;
4436 promoted_mode = passed_mode;
4438 #ifdef PROMOTE_FUNCTION_ARGS
4439 /* Compute the mode in which the arg is actually extended to. */
4440 unsignedp = TREE_UNSIGNED (passed_type);
4441 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4444 /* Let machine desc say which reg (if any) the parm arrives in.
4445 0 means it arrives on the stack. */
4446 #ifdef FUNCTION_INCOMING_ARG
4447 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4448 passed_type, named_arg);
4450 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4451 passed_type, named_arg);
4454 if (entry_parm == 0)
4455 promoted_mode = passed_mode;
4457 #ifdef SETUP_INCOMING_VARARGS
4458 /* If this is the last named parameter, do any required setup for
4459 varargs or stdargs. We need to know about the case of this being an
4460 addressable type, in which case we skip the registers it
4461 would have arrived in.
4463 For stdargs, LAST_NAMED will be set for two parameters, the one that
4464 is actually the last named, and the dummy parameter. We only
4465 want to do this action once.
4467 Also, indicate when RTL generation is to be suppressed. */
4468 if (last_named && !varargs_setup)
4470 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4471 current_function_pretend_args_size, 0);
4476 /* Determine parm's home in the stack,
4477 in case it arrives in the stack or we should pretend it did.
4479 Compute the stack position and rtx where the argument arrives
4482 There is one complexity here: If this was a parameter that would
4483 have been passed in registers, but wasn't only because it is
4484 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4485 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4486 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4487 0 as it was the previous time. */
4489 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4490 locate_and_pad_parm (promoted_mode, passed_type,
4491 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4494 #ifdef FUNCTION_INCOMING_ARG
4495 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4497 pretend_named) != 0,
4499 FUNCTION_ARG (args_so_far, promoted_mode,
4501 pretend_named) != 0,
4504 fndecl, &stack_args_size, &stack_offset, &arg_size,
4508 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4510 if (offset_rtx == const0_rtx)
4511 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4513 stack_parm = gen_rtx_MEM (promoted_mode,
4514 gen_rtx_PLUS (Pmode,
4515 internal_arg_pointer,
4518 set_mem_attributes (stack_parm, parm, 1);
4520 /* Set also REG_ATTRS if parameter was passed in a register. */
4522 set_reg_attrs_for_parm (entry_parm, stack_parm);
4525 /* If this parameter was passed both in registers and in the stack,
4526 use the copy on the stack. */
4527 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4530 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4531 /* If this parm was passed part in regs and part in memory,
4532 pretend it arrived entirely in memory
4533 by pushing the register-part onto the stack.
4535 In the special case of a DImode or DFmode that is split,
4536 we could put it together in a pseudoreg directly,
4537 but for now that's not worth bothering with. */
4541 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4542 passed_type, named_arg);
4546 #if defined (REG_PARM_STACK_SPACE) && !defined (MAYBE_REG_PARM_STACK_SPACE)
4547 /* When REG_PARM_STACK_SPACE is nonzero, stack space for
4548 split parameters was allocated by our caller, so we
4549 won't be pushing it in the prolog. */
4550 if (REG_PARM_STACK_SPACE (fndecl) == 0)
4552 current_function_pretend_args_size
4553 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4554 / (PARM_BOUNDARY / BITS_PER_UNIT)
4555 * (PARM_BOUNDARY / BITS_PER_UNIT));
4557 /* Handle calls that pass values in multiple non-contiguous
4558 locations. The Irix 6 ABI has examples of this. */
4559 if (GET_CODE (entry_parm) == PARALLEL)
4560 emit_group_store (validize_mem (stack_parm), entry_parm,
4561 int_size_in_bytes (TREE_TYPE (parm)));
4564 move_block_from_reg (REGNO (entry_parm),
4565 validize_mem (stack_parm), nregs,
4566 int_size_in_bytes (TREE_TYPE (parm)));
4568 entry_parm = stack_parm;
4573 /* If we didn't decide this parm came in a register,
4574 by default it came on the stack. */
4575 if (entry_parm == 0)
4576 entry_parm = stack_parm;
4578 /* Record permanently how this parm was passed. */
4579 DECL_INCOMING_RTL (parm) = entry_parm;
4581 /* If there is actually space on the stack for this parm,
4582 count it in stack_args_size; otherwise set stack_parm to 0
4583 to indicate there is no preallocated stack slot for the parm. */
4585 if (entry_parm == stack_parm
4586 || (GET_CODE (entry_parm) == PARALLEL
4587 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4588 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4589 /* On some machines, even if a parm value arrives in a register
4590 there is still an (uninitialized) stack slot allocated for it.
4592 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4593 whether this parameter already has a stack slot allocated,
4594 because an arg block exists only if current_function_args_size
4595 is larger than some threshold, and we haven't calculated that
4596 yet. So, for now, we just assume that stack slots never exist
4598 || REG_PARM_STACK_SPACE (fndecl) > 0
4602 stack_args_size.constant += arg_size.constant;
4604 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4607 /* No stack slot was pushed for this parm. */
4610 /* Update info on where next arg arrives in registers. */
4612 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4613 passed_type, named_arg);
4615 /* If we can't trust the parm stack slot to be aligned enough
4616 for its ultimate type, don't use that slot after entry.
4617 We'll make another stack slot, if we need one. */
4619 unsigned int thisparm_boundary
4620 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4622 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4626 /* If parm was passed in memory, and we need to convert it on entry,
4627 don't store it back in that same slot. */
4629 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4632 /* When an argument is passed in multiple locations, we can't
4633 make use of this information, but we can save some copying if
4634 the whole argument is passed in a single register. */
4635 if (GET_CODE (entry_parm) == PARALLEL
4636 && nominal_mode != BLKmode && passed_mode != BLKmode)
4638 int i, len = XVECLEN (entry_parm, 0);
4640 for (i = 0; i < len; i++)
4641 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4642 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4643 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4645 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4647 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4648 DECL_INCOMING_RTL (parm) = entry_parm;
4653 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4654 in the mode in which it arrives.
4655 STACK_PARM is an RTX for a stack slot where the parameter can live
4656 during the function (in case we want to put it there).
4657 STACK_PARM is 0 if no stack slot was pushed for it.
4659 Now output code if necessary to convert ENTRY_PARM to
4660 the type in which this function declares it,
4661 and store that result in an appropriate place,
4662 which may be a pseudo reg, may be STACK_PARM,
4663 or may be a local stack slot if STACK_PARM is 0.
4665 Set DECL_RTL to that place. */
4667 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4669 /* If a BLKmode arrives in registers, copy it to a stack slot.
4670 Handle calls that pass values in multiple non-contiguous
4671 locations. The Irix 6 ABI has examples of this. */
4672 if (GET_CODE (entry_parm) == REG
4673 || GET_CODE (entry_parm) == PARALLEL)
4676 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4679 /* Note that we will be storing an integral number of words.
4680 So we have to be careful to ensure that we allocate an
4681 integral number of words. We do this below in the
4682 assign_stack_local if space was not allocated in the argument
4683 list. If it was, this will not work if PARM_BOUNDARY is not
4684 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4685 if it becomes a problem. */
4687 if (stack_parm == 0)
4690 = assign_stack_local (GET_MODE (entry_parm),
4692 set_mem_attributes (stack_parm, parm, 1);
4695 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4698 /* Handle calls that pass values in multiple non-contiguous
4699 locations. The Irix 6 ABI has examples of this. */
4700 if (GET_CODE (entry_parm) == PARALLEL)
4701 emit_group_store (validize_mem (stack_parm), entry_parm,
4702 int_size_in_bytes (TREE_TYPE (parm)));
4704 move_block_from_reg (REGNO (entry_parm),
4705 validize_mem (stack_parm),
4706 size_stored / UNITS_PER_WORD,
4707 int_size_in_bytes (TREE_TYPE (parm)));
4709 SET_DECL_RTL (parm, stack_parm);
4711 else if (! ((! optimize
4712 && ! DECL_REGISTER (parm))
4713 || TREE_SIDE_EFFECTS (parm)
4714 /* If -ffloat-store specified, don't put explicit
4715 float variables into registers. */
4716 || (flag_float_store
4717 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4718 /* Always assign pseudo to structure return or item passed
4719 by invisible reference. */
4720 || passed_pointer || parm == function_result_decl)
4722 /* Store the parm in a pseudoregister during the function, but we
4723 may need to do it in a wider mode. */
4726 unsigned int regno, regnoi = 0, regnor = 0;
4728 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4730 promoted_nominal_mode
4731 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4733 parmreg = gen_reg_rtx (promoted_nominal_mode);
4734 mark_user_reg (parmreg);
4736 /* If this was an item that we received a pointer to, set DECL_RTL
4740 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4742 set_mem_attributes (x, parm, 1);
4743 SET_DECL_RTL (parm, x);
4747 SET_DECL_RTL (parm, parmreg);
4748 maybe_set_unchanging (DECL_RTL (parm), parm);
4751 /* Copy the value into the register. */
4752 if (nominal_mode != passed_mode
4753 || promoted_nominal_mode != promoted_mode)
4756 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4757 mode, by the caller. We now have to convert it to
4758 NOMINAL_MODE, if different. However, PARMREG may be in
4759 a different mode than NOMINAL_MODE if it is being stored
4762 If ENTRY_PARM is a hard register, it might be in a register
4763 not valid for operating in its mode (e.g., an odd-numbered
4764 register for a DFmode). In that case, moves are the only
4765 thing valid, so we can't do a convert from there. This
4766 occurs when the calling sequence allow such misaligned
4769 In addition, the conversion may involve a call, which could
4770 clobber parameters which haven't been copied to pseudo
4771 registers yet. Therefore, we must first copy the parm to
4772 a pseudo reg here, and save the conversion until after all
4773 parameters have been moved. */
4775 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4777 emit_move_insn (tempreg, validize_mem (entry_parm));
4779 push_to_sequence (conversion_insns);
4780 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4782 if (GET_CODE (tempreg) == SUBREG
4783 && GET_MODE (tempreg) == nominal_mode
4784 && GET_CODE (SUBREG_REG (tempreg)) == REG
4785 && nominal_mode == passed_mode
4786 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4787 && GET_MODE_SIZE (GET_MODE (tempreg))
4788 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4790 /* The argument is already sign/zero extended, so note it
4792 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4793 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4796 /* TREE_USED gets set erroneously during expand_assignment. */
4797 save_tree_used = TREE_USED (parm);
4798 expand_assignment (parm,
4799 make_tree (nominal_type, tempreg), 0, 0);
4800 TREE_USED (parm) = save_tree_used;
4801 conversion_insns = get_insns ();
4806 emit_move_insn (parmreg, validize_mem (entry_parm));
4808 /* If we were passed a pointer but the actual value
4809 can safely live in a register, put it in one. */
4810 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4811 /* If by-reference argument was promoted, demote it. */
4812 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4814 && ! DECL_REGISTER (parm))
4815 || TREE_SIDE_EFFECTS (parm)
4816 /* If -ffloat-store specified, don't put explicit
4817 float variables into registers. */
4818 || (flag_float_store
4819 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4821 /* We can't use nominal_mode, because it will have been set to
4822 Pmode above. We must use the actual mode of the parm. */
4823 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4824 mark_user_reg (parmreg);
4825 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4827 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4828 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4829 push_to_sequence (conversion_insns);
4830 emit_move_insn (tempreg, DECL_RTL (parm));
4832 convert_to_mode (GET_MODE (parmreg),
4835 emit_move_insn (parmreg, DECL_RTL (parm));
4836 conversion_insns = get_insns();
4841 emit_move_insn (parmreg, DECL_RTL (parm));
4842 SET_DECL_RTL (parm, parmreg);
4843 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4847 #ifdef FUNCTION_ARG_CALLEE_COPIES
4848 /* If we are passed an arg by reference and it is our responsibility
4849 to make a copy, do it now.
4850 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4851 original argument, so we must recreate them in the call to
4852 FUNCTION_ARG_CALLEE_COPIES. */
4853 /* ??? Later add code to handle the case that if the argument isn't
4854 modified, don't do the copy. */
4856 else if (passed_pointer
4857 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4858 TYPE_MODE (DECL_ARG_TYPE (parm)),
4859 DECL_ARG_TYPE (parm),
4861 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4864 tree type = DECL_ARG_TYPE (parm);
4866 /* This sequence may involve a library call perhaps clobbering
4867 registers that haven't been copied to pseudos yet. */
4869 push_to_sequence (conversion_insns);
4871 if (!COMPLETE_TYPE_P (type)
4872 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4873 /* This is a variable sized object. */
4874 copy = gen_rtx_MEM (BLKmode,
4875 allocate_dynamic_stack_space
4876 (expr_size (parm), NULL_RTX,
4877 TYPE_ALIGN (type)));
4879 copy = assign_stack_temp (TYPE_MODE (type),
4880 int_size_in_bytes (type), 1);
4881 set_mem_attributes (copy, parm, 1);
4883 store_expr (parm, copy, 0);
4884 emit_move_insn (parmreg, XEXP (copy, 0));
4885 conversion_insns = get_insns ();
4889 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4891 /* In any case, record the parm's desired stack location
4892 in case we later discover it must live in the stack.
4894 If it is a COMPLEX value, store the stack location for both
4897 if (GET_CODE (parmreg) == CONCAT)
4898 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4900 regno = REGNO (parmreg);
4902 if (regno >= max_parm_reg)
4905 int old_max_parm_reg = max_parm_reg;
4907 /* It's slow to expand this one register at a time,
4908 but it's also rare and we need max_parm_reg to be
4909 precisely correct. */
4910 max_parm_reg = regno + 1;
4911 new = (rtx *) ggc_realloc (parm_reg_stack_loc,
4912 max_parm_reg * sizeof (rtx));
4913 memset ((char *) (new + old_max_parm_reg), 0,
4914 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4915 parm_reg_stack_loc = new;
4918 if (GET_CODE (parmreg) == CONCAT)
4920 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4922 regnor = REGNO (gen_realpart (submode, parmreg));
4923 regnoi = REGNO (gen_imagpart (submode, parmreg));
4925 if (stack_parm != 0)
4927 parm_reg_stack_loc[regnor]
4928 = gen_realpart (submode, stack_parm);
4929 parm_reg_stack_loc[regnoi]
4930 = gen_imagpart (submode, stack_parm);
4934 parm_reg_stack_loc[regnor] = 0;
4935 parm_reg_stack_loc[regnoi] = 0;
4939 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4941 /* Mark the register as eliminable if we did no conversion
4942 and it was copied from memory at a fixed offset,
4943 and the arg pointer was not copied to a pseudo-reg.
4944 If the arg pointer is a pseudo reg or the offset formed
4945 an invalid address, such memory-equivalences
4946 as we make here would screw up life analysis for it. */
4947 if (nominal_mode == passed_mode
4950 && GET_CODE (stack_parm) == MEM
4951 && stack_offset.var == 0
4952 && reg_mentioned_p (virtual_incoming_args_rtx,
4953 XEXP (stack_parm, 0)))
4955 rtx linsn = get_last_insn ();
4958 /* Mark complex types separately. */
4959 if (GET_CODE (parmreg) == CONCAT)
4960 /* Scan backwards for the set of the real and
4962 for (sinsn = linsn; sinsn != 0;
4963 sinsn = prev_nonnote_insn (sinsn))
4965 set = single_set (sinsn);
4967 && SET_DEST (set) == regno_reg_rtx [regnoi])
4969 = gen_rtx_EXPR_LIST (REG_EQUIV,
4970 parm_reg_stack_loc[regnoi],
4973 && SET_DEST (set) == regno_reg_rtx [regnor])
4975 = gen_rtx_EXPR_LIST (REG_EQUIV,
4976 parm_reg_stack_loc[regnor],
4979 else if ((set = single_set (linsn)) != 0
4980 && SET_DEST (set) == parmreg)
4982 = gen_rtx_EXPR_LIST (REG_EQUIV,
4983 stack_parm, REG_NOTES (linsn));
4986 /* For pointer data type, suggest pointer register. */
4987 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4988 mark_reg_pointer (parmreg,
4989 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4991 /* If something wants our address, try to use ADDRESSOF. */
4992 if (TREE_ADDRESSABLE (parm))
4994 /* If we end up putting something into the stack,
4995 fixup_var_refs_insns will need to make a pass over
4996 all the instructions. It looks through the pending
4997 sequences -- but it can't see the ones in the
4998 CONVERSION_INSNS, if they're not on the sequence
4999 stack. So, we go back to that sequence, just so that
5000 the fixups will happen. */
5001 push_to_sequence (conversion_insns);
5002 put_var_into_stack (parm, /*rescan=*/true);
5003 conversion_insns = get_insns ();
5009 /* Value must be stored in the stack slot STACK_PARM
5010 during function execution. */
5012 if (promoted_mode != nominal_mode)
5014 /* Conversion is required. */
5015 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
5017 emit_move_insn (tempreg, validize_mem (entry_parm));
5019 push_to_sequence (conversion_insns);
5020 entry_parm = convert_to_mode (nominal_mode, tempreg,
5021 TREE_UNSIGNED (TREE_TYPE (parm)));
5023 /* ??? This may need a big-endian conversion on sparc64. */
5024 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
5026 conversion_insns = get_insns ();
5031 if (entry_parm != stack_parm)
5033 if (stack_parm == 0)
5036 = assign_stack_local (GET_MODE (entry_parm),
5037 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
5038 set_mem_attributes (stack_parm, parm, 1);
5041 if (promoted_mode != nominal_mode)
5043 push_to_sequence (conversion_insns);
5044 emit_move_insn (validize_mem (stack_parm),
5045 validize_mem (entry_parm));
5046 conversion_insns = get_insns ();
5050 emit_move_insn (validize_mem (stack_parm),
5051 validize_mem (entry_parm));
5054 SET_DECL_RTL (parm, stack_parm);
5058 /* Output all parameter conversion instructions (possibly including calls)
5059 now that all parameters have been copied out of hard registers. */
5060 emit_insn (conversion_insns);
5062 /* If we are receiving a struct value address as the first argument, set up
5063 the RTL for the function result. As this might require code to convert
5064 the transmitted address to Pmode, we do this here to ensure that possible
5065 preliminary conversions of the address have been emitted already. */
5066 if (function_result_decl)
5068 tree result = DECL_RESULT (fndecl);
5069 rtx addr = DECL_RTL (function_result_decl);
5072 #ifdef POINTERS_EXTEND_UNSIGNED
5073 if (GET_MODE (addr) != Pmode)
5074 addr = convert_memory_address (Pmode, addr);
5077 x = gen_rtx_MEM (DECL_MODE (result), addr);
5078 set_mem_attributes (x, result, 1);
5079 SET_DECL_RTL (result, x);
5082 last_parm_insn = get_last_insn ();
5084 current_function_args_size = stack_args_size.constant;
5086 /* Adjust function incoming argument size for alignment and
5089 #ifdef REG_PARM_STACK_SPACE
5090 #ifndef MAYBE_REG_PARM_STACK_SPACE
5091 current_function_args_size = MAX (current_function_args_size,
5092 REG_PARM_STACK_SPACE (fndecl));
5096 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
5098 current_function_args_size
5099 = ((current_function_args_size + STACK_BYTES - 1)
5100 / STACK_BYTES) * STACK_BYTES;
5102 #ifdef ARGS_GROW_DOWNWARD
5103 current_function_arg_offset_rtx
5104 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5105 : expand_expr (size_diffop (stack_args_size.var,
5106 size_int (-stack_args_size.constant)),
5107 NULL_RTX, VOIDmode, 0));
5109 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5112 /* See how many bytes, if any, of its args a function should try to pop
5115 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5116 current_function_args_size);
5118 /* For stdarg.h function, save info about
5119 regs and stack space used by the named args. */
5121 current_function_args_info = args_so_far;
5123 /* Set the rtx used for the function return value. Put this in its
5124 own variable so any optimizers that need this information don't have
5125 to include tree.h. Do this here so it gets done when an inlined
5126 function gets output. */
5128 current_function_return_rtx
5129 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5130 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5132 /* If scalar return value was computed in a pseudo-reg, or was a named
5133 return value that got dumped to the stack, copy that to the hard
5135 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5137 tree decl_result = DECL_RESULT (fndecl);
5138 rtx decl_rtl = DECL_RTL (decl_result);
5140 if (REG_P (decl_rtl)
5141 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5142 : DECL_REGISTER (decl_result))
5146 #ifdef FUNCTION_OUTGOING_VALUE
5147 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5150 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5153 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5154 /* The delay slot scheduler assumes that current_function_return_rtx
5155 holds the hard register containing the return value, not a
5156 temporary pseudo. */
5157 current_function_return_rtx = real_decl_rtl;
5162 /* Indicate whether REGNO is an incoming argument to the current function
5163 that was promoted to a wider mode. If so, return the RTX for the
5164 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5165 that REGNO is promoted from and whether the promotion was signed or
5168 #ifdef PROMOTE_FUNCTION_ARGS
5171 promoted_input_arg (regno, pmode, punsignedp)
5173 enum machine_mode *pmode;
5178 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5179 arg = TREE_CHAIN (arg))
5180 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5181 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5182 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5184 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5185 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5187 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5188 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5189 && mode != DECL_MODE (arg))
5191 *pmode = DECL_MODE (arg);
5192 *punsignedp = unsignedp;
5193 return DECL_INCOMING_RTL (arg);
5202 /* Compute the size and offset from the start of the stacked arguments for a
5203 parm passed in mode PASSED_MODE and with type TYPE.
5205 INITIAL_OFFSET_PTR points to the current offset into the stacked
5208 The starting offset and size for this parm are returned in *OFFSET_PTR
5209 and *ARG_SIZE_PTR, respectively.
5211 IN_REGS is nonzero if the argument will be passed in registers. It will
5212 never be set if REG_PARM_STACK_SPACE is not defined.
5214 FNDECL is the function in which the argument was defined.
5216 There are two types of rounding that are done. The first, controlled by
5217 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5218 list to be aligned to the specific boundary (in bits). This rounding
5219 affects the initial and starting offsets, but not the argument size.
5221 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5222 optionally rounds the size of the parm to PARM_BOUNDARY. The
5223 initial offset is not affected by this rounding, while the size always
5224 is and the starting offset may be. */
5226 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
5227 initial_offset_ptr is positive because locate_and_pad_parm's
5228 callers pass in the total size of args so far as
5229 initial_offset_ptr. arg_size_ptr is always positive. */
5232 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
5233 initial_offset_ptr, offset_ptr, arg_size_ptr,
5235 enum machine_mode passed_mode;
5237 int in_regs ATTRIBUTE_UNUSED;
5238 tree fndecl ATTRIBUTE_UNUSED;
5239 struct args_size *initial_offset_ptr;
5240 struct args_size *offset_ptr;
5241 struct args_size *arg_size_ptr;
5242 struct args_size *alignment_pad;
5246 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5247 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5248 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5249 #ifdef ARGS_GROW_DOWNWARD
5253 #ifdef REG_PARM_STACK_SPACE
5254 /* If we have found a stack parm before we reach the end of the
5255 area reserved for registers, skip that area. */
5258 int reg_parm_stack_space = 0;
5260 #ifdef MAYBE_REG_PARM_STACK_SPACE
5261 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5263 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5265 if (reg_parm_stack_space > 0)
5267 if (initial_offset_ptr->var)
5269 initial_offset_ptr->var
5270 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5271 ssize_int (reg_parm_stack_space));
5272 initial_offset_ptr->constant = 0;
5274 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5275 initial_offset_ptr->constant = reg_parm_stack_space;
5278 #endif /* REG_PARM_STACK_SPACE */
5280 arg_size_ptr->var = 0;
5281 arg_size_ptr->constant = 0;
5282 alignment_pad->var = 0;
5283 alignment_pad->constant = 0;
5285 #ifdef ARGS_GROW_DOWNWARD
5286 if (initial_offset_ptr->var)
5288 offset_ptr->constant = 0;
5289 offset_ptr->var = size_binop (MINUS_EXPR, ssize_int (0),
5290 initial_offset_ptr->var);
5294 offset_ptr->constant = -initial_offset_ptr->constant;
5295 offset_ptr->var = 0;
5298 if (where_pad != none
5299 && (!host_integerp (sizetree, 1)
5300 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5301 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
5302 SUB_PARM_SIZE (*offset_ptr, s2);
5305 #ifdef REG_PARM_STACK_SPACE
5306 || REG_PARM_STACK_SPACE (fndecl) > 0
5309 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5311 if (initial_offset_ptr->var)
5312 arg_size_ptr->var = size_binop (MINUS_EXPR,
5313 size_binop (MINUS_EXPR,
5315 initial_offset_ptr->var),
5319 arg_size_ptr->constant = (-initial_offset_ptr->constant
5320 - offset_ptr->constant);
5322 /* Pad_below needs the pre-rounded size to know how much to pad below.
5323 We only pad parameters which are not in registers as they have their
5324 padding done elsewhere. */
5325 if (where_pad == downward
5327 pad_below (offset_ptr, passed_mode, sizetree);
5329 #else /* !ARGS_GROW_DOWNWARD */
5331 #ifdef REG_PARM_STACK_SPACE
5332 || REG_PARM_STACK_SPACE (fndecl) > 0
5335 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5336 *offset_ptr = *initial_offset_ptr;
5338 #ifdef PUSH_ROUNDING
5339 if (passed_mode != BLKmode)
5340 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5343 /* Pad_below needs the pre-rounded size to know how much to pad below
5344 so this must be done before rounding up. */
5345 if (where_pad == downward
5346 /* However, BLKmode args passed in regs have their padding done elsewhere.
5347 The stack slot must be able to hold the entire register. */
5348 && !(in_regs && passed_mode == BLKmode))
5349 pad_below (offset_ptr, passed_mode, sizetree);
5351 if (where_pad != none
5352 && (!host_integerp (sizetree, 1)
5353 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5354 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5356 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5357 #endif /* ARGS_GROW_DOWNWARD */
5360 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5361 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5364 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5365 struct args_size *offset_ptr;
5367 struct args_size *alignment_pad;
5369 tree save_var = NULL_TREE;
5370 HOST_WIDE_INT save_constant = 0;
5372 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5374 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5376 save_var = offset_ptr->var;
5377 save_constant = offset_ptr->constant;
5380 alignment_pad->var = NULL_TREE;
5381 alignment_pad->constant = 0;
5383 if (boundary > BITS_PER_UNIT)
5385 if (offset_ptr->var)
5388 #ifdef ARGS_GROW_DOWNWARD
5393 (ARGS_SIZE_TREE (*offset_ptr),
5394 boundary / BITS_PER_UNIT);
5395 offset_ptr->constant = 0; /*?*/
5396 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5397 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5402 offset_ptr->constant =
5403 #ifdef ARGS_GROW_DOWNWARD
5404 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5406 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5408 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5409 alignment_pad->constant = offset_ptr->constant - save_constant;
5415 pad_below (offset_ptr, passed_mode, sizetree)
5416 struct args_size *offset_ptr;
5417 enum machine_mode passed_mode;
5420 if (passed_mode != BLKmode)
5422 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5423 offset_ptr->constant
5424 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5425 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5426 - GET_MODE_SIZE (passed_mode));
5430 if (TREE_CODE (sizetree) != INTEGER_CST
5431 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5433 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5434 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5436 ADD_PARM_SIZE (*offset_ptr, s2);
5437 SUB_PARM_SIZE (*offset_ptr, sizetree);
5442 /* Walk the tree of blocks describing the binding levels within a function
5443 and warn about uninitialized variables.
5444 This is done after calling flow_analysis and before global_alloc
5445 clobbers the pseudo-regs to hard regs. */
5448 uninitialized_vars_warning (block)
5452 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5454 if (warn_uninitialized
5455 && TREE_CODE (decl) == VAR_DECL
5456 /* These warnings are unreliable for and aggregates
5457 because assigning the fields one by one can fail to convince
5458 flow.c that the entire aggregate was initialized.
5459 Unions are troublesome because members may be shorter. */
5460 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5461 && DECL_RTL (decl) != 0
5462 && GET_CODE (DECL_RTL (decl)) == REG
5463 /* Global optimizations can make it difficult to determine if a
5464 particular variable has been initialized. However, a VAR_DECL
5465 with a nonzero DECL_INITIAL had an initializer, so do not
5466 claim it is potentially uninitialized.
5468 We do not care about the actual value in DECL_INITIAL, so we do
5469 not worry that it may be a dangling pointer. */
5470 && DECL_INITIAL (decl) == NULL_TREE
5471 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5472 warning_with_decl (decl,
5473 "`%s' might be used uninitialized in this function");
5475 && TREE_CODE (decl) == VAR_DECL
5476 && DECL_RTL (decl) != 0
5477 && GET_CODE (DECL_RTL (decl)) == REG
5478 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5479 warning_with_decl (decl,
5480 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5482 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5483 uninitialized_vars_warning (sub);
5486 /* Do the appropriate part of uninitialized_vars_warning
5487 but for arguments instead of local variables. */
5490 setjmp_args_warning ()
5493 for (decl = DECL_ARGUMENTS (current_function_decl);
5494 decl; decl = TREE_CHAIN (decl))
5495 if (DECL_RTL (decl) != 0
5496 && GET_CODE (DECL_RTL (decl)) == REG
5497 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5498 warning_with_decl (decl,
5499 "argument `%s' might be clobbered by `longjmp' or `vfork'");
5502 /* If this function call setjmp, put all vars into the stack
5503 unless they were declared `register'. */
5506 setjmp_protect (block)
5510 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5511 if ((TREE_CODE (decl) == VAR_DECL
5512 || TREE_CODE (decl) == PARM_DECL)
5513 && DECL_RTL (decl) != 0
5514 && (GET_CODE (DECL_RTL (decl)) == REG
5515 || (GET_CODE (DECL_RTL (decl)) == MEM
5516 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5517 /* If this variable came from an inline function, it must be
5518 that its life doesn't overlap the setjmp. If there was a
5519 setjmp in the function, it would already be in memory. We
5520 must exclude such variable because their DECL_RTL might be
5521 set to strange things such as virtual_stack_vars_rtx. */
5522 && ! DECL_FROM_INLINE (decl)
5524 #ifdef NON_SAVING_SETJMP
5525 /* If longjmp doesn't restore the registers,
5526 don't put anything in them. */
5530 ! DECL_REGISTER (decl)))
5531 put_var_into_stack (decl, /*rescan=*/true);
5532 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5533 setjmp_protect (sub);
5536 /* Like the previous function, but for args instead of local variables. */
5539 setjmp_protect_args ()
5542 for (decl = DECL_ARGUMENTS (current_function_decl);
5543 decl; decl = TREE_CHAIN (decl))
5544 if ((TREE_CODE (decl) == VAR_DECL
5545 || TREE_CODE (decl) == PARM_DECL)
5546 && DECL_RTL (decl) != 0
5547 && (GET_CODE (DECL_RTL (decl)) == REG
5548 || (GET_CODE (DECL_RTL (decl)) == MEM
5549 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5551 /* If longjmp doesn't restore the registers,
5552 don't put anything in them. */
5553 #ifdef NON_SAVING_SETJMP
5557 ! DECL_REGISTER (decl)))
5558 put_var_into_stack (decl, /*rescan=*/true);
5561 /* Return the context-pointer register corresponding to DECL,
5562 or 0 if it does not need one. */
5565 lookup_static_chain (decl)
5568 tree context = decl_function_context (decl);
5572 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5575 /* We treat inline_function_decl as an alias for the current function
5576 because that is the inline function whose vars, types, etc.
5577 are being merged into the current function.
5578 See expand_inline_function. */
5579 if (context == current_function_decl || context == inline_function_decl)
5580 return virtual_stack_vars_rtx;
5582 for (link = context_display; link; link = TREE_CHAIN (link))
5583 if (TREE_PURPOSE (link) == context)
5584 return RTL_EXPR_RTL (TREE_VALUE (link));
5589 /* Convert a stack slot address ADDR for variable VAR
5590 (from a containing function)
5591 into an address valid in this function (using a static chain). */
5594 fix_lexical_addr (addr, var)
5599 HOST_WIDE_INT displacement;
5600 tree context = decl_function_context (var);
5601 struct function *fp;
5604 /* If this is the present function, we need not do anything. */
5605 if (context == current_function_decl || context == inline_function_decl)
5608 fp = find_function_data (context);
5610 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5611 addr = XEXP (XEXP (addr, 0), 0);
5613 /* Decode given address as base reg plus displacement. */
5614 if (GET_CODE (addr) == REG)
5615 basereg = addr, displacement = 0;
5616 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5617 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5621 /* We accept vars reached via the containing function's
5622 incoming arg pointer and via its stack variables pointer. */
5623 if (basereg == fp->internal_arg_pointer)
5625 /* If reached via arg pointer, get the arg pointer value
5626 out of that function's stack frame.
5628 There are two cases: If a separate ap is needed, allocate a
5629 slot in the outer function for it and dereference it that way.
5630 This is correct even if the real ap is actually a pseudo.
5631 Otherwise, just adjust the offset from the frame pointer to
5634 #ifdef NEED_SEPARATE_AP
5637 addr = get_arg_pointer_save_area (fp);
5638 addr = fix_lexical_addr (XEXP (addr, 0), var);
5639 addr = memory_address (Pmode, addr);
5641 base = gen_rtx_MEM (Pmode, addr);
5642 set_mem_alias_set (base, get_frame_alias_set ());
5643 base = copy_to_reg (base);
5645 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5646 base = lookup_static_chain (var);
5650 else if (basereg == virtual_stack_vars_rtx)
5652 /* This is the same code as lookup_static_chain, duplicated here to
5653 avoid an extra call to decl_function_context. */
5656 for (link = context_display; link; link = TREE_CHAIN (link))
5657 if (TREE_PURPOSE (link) == context)
5659 base = RTL_EXPR_RTL (TREE_VALUE (link));
5667 /* Use same offset, relative to appropriate static chain or argument
5669 return plus_constant (base, displacement);
5672 /* Return the address of the trampoline for entering nested fn FUNCTION.
5673 If necessary, allocate a trampoline (in the stack frame)
5674 and emit rtl to initialize its contents (at entry to this function). */
5677 trampoline_address (function)
5683 struct function *fp;
5686 /* Find an existing trampoline and return it. */
5687 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5688 if (TREE_PURPOSE (link) == function)
5690 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5692 for (fp = outer_function_chain; fp; fp = fp->outer)
5693 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5694 if (TREE_PURPOSE (link) == function)
5696 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5698 return adjust_trampoline_addr (tramp);
5701 /* None exists; we must make one. */
5703 /* Find the `struct function' for the function containing FUNCTION. */
5705 fn_context = decl_function_context (function);
5706 if (fn_context != current_function_decl
5707 && fn_context != inline_function_decl)
5708 fp = find_function_data (fn_context);
5710 /* Allocate run-time space for this trampoline
5711 (usually in the defining function's stack frame). */
5712 #ifdef ALLOCATE_TRAMPOLINE
5713 tramp = ALLOCATE_TRAMPOLINE (fp);
5715 /* If rounding needed, allocate extra space
5716 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5717 #define TRAMPOLINE_REAL_SIZE \
5718 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5719 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5723 /* Record the trampoline for reuse and note it for later initialization
5724 by expand_function_end. */
5727 rtlexp = make_node (RTL_EXPR);
5728 RTL_EXPR_RTL (rtlexp) = tramp;
5729 fp->x_trampoline_list = tree_cons (function, rtlexp,
5730 fp->x_trampoline_list);
5734 /* Make the RTL_EXPR node temporary, not momentary, so that the
5735 trampoline_list doesn't become garbage. */
5736 rtlexp = make_node (RTL_EXPR);
5738 RTL_EXPR_RTL (rtlexp) = tramp;
5739 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5742 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5743 return adjust_trampoline_addr (tramp);
5746 /* Given a trampoline address,
5747 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5750 round_trampoline_addr (tramp)
5753 /* Round address up to desired boundary. */
5754 rtx temp = gen_reg_rtx (Pmode);
5755 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
5756 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5758 temp = expand_simple_binop (Pmode, PLUS, tramp, addend,
5759 temp, 0, OPTAB_LIB_WIDEN);
5760 tramp = expand_simple_binop (Pmode, AND, temp, mask,
5761 temp, 0, OPTAB_LIB_WIDEN);
5766 /* Given a trampoline address, round it then apply any
5767 platform-specific adjustments so that the result can be used for a
5771 adjust_trampoline_addr (tramp)
5774 tramp = round_trampoline_addr (tramp);
5775 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5776 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5781 /* Put all this function's BLOCK nodes including those that are chained
5782 onto the first block into a vector, and return it.
5783 Also store in each NOTE for the beginning or end of a block
5784 the index of that block in the vector.
5785 The arguments are BLOCK, the chain of top-level blocks of the function,
5786 and INSNS, the insn chain of the function. */
5792 tree *block_vector, *last_block_vector;
5794 tree block = DECL_INITIAL (current_function_decl);
5799 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5800 depth-first order. */
5801 block_vector = get_block_vector (block, &n_blocks);
5802 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5804 last_block_vector = identify_blocks_1 (get_insns (),
5806 block_vector + n_blocks,
5809 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5810 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5811 if (0 && last_block_vector != block_vector + n_blocks)
5814 free (block_vector);
5818 /* Subroutine of identify_blocks. Do the block substitution on the
5819 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5821 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5822 BLOCK_VECTOR is incremented for each block seen. */
5825 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5828 tree *end_block_vector;
5829 tree *orig_block_stack;
5832 tree *block_stack = orig_block_stack;
5834 for (insn = insns; insn; insn = NEXT_INSN (insn))
5836 if (GET_CODE (insn) == NOTE)
5838 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5842 /* If there are more block notes than BLOCKs, something
5844 if (block_vector == end_block_vector)
5847 b = *block_vector++;
5848 NOTE_BLOCK (insn) = b;
5851 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5853 /* If there are more NOTE_INSN_BLOCK_ENDs than
5854 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5855 if (block_stack == orig_block_stack)
5858 NOTE_BLOCK (insn) = *--block_stack;
5861 else if (GET_CODE (insn) == CALL_INSN
5862 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5864 rtx cp = PATTERN (insn);
5866 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5867 end_block_vector, block_stack);
5869 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5870 end_block_vector, block_stack);
5872 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5873 end_block_vector, block_stack);
5877 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5878 something is badly wrong. */
5879 if (block_stack != orig_block_stack)
5882 return block_vector;
5885 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5886 and create duplicate blocks. */
5887 /* ??? Need an option to either create block fragments or to create
5888 abstract origin duplicates of a source block. It really depends
5889 on what optimization has been performed. */
5894 tree block = DECL_INITIAL (current_function_decl);
5895 varray_type block_stack;
5897 if (block == NULL_TREE)
5900 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5902 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
5903 reorder_blocks_0 (block);
5905 /* Prune the old trees away, so that they don't get in the way. */
5906 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5907 BLOCK_CHAIN (block) = NULL_TREE;
5909 /* Recreate the block tree from the note nesting. */
5910 reorder_blocks_1 (get_insns (), block, &block_stack);
5911 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5913 /* Remove deleted blocks from the block fragment chains. */
5914 reorder_fix_fragments (block);
5917 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
5920 reorder_blocks_0 (block)
5925 TREE_ASM_WRITTEN (block) = 0;
5926 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
5927 block = BLOCK_CHAIN (block);
5932 reorder_blocks_1 (insns, current_block, p_block_stack)
5935 varray_type *p_block_stack;
5939 for (insn = insns; insn; insn = NEXT_INSN (insn))
5941 if (GET_CODE (insn) == NOTE)
5943 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5945 tree block = NOTE_BLOCK (insn);
5947 /* If we have seen this block before, that means it now
5948 spans multiple address regions. Create a new fragment. */
5949 if (TREE_ASM_WRITTEN (block))
5951 tree new_block = copy_node (block);
5954 origin = (BLOCK_FRAGMENT_ORIGIN (block)
5955 ? BLOCK_FRAGMENT_ORIGIN (block)
5957 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
5958 BLOCK_FRAGMENT_CHAIN (new_block)
5959 = BLOCK_FRAGMENT_CHAIN (origin);
5960 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
5962 NOTE_BLOCK (insn) = new_block;
5966 BLOCK_SUBBLOCKS (block) = 0;
5967 TREE_ASM_WRITTEN (block) = 1;
5968 BLOCK_SUPERCONTEXT (block) = current_block;
5969 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5970 BLOCK_SUBBLOCKS (current_block) = block;
5971 current_block = block;
5972 VARRAY_PUSH_TREE (*p_block_stack, block);
5974 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5976 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
5977 VARRAY_POP (*p_block_stack);
5978 BLOCK_SUBBLOCKS (current_block)
5979 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5980 current_block = BLOCK_SUPERCONTEXT (current_block);
5983 else if (GET_CODE (insn) == CALL_INSN
5984 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5986 rtx cp = PATTERN (insn);
5987 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
5989 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
5991 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
5996 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
5997 appears in the block tree, select one of the fragments to become
5998 the new origin block. */
6001 reorder_fix_fragments (block)
6006 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
6007 tree new_origin = NULL_TREE;
6011 if (! TREE_ASM_WRITTEN (dup_origin))
6013 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
6015 /* Find the first of the remaining fragments. There must
6016 be at least one -- the current block. */
6017 while (! TREE_ASM_WRITTEN (new_origin))
6018 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
6019 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
6022 else if (! dup_origin)
6025 /* Re-root the rest of the fragments to the new origin. In the
6026 case that DUP_ORIGIN was null, that means BLOCK was the origin
6027 of a chain of fragments and we want to remove those fragments
6028 that didn't make it to the output. */
6031 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
6036 if (TREE_ASM_WRITTEN (chain))
6038 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
6040 pp = &BLOCK_FRAGMENT_CHAIN (chain);
6042 chain = BLOCK_FRAGMENT_CHAIN (chain);
6047 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
6048 block = BLOCK_CHAIN (block);
6052 /* Reverse the order of elements in the chain T of blocks,
6053 and return the new head of the chain (old last element). */
6059 tree prev = 0, decl, next;
6060 for (decl = t; decl; decl = next)
6062 next = BLOCK_CHAIN (decl);
6063 BLOCK_CHAIN (decl) = prev;
6069 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6070 non-NULL, list them all into VECTOR, in a depth-first preorder
6071 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6075 all_blocks (block, vector)
6083 TREE_ASM_WRITTEN (block) = 0;
6085 /* Record this block. */
6087 vector[n_blocks] = block;
6091 /* Record the subblocks, and their subblocks... */
6092 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6093 vector ? vector + n_blocks : 0);
6094 block = BLOCK_CHAIN (block);
6100 /* Return a vector containing all the blocks rooted at BLOCK. The
6101 number of elements in the vector is stored in N_BLOCKS_P. The
6102 vector is dynamically allocated; it is the caller's responsibility
6103 to call `free' on the pointer returned. */
6106 get_block_vector (block, n_blocks_p)
6112 *n_blocks_p = all_blocks (block, NULL);
6113 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
6114 all_blocks (block, block_vector);
6116 return block_vector;
6119 static GTY(()) int next_block_index = 2;
6121 /* Set BLOCK_NUMBER for all the blocks in FN. */
6131 /* For SDB and XCOFF debugging output, we start numbering the blocks
6132 from 1 within each function, rather than keeping a running
6134 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6135 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6136 next_block_index = 1;
6139 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6141 /* The top-level BLOCK isn't numbered at all. */
6142 for (i = 1; i < n_blocks; ++i)
6143 /* We number the blocks from two. */
6144 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6146 free (block_vector);
6151 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6154 debug_find_var_in_block_tree (var, block)
6160 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6164 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6166 tree ret = debug_find_var_in_block_tree (var, t);
6174 /* Allocate a function structure and reset its contents to the defaults. */
6177 prepare_function_start ()
6179 cfun = (struct function *) ggc_alloc_cleared (sizeof (struct function));
6181 init_stmt_for_function ();
6182 init_eh_for_function ();
6184 cse_not_expected = ! optimize;
6186 /* Caller save not needed yet. */
6187 caller_save_needed = 0;
6189 /* No stack slots have been made yet. */
6190 stack_slot_list = 0;
6192 current_function_has_nonlocal_label = 0;
6193 current_function_has_nonlocal_goto = 0;
6195 /* There is no stack slot for handling nonlocal gotos. */
6196 nonlocal_goto_handler_slots = 0;
6197 nonlocal_goto_stack_level = 0;
6199 /* No labels have been declared for nonlocal use. */
6200 nonlocal_labels = 0;
6201 nonlocal_goto_handler_labels = 0;
6203 /* No function calls so far in this function. */
6204 function_call_count = 0;
6206 /* No parm regs have been allocated.
6207 (This is important for output_inline_function.) */
6208 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6210 /* Initialize the RTL mechanism. */
6213 /* Initialize the queue of pending postincrement and postdecrements,
6214 and some other info in expr.c. */
6217 /* We haven't done register allocation yet. */
6220 init_varasm_status (cfun);
6222 /* Clear out data used for inlining. */
6223 cfun->inlinable = 0;
6224 cfun->original_decl_initial = 0;
6225 cfun->original_arg_vector = 0;
6227 cfun->stack_alignment_needed = STACK_BOUNDARY;
6228 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6230 /* Set if a call to setjmp is seen. */
6231 current_function_calls_setjmp = 0;
6233 /* Set if a call to longjmp is seen. */
6234 current_function_calls_longjmp = 0;
6236 current_function_calls_alloca = 0;
6237 current_function_calls_eh_return = 0;
6238 current_function_calls_constant_p = 0;
6239 current_function_contains_functions = 0;
6240 current_function_is_leaf = 0;
6241 current_function_nothrow = 0;
6242 current_function_sp_is_unchanging = 0;
6243 current_function_uses_only_leaf_regs = 0;
6244 current_function_has_computed_jump = 0;
6245 current_function_is_thunk = 0;
6247 current_function_returns_pcc_struct = 0;
6248 current_function_returns_struct = 0;
6249 current_function_epilogue_delay_list = 0;
6250 current_function_uses_const_pool = 0;
6251 current_function_uses_pic_offset_table = 0;
6252 current_function_cannot_inline = 0;
6254 /* We have not yet needed to make a label to jump to for tail-recursion. */
6255 tail_recursion_label = 0;
6257 /* We haven't had a need to make a save area for ap yet. */
6258 arg_pointer_save_area = 0;
6260 /* No stack slots allocated yet. */
6263 /* No SAVE_EXPRs in this function yet. */
6266 /* No RTL_EXPRs in this function yet. */
6269 /* Set up to allocate temporaries. */
6272 /* Indicate that we need to distinguish between the return value of the
6273 present function and the return value of a function being called. */
6274 rtx_equal_function_value_matters = 1;
6276 /* Indicate that we have not instantiated virtual registers yet. */
6277 virtuals_instantiated = 0;
6279 /* Indicate that we want CONCATs now. */
6280 generating_concat_p = 1;
6282 /* Indicate we have no need of a frame pointer yet. */
6283 frame_pointer_needed = 0;
6285 /* By default assume not stdarg. */
6286 current_function_stdarg = 0;
6288 /* We haven't made any trampolines for this function yet. */
6289 trampoline_list = 0;
6291 init_pending_stack_adjust ();
6292 inhibit_defer_pop = 0;
6294 current_function_outgoing_args_size = 0;
6296 current_function_funcdef_no = funcdef_no++;
6298 cfun->arc_profile = profile_arc_flag || flag_test_coverage;
6300 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
6302 cfun->max_jumptable_ents = 0;
6304 (*lang_hooks.function.init) (cfun);
6305 if (init_machine_status)
6306 cfun->machine = (*init_machine_status) ();
6309 /* Initialize the rtl expansion mechanism so that we can do simple things
6310 like generate sequences. This is used to provide a context during global
6311 initialization of some passes. */
6313 init_dummy_function_start ()
6315 prepare_function_start ();
6318 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6319 and initialize static variables for generating RTL for the statements
6323 init_function_start (subr, filename, line)
6325 const char *filename;
6328 prepare_function_start ();
6330 current_function_name = (*lang_hooks.decl_printable_name) (subr, 2);
6333 /* Nonzero if this is a nested function that uses a static chain. */
6335 current_function_needs_context
6336 = (decl_function_context (current_function_decl) != 0
6337 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6339 /* Within function body, compute a type's size as soon it is laid out. */
6340 immediate_size_expand++;
6342 /* Prevent ever trying to delete the first instruction of a function.
6343 Also tell final how to output a linenum before the function prologue.
6344 Note linenums could be missing, e.g. when compiling a Java .class file. */
6346 emit_line_note (filename, line);
6348 /* Make sure first insn is a note even if we don't want linenums.
6349 This makes sure the first insn will never be deleted.
6350 Also, final expects a note to appear there. */
6351 emit_note (NULL, NOTE_INSN_DELETED);
6353 /* Set flags used by final.c. */
6354 if (aggregate_value_p (DECL_RESULT (subr)))
6356 #ifdef PCC_STATIC_STRUCT_RETURN
6357 current_function_returns_pcc_struct = 1;
6359 current_function_returns_struct = 1;
6362 /* Warn if this value is an aggregate type,
6363 regardless of which calling convention we are using for it. */
6364 if (warn_aggregate_return
6365 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6366 warning ("function returns an aggregate");
6368 current_function_returns_pointer
6369 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
6372 /* Make sure all values used by the optimization passes have sane
6375 init_function_for_compilation ()
6379 /* No prologue/epilogue insns yet. */
6380 VARRAY_GROW (prologue, 0);
6381 VARRAY_GROW (epilogue, 0);
6382 VARRAY_GROW (sibcall_epilogue, 0);
6385 /* Expand a call to __main at the beginning of a possible main function. */
6387 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6388 #undef HAS_INIT_SECTION
6389 #define HAS_INIT_SECTION
6393 expand_main_function ()
6395 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6396 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6398 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6402 /* Forcibly align the stack. */
6403 #ifdef STACK_GROWS_DOWNWARD
6404 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6405 stack_pointer_rtx, 1, OPTAB_WIDEN);
6407 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6408 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6409 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6410 stack_pointer_rtx, 1, OPTAB_WIDEN);
6412 if (tmp != stack_pointer_rtx)
6413 emit_move_insn (stack_pointer_rtx, tmp);
6415 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6416 tmp = force_reg (Pmode, const0_rtx);
6417 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6421 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6422 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6425 emit_insn_before (seq, tmp);
6431 #ifndef HAS_INIT_SECTION
6432 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), LCT_NORMAL,
6437 /* The PENDING_SIZES represent the sizes of variable-sized types.
6438 Create RTL for the various sizes now (using temporary variables),
6439 so that we can refer to the sizes from the RTL we are generating
6440 for the current function. The PENDING_SIZES are a TREE_LIST. The
6441 TREE_VALUE of each node is a SAVE_EXPR. */
6444 expand_pending_sizes (pending_sizes)
6449 /* Evaluate now the sizes of any types declared among the arguments. */
6450 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6452 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6453 /* Flush the queue in case this parameter declaration has
6459 /* Start the RTL for a new function, and set variables used for
6461 SUBR is the FUNCTION_DECL node.
6462 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6463 the function's parameters, which must be run at any return statement. */
6466 expand_function_start (subr, parms_have_cleanups)
6468 int parms_have_cleanups;
6471 rtx last_ptr = NULL_RTX;
6473 /* Make sure volatile mem refs aren't considered
6474 valid operands of arithmetic insns. */
6475 init_recog_no_volatile ();
6477 current_function_instrument_entry_exit
6478 = (flag_instrument_function_entry_exit
6479 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6481 current_function_profile
6483 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6485 current_function_limit_stack
6486 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6488 /* If function gets a static chain arg, store it in the stack frame.
6489 Do this first, so it gets the first stack slot offset. */
6490 if (current_function_needs_context)
6492 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6494 /* Delay copying static chain if it is not a register to avoid
6495 conflicts with regs used for parameters. */
6496 if (! SMALL_REGISTER_CLASSES
6497 || GET_CODE (static_chain_incoming_rtx) == REG)
6498 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6501 /* If the parameters of this function need cleaning up, get a label
6502 for the beginning of the code which executes those cleanups. This must
6503 be done before doing anything with return_label. */
6504 if (parms_have_cleanups)
6505 cleanup_label = gen_label_rtx ();
6509 /* Make the label for return statements to jump to. Do not special
6510 case machines with special return instructions -- they will be
6511 handled later during jump, ifcvt, or epilogue creation. */
6512 return_label = gen_label_rtx ();
6514 /* Initialize rtx used to return the value. */
6515 /* Do this before assign_parms so that we copy the struct value address
6516 before any library calls that assign parms might generate. */
6518 /* Decide whether to return the value in memory or in a register. */
6519 if (aggregate_value_p (DECL_RESULT (subr)))
6521 /* Returning something that won't go in a register. */
6522 rtx value_address = 0;
6524 #ifdef PCC_STATIC_STRUCT_RETURN
6525 if (current_function_returns_pcc_struct)
6527 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6528 value_address = assemble_static_space (size);
6533 /* Expect to be passed the address of a place to store the value.
6534 If it is passed as an argument, assign_parms will take care of
6536 if (struct_value_incoming_rtx)
6538 value_address = gen_reg_rtx (Pmode);
6539 emit_move_insn (value_address, struct_value_incoming_rtx);
6544 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6545 set_mem_attributes (x, DECL_RESULT (subr), 1);
6546 SET_DECL_RTL (DECL_RESULT (subr), x);
6549 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6550 /* If return mode is void, this decl rtl should not be used. */
6551 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6554 /* Compute the return values into a pseudo reg, which we will copy
6555 into the true return register after the cleanups are done. */
6557 /* In order to figure out what mode to use for the pseudo, we
6558 figure out what the mode of the eventual return register will
6559 actually be, and use that. */
6561 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6564 /* Structures that are returned in registers are not aggregate_value_p,
6565 so we may see a PARALLEL or a REG. */
6566 if (REG_P (hard_reg))
6567 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6568 else if (GET_CODE (hard_reg) == PARALLEL)
6569 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
6573 /* Set DECL_REGISTER flag so that expand_function_end will copy the
6574 result to the real return register(s). */
6575 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6578 /* Initialize rtx for parameters and local variables.
6579 In some cases this requires emitting insns. */
6581 assign_parms (subr);
6583 /* Copy the static chain now if it wasn't a register. The delay is to
6584 avoid conflicts with the parameter passing registers. */
6586 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6587 if (GET_CODE (static_chain_incoming_rtx) != REG)
6588 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6590 /* The following was moved from init_function_start.
6591 The move is supposed to make sdb output more accurate. */
6592 /* Indicate the beginning of the function body,
6593 as opposed to parm setup. */
6594 emit_note (NULL, NOTE_INSN_FUNCTION_BEG);
6596 if (GET_CODE (get_last_insn ()) != NOTE)
6597 emit_note (NULL, NOTE_INSN_DELETED);
6598 parm_birth_insn = get_last_insn ();
6600 context_display = 0;
6601 if (current_function_needs_context)
6603 /* Fetch static chain values for containing functions. */
6604 tem = decl_function_context (current_function_decl);
6605 /* Copy the static chain pointer into a pseudo. If we have
6606 small register classes, copy the value from memory if
6607 static_chain_incoming_rtx is a REG. */
6610 /* If the static chain originally came in a register, put it back
6611 there, then move it out in the next insn. The reason for
6612 this peculiar code is to satisfy function integration. */
6613 if (SMALL_REGISTER_CLASSES
6614 && GET_CODE (static_chain_incoming_rtx) == REG)
6615 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6616 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6621 tree rtlexp = make_node (RTL_EXPR);
6623 RTL_EXPR_RTL (rtlexp) = last_ptr;
6624 context_display = tree_cons (tem, rtlexp, context_display);
6625 tem = decl_function_context (tem);
6628 /* Chain thru stack frames, assuming pointer to next lexical frame
6629 is found at the place we always store it. */
6630 #ifdef FRAME_GROWS_DOWNWARD
6631 last_ptr = plus_constant (last_ptr,
6632 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6634 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6635 set_mem_alias_set (last_ptr, get_frame_alias_set ());
6636 last_ptr = copy_to_reg (last_ptr);
6638 /* If we are not optimizing, ensure that we know that this
6639 piece of context is live over the entire function. */
6641 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6646 if (current_function_instrument_entry_exit)
6648 rtx fun = DECL_RTL (current_function_decl);
6649 if (GET_CODE (fun) == MEM)
6650 fun = XEXP (fun, 0);
6653 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode,
6655 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6657 hard_frame_pointer_rtx),
6661 if (current_function_profile)
6664 PROFILE_HOOK (current_function_funcdef_no);
6668 /* After the display initializations is where the tail-recursion label
6669 should go, if we end up needing one. Ensure we have a NOTE here
6670 since some things (like trampolines) get placed before this. */
6671 tail_recursion_reentry = emit_note (NULL, NOTE_INSN_DELETED);
6673 /* Evaluate now the sizes of any types declared among the arguments. */
6674 expand_pending_sizes (nreverse (get_pending_sizes ()));
6676 /* Make sure there is a line number after the function entry setup code. */
6677 force_next_line_note ();
6680 /* Undo the effects of init_dummy_function_start. */
6682 expand_dummy_function_end ()
6684 /* End any sequences that failed to be closed due to syntax errors. */
6685 while (in_sequence_p ())
6688 /* Outside function body, can't compute type's actual size
6689 until next function's body starts. */
6691 free_after_parsing (cfun);
6692 free_after_compilation (cfun);
6696 /* Call DOIT for each hard register used as a return value from
6697 the current function. */
6700 diddle_return_value (doit, arg)
6701 void (*doit) PARAMS ((rtx, void *));
6704 rtx outgoing = current_function_return_rtx;
6709 if (GET_CODE (outgoing) == REG)
6710 (*doit) (outgoing, arg);
6711 else if (GET_CODE (outgoing) == PARALLEL)
6715 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6717 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6719 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6726 do_clobber_return_reg (reg, arg)
6728 void *arg ATTRIBUTE_UNUSED;
6730 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6734 clobber_return_register ()
6736 diddle_return_value (do_clobber_return_reg, NULL);
6738 /* In case we do use pseudo to return value, clobber it too. */
6739 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6741 tree decl_result = DECL_RESULT (current_function_decl);
6742 rtx decl_rtl = DECL_RTL (decl_result);
6743 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6745 do_clobber_return_reg (decl_rtl, NULL);
6751 do_use_return_reg (reg, arg)
6753 void *arg ATTRIBUTE_UNUSED;
6755 emit_insn (gen_rtx_USE (VOIDmode, reg));
6759 use_return_register ()
6761 diddle_return_value (do_use_return_reg, NULL);
6764 static GTY(()) rtx initial_trampoline;
6766 /* Generate RTL for the end of the current function.
6767 FILENAME and LINE are the current position in the source file.
6769 It is up to language-specific callers to do cleanups for parameters--
6770 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6773 expand_function_end (filename, line, end_bindings)
6774 const char *filename;
6781 finish_expr_for_function ();
6783 /* If arg_pointer_save_area was referenced only from a nested
6784 function, we will not have initialized it yet. Do that now. */
6785 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6786 get_arg_pointer_save_area (cfun);
6788 #ifdef NON_SAVING_SETJMP
6789 /* Don't put any variables in registers if we call setjmp
6790 on a machine that fails to restore the registers. */
6791 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6793 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6794 setjmp_protect (DECL_INITIAL (current_function_decl));
6796 setjmp_protect_args ();
6800 /* Initialize any trampolines required by this function. */
6801 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6803 tree function = TREE_PURPOSE (link);
6804 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6805 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6806 #ifdef TRAMPOLINE_TEMPLATE
6811 #ifdef TRAMPOLINE_TEMPLATE
6812 /* First make sure this compilation has a template for
6813 initializing trampolines. */
6814 if (initial_trampoline == 0)
6817 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6818 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
6822 /* Generate insns to initialize the trampoline. */
6824 tramp = round_trampoline_addr (XEXP (tramp, 0));
6825 #ifdef TRAMPOLINE_TEMPLATE
6826 blktramp = replace_equiv_address (initial_trampoline, tramp);
6827 emit_block_move (blktramp, initial_trampoline,
6828 GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL);
6830 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6834 /* Put those insns at entry to the containing function (this one). */
6835 emit_insn_before (seq, tail_recursion_reentry);
6838 /* If we are doing stack checking and this function makes calls,
6839 do a stack probe at the start of the function to ensure we have enough
6840 space for another stack frame. */
6841 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6845 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6846 if (GET_CODE (insn) == CALL_INSN)
6849 probe_stack_range (STACK_CHECK_PROTECT,
6850 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6853 emit_insn_before (seq, tail_recursion_reentry);
6858 /* Warn about unused parms if extra warnings were specified. */
6859 /* Either ``-Wextra -Wunused'' or ``-Wunused-parameter'' enables this
6860 warning. WARN_UNUSED_PARAMETER is negative when set by
6861 -Wunused. Note that -Wall implies -Wunused, so ``-Wall -Wextra'' will
6862 also give these warnings. */
6863 if (warn_unused_parameter > 0
6864 || (warn_unused_parameter < 0 && extra_warnings))
6868 for (decl = DECL_ARGUMENTS (current_function_decl);
6869 decl; decl = TREE_CHAIN (decl))
6870 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6871 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6872 warning_with_decl (decl, "unused parameter `%s'");
6875 /* Delete handlers for nonlocal gotos if nothing uses them. */
6876 if (nonlocal_goto_handler_slots != 0
6877 && ! current_function_has_nonlocal_label)
6880 /* End any sequences that failed to be closed due to syntax errors. */
6881 while (in_sequence_p ())
6884 /* Outside function body, can't compute type's actual size
6885 until next function's body starts. */
6886 immediate_size_expand--;
6888 clear_pending_stack_adjust ();
6889 do_pending_stack_adjust ();
6891 /* Mark the end of the function body.
6892 If control reaches this insn, the function can drop through
6893 without returning a value. */
6894 emit_note (NULL, NOTE_INSN_FUNCTION_END);
6896 /* Must mark the last line number note in the function, so that the test
6897 coverage code can avoid counting the last line twice. This just tells
6898 the code to ignore the immediately following line note, since there
6899 already exists a copy of this note somewhere above. This line number
6900 note is still needed for debugging though, so we can't delete it. */
6901 if (flag_test_coverage)
6902 emit_note (NULL, NOTE_INSN_REPEATED_LINE_NUMBER);
6904 /* Output a linenumber for the end of the function.
6905 SDB depends on this. */
6906 emit_line_note_force (filename, line);
6908 /* Before the return label (if any), clobber the return
6909 registers so that they are not propagated live to the rest of
6910 the function. This can only happen with functions that drop
6911 through; if there had been a return statement, there would
6912 have either been a return rtx, or a jump to the return label.
6914 We delay actual code generation after the current_function_value_rtx
6916 clobber_after = get_last_insn ();
6918 /* Output the label for the actual return from the function,
6919 if one is expected. This happens either because a function epilogue
6920 is used instead of a return instruction, or because a return was done
6921 with a goto in order to run local cleanups, or because of pcc-style
6922 structure returning. */
6924 emit_label (return_label);
6926 /* C++ uses this. */
6928 expand_end_bindings (0, 0, 0);
6930 if (current_function_instrument_entry_exit)
6932 rtx fun = DECL_RTL (current_function_decl);
6933 if (GET_CODE (fun) == MEM)
6934 fun = XEXP (fun, 0);
6937 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode,
6939 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6941 hard_frame_pointer_rtx),
6945 /* Let except.c know where it should emit the call to unregister
6946 the function context for sjlj exceptions. */
6947 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
6948 sjlj_emit_function_exit_after (get_last_insn ());
6950 /* If we had calls to alloca, and this machine needs
6951 an accurate stack pointer to exit the function,
6952 insert some code to save and restore the stack pointer. */
6953 #ifdef EXIT_IGNORE_STACK
6954 if (! EXIT_IGNORE_STACK)
6956 if (current_function_calls_alloca)
6960 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6961 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6964 /* If scalar return value was computed in a pseudo-reg, or was a named
6965 return value that got dumped to the stack, copy that to the hard
6967 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6969 tree decl_result = DECL_RESULT (current_function_decl);
6970 rtx decl_rtl = DECL_RTL (decl_result);
6972 if (REG_P (decl_rtl)
6973 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
6974 : DECL_REGISTER (decl_result))
6976 rtx real_decl_rtl = current_function_return_rtx;
6978 /* This should be set in assign_parms. */
6979 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
6982 /* If this is a BLKmode structure being returned in registers,
6983 then use the mode computed in expand_return. Note that if
6984 decl_rtl is memory, then its mode may have been changed,
6985 but that current_function_return_rtx has not. */
6986 if (GET_MODE (real_decl_rtl) == BLKmode)
6987 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
6989 /* If a named return value dumped decl_return to memory, then
6990 we may need to re-do the PROMOTE_MODE signed/unsigned
6992 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
6994 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
6996 #ifdef PROMOTE_FUNCTION_RETURN
6997 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
7001 convert_move (real_decl_rtl, decl_rtl, unsignedp);
7003 else if (GET_CODE (real_decl_rtl) == PARALLEL)
7005 /* If expand_function_start has created a PARALLEL for decl_rtl,
7006 move the result to the real return registers. Otherwise, do
7007 a group load from decl_rtl for a named return. */
7008 if (GET_CODE (decl_rtl) == PARALLEL)
7009 emit_group_move (real_decl_rtl, decl_rtl);
7011 emit_group_load (real_decl_rtl, decl_rtl,
7012 int_size_in_bytes (TREE_TYPE (decl_result)));
7015 emit_move_insn (real_decl_rtl, decl_rtl);
7019 /* If returning a structure, arrange to return the address of the value
7020 in a place where debuggers expect to find it.
7022 If returning a structure PCC style,
7023 the caller also depends on this value.
7024 And current_function_returns_pcc_struct is not necessarily set. */
7025 if (current_function_returns_struct
7026 || current_function_returns_pcc_struct)
7029 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
7030 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
7031 #ifdef FUNCTION_OUTGOING_VALUE
7033 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
7034 current_function_decl);
7037 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
7040 /* Mark this as a function return value so integrate will delete the
7041 assignment and USE below when inlining this function. */
7042 REG_FUNCTION_VALUE_P (outgoing) = 1;
7044 #ifdef POINTERS_EXTEND_UNSIGNED
7045 /* The address may be ptr_mode and OUTGOING may be Pmode. */
7046 if (GET_MODE (outgoing) != GET_MODE (value_address))
7047 value_address = convert_memory_address (GET_MODE (outgoing),
7051 emit_move_insn (outgoing, value_address);
7053 /* Show return register used to hold result (in this case the address
7055 current_function_return_rtx = outgoing;
7058 /* If this is an implementation of throw, do what's necessary to
7059 communicate between __builtin_eh_return and the epilogue. */
7060 expand_eh_return ();
7062 /* Emit the actual code to clobber return register. */
7067 clobber_return_register ();
7071 after = emit_insn_after (seq, clobber_after);
7073 if (clobber_after != after)
7074 cfun->x_clobber_return_insn = after;
7077 /* ??? This should no longer be necessary since stupid is no longer with
7078 us, but there are some parts of the compiler (eg reload_combine, and
7079 sh mach_dep_reorg) that still try and compute their own lifetime info
7080 instead of using the general framework. */
7081 use_return_register ();
7083 /* Fix up any gotos that jumped out to the outermost
7084 binding level of the function.
7085 Must follow emitting RETURN_LABEL. */
7087 /* If you have any cleanups to do at this point,
7088 and they need to create temporary variables,
7089 then you will lose. */
7090 expand_fixups (get_insns ());
7094 get_arg_pointer_save_area (f)
7097 rtx ret = f->x_arg_pointer_save_area;
7101 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
7102 f->x_arg_pointer_save_area = ret;
7105 if (f == cfun && ! f->arg_pointer_save_area_init)
7109 /* Save the arg pointer at the beginning of the function. The
7110 generated stack slot may not be a valid memory address, so we
7111 have to check it and fix it if necessary. */
7113 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
7117 push_topmost_sequence ();
7118 emit_insn_after (seq, get_insns ());
7119 pop_topmost_sequence ();
7125 /* Extend a vector that records the INSN_UIDs of INSNS
7126 (a list of one or more insns). */
7129 record_insns (insns, vecp)
7138 while (tmp != NULL_RTX)
7141 tmp = NEXT_INSN (tmp);
7144 i = VARRAY_SIZE (*vecp);
7145 VARRAY_GROW (*vecp, i + len);
7147 while (tmp != NULL_RTX)
7149 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
7151 tmp = NEXT_INSN (tmp);
7155 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
7156 be running after reorg, SEQUENCE rtl is possible. */
7159 contains (insn, vec)
7165 if (GET_CODE (insn) == INSN
7166 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7169 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7170 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7171 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7177 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7178 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7185 prologue_epilogue_contains (insn)
7188 if (contains (insn, prologue))
7190 if (contains (insn, epilogue))
7196 sibcall_epilogue_contains (insn)
7199 if (sibcall_epilogue)
7200 return contains (insn, sibcall_epilogue);
7205 /* Insert gen_return at the end of block BB. This also means updating
7206 block_for_insn appropriately. */
7209 emit_return_into_block (bb, line_note)
7213 emit_jump_insn_after (gen_return (), bb->end);
7215 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
7216 NOTE_LINE_NUMBER (line_note), PREV_INSN (bb->end));
7218 #endif /* HAVE_return */
7220 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7222 /* These functions convert the epilogue into a variant that does not modify the
7223 stack pointer. This is used in cases where a function returns an object
7224 whose size is not known until it is computed. The called function leaves the
7225 object on the stack, leaves the stack depressed, and returns a pointer to
7228 What we need to do is track all modifications and references to the stack
7229 pointer, deleting the modifications and changing the references to point to
7230 the location the stack pointer would have pointed to had the modifications
7233 These functions need to be portable so we need to make as few assumptions
7234 about the epilogue as we can. However, the epilogue basically contains
7235 three things: instructions to reset the stack pointer, instructions to
7236 reload registers, possibly including the frame pointer, and an
7237 instruction to return to the caller.
7239 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7240 We also make no attempt to validate the insns we make since if they are
7241 invalid, we probably can't do anything valid. The intent is that these
7242 routines get "smarter" as more and more machines start to use them and
7243 they try operating on different epilogues.
7245 We use the following structure to track what the part of the epilogue that
7246 we've already processed has done. We keep two copies of the SP equivalence,
7247 one for use during the insn we are processing and one for use in the next
7248 insn. The difference is because one part of a PARALLEL may adjust SP
7249 and the other may use it. */
7253 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7254 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7255 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7256 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7257 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7258 should be set to once we no longer need
7262 static void handle_epilogue_set PARAMS ((rtx, struct epi_info *));
7263 static void emit_equiv_load PARAMS ((struct epi_info *));
7265 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
7266 no modifications to the stack pointer. Return the new list of insns. */
7269 keep_stack_depressed (insns)
7273 struct epi_info info;
7276 /* If the epilogue is just a single instruction, it ust be OK as is. */
7278 if (NEXT_INSN (insns) == NULL_RTX)
7281 /* Otherwise, start a sequence, initialize the information we have, and
7282 process all the insns we were given. */
7285 info.sp_equiv_reg = stack_pointer_rtx;
7287 info.equiv_reg_src = 0;
7291 while (insn != NULL_RTX)
7293 next = NEXT_INSN (insn);
7302 /* If this insn references the register that SP is equivalent to and
7303 we have a pending load to that register, we must force out the load
7304 first and then indicate we no longer know what SP's equivalent is. */
7305 if (info.equiv_reg_src != 0
7306 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7308 emit_equiv_load (&info);
7309 info.sp_equiv_reg = 0;
7312 info.new_sp_equiv_reg = info.sp_equiv_reg;
7313 info.new_sp_offset = info.sp_offset;
7315 /* If this is a (RETURN) and the return address is on the stack,
7316 update the address and change to an indirect jump. */
7317 if (GET_CODE (PATTERN (insn)) == RETURN
7318 || (GET_CODE (PATTERN (insn)) == PARALLEL
7319 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7321 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7323 HOST_WIDE_INT offset = 0;
7324 rtx jump_insn, jump_set;
7326 /* If the return address is in a register, we can emit the insn
7327 unchanged. Otherwise, it must be a MEM and we see what the
7328 base register and offset are. In any case, we have to emit any
7329 pending load to the equivalent reg of SP, if any. */
7330 if (GET_CODE (retaddr) == REG)
7332 emit_equiv_load (&info);
7337 else if (GET_CODE (retaddr) == MEM
7338 && GET_CODE (XEXP (retaddr, 0)) == REG)
7339 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7340 else if (GET_CODE (retaddr) == MEM
7341 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7342 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7343 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7345 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7346 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7351 /* If the base of the location containing the return pointer
7352 is SP, we must update it with the replacement address. Otherwise,
7353 just build the necessary MEM. */
7354 retaddr = plus_constant (base, offset);
7355 if (base == stack_pointer_rtx)
7356 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7357 plus_constant (info.sp_equiv_reg,
7360 retaddr = gen_rtx_MEM (Pmode, retaddr);
7362 /* If there is a pending load to the equivalent register for SP
7363 and we reference that register, we must load our address into
7364 a scratch register and then do that load. */
7365 if (info.equiv_reg_src
7366 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7371 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7372 if (HARD_REGNO_MODE_OK (regno, Pmode)
7373 && !fixed_regs[regno]
7374 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7375 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7377 && !refers_to_regno_p (regno,
7378 regno + HARD_REGNO_NREGS (regno,
7380 info.equiv_reg_src, NULL))
7383 if (regno == FIRST_PSEUDO_REGISTER)
7386 reg = gen_rtx_REG (Pmode, regno);
7387 emit_move_insn (reg, retaddr);
7391 emit_equiv_load (&info);
7392 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7394 /* Show the SET in the above insn is a RETURN. */
7395 jump_set = single_set (jump_insn);
7399 SET_IS_RETURN_P (jump_set) = 1;
7402 /* If SP is not mentioned in the pattern and its equivalent register, if
7403 any, is not modified, just emit it. Otherwise, if neither is set,
7404 replace the reference to SP and emit the insn. If none of those are
7405 true, handle each SET individually. */
7406 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7407 && (info.sp_equiv_reg == stack_pointer_rtx
7408 || !reg_set_p (info.sp_equiv_reg, insn)))
7410 else if (! reg_set_p (stack_pointer_rtx, insn)
7411 && (info.sp_equiv_reg == stack_pointer_rtx
7412 || !reg_set_p (info.sp_equiv_reg, insn)))
7414 if (! validate_replace_rtx (stack_pointer_rtx,
7415 plus_constant (info.sp_equiv_reg,
7422 else if (GET_CODE (PATTERN (insn)) == SET)
7423 handle_epilogue_set (PATTERN (insn), &info);
7424 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7426 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7427 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7428 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7433 info.sp_equiv_reg = info.new_sp_equiv_reg;
7434 info.sp_offset = info.new_sp_offset;
7439 insns = get_insns ();
7444 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7445 structure that contains information about what we've seen so far. We
7446 process this SET by either updating that data or by emitting one or
7450 handle_epilogue_set (set, p)
7454 /* First handle the case where we are setting SP. Record what it is being
7455 set from. If unknown, abort. */
7456 if (reg_set_p (stack_pointer_rtx, set))
7458 if (SET_DEST (set) != stack_pointer_rtx)
7461 if (GET_CODE (SET_SRC (set)) == PLUS
7462 && GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7464 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7465 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7468 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7470 /* If we are adjusting SP, we adjust from the old data. */
7471 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7473 p->new_sp_equiv_reg = p->sp_equiv_reg;
7474 p->new_sp_offset += p->sp_offset;
7477 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7483 /* Next handle the case where we are setting SP's equivalent register.
7484 If we already have a value to set it to, abort. We could update, but
7485 there seems little point in handling that case. Note that we have
7486 to allow for the case where we are setting the register set in
7487 the previous part of a PARALLEL inside a single insn. But use the
7488 old offset for any updates within this insn. */
7489 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7491 if (!rtx_equal_p (p->new_sp_equiv_reg, SET_DEST (set))
7492 || p->equiv_reg_src != 0)
7496 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7497 plus_constant (p->sp_equiv_reg,
7501 /* Otherwise, replace any references to SP in the insn to its new value
7502 and emit the insn. */
7505 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7506 plus_constant (p->sp_equiv_reg,
7508 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7509 plus_constant (p->sp_equiv_reg,
7515 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7521 if (p->equiv_reg_src != 0)
7522 emit_move_insn (p->sp_equiv_reg, p->equiv_reg_src);
7524 p->equiv_reg_src = 0;
7528 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7529 this into place with notes indicating where the prologue ends and where
7530 the epilogue begins. Update the basic block information when possible. */
7533 thread_prologue_and_epilogue_insns (f)
7534 rtx f ATTRIBUTE_UNUSED;
7538 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7541 #ifdef HAVE_prologue
7542 rtx prologue_end = NULL_RTX;
7544 #if defined (HAVE_epilogue) || defined(HAVE_return)
7545 rtx epilogue_end = NULL_RTX;
7548 #ifdef HAVE_prologue
7552 seq = gen_prologue ();
7555 /* Retain a map of the prologue insns. */
7556 record_insns (seq, &prologue);
7557 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
7562 /* Can't deal with multiple successors of the entry block
7563 at the moment. Function should always have at least one
7565 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7568 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7573 /* If the exit block has no non-fake predecessors, we don't need
7575 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7576 if ((e->flags & EDGE_FAKE) == 0)
7582 if (optimize && HAVE_return)
7584 /* If we're allowed to generate a simple return instruction,
7585 then by definition we don't need a full epilogue. Examine
7586 the block that falls through to EXIT. If it does not
7587 contain any code, examine its predecessors and try to
7588 emit (conditional) return instructions. */
7594 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7595 if (e->flags & EDGE_FALLTHRU)
7601 /* Verify that there are no active instructions in the last block. */
7603 while (label && GET_CODE (label) != CODE_LABEL)
7605 if (active_insn_p (label))
7607 label = PREV_INSN (label);
7610 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7612 rtx epilogue_line_note = NULL_RTX;
7614 /* Locate the line number associated with the closing brace,
7615 if we can find one. */
7616 for (seq = get_last_insn ();
7617 seq && ! active_insn_p (seq);
7618 seq = PREV_INSN (seq))
7619 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7621 epilogue_line_note = seq;
7625 for (e = last->pred; e; e = e_next)
7627 basic_block bb = e->src;
7630 e_next = e->pred_next;
7631 if (bb == ENTRY_BLOCK_PTR)
7635 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7638 /* If we have an unconditional jump, we can replace that
7639 with a simple return instruction. */
7640 if (simplejump_p (jump))
7642 emit_return_into_block (bb, epilogue_line_note);
7646 /* If we have a conditional jump, we can try to replace
7647 that with a conditional return instruction. */
7648 else if (condjump_p (jump))
7650 if (! redirect_jump (jump, 0, 0))
7653 /* If this block has only one successor, it both jumps
7654 and falls through to the fallthru block, so we can't
7656 if (bb->succ->succ_next == NULL)
7662 /* Fix up the CFG for the successful change we just made. */
7663 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7666 /* Emit a return insn for the exit fallthru block. Whether
7667 this is still reachable will be determined later. */
7669 emit_barrier_after (last->end);
7670 emit_return_into_block (last, epilogue_line_note);
7671 epilogue_end = last->end;
7672 last->succ->flags &= ~EDGE_FALLTHRU;
7677 #ifdef HAVE_epilogue
7680 /* Find the edge that falls through to EXIT. Other edges may exist
7681 due to RETURN instructions, but those don't need epilogues.
7682 There really shouldn't be a mixture -- either all should have
7683 been converted or none, however... */
7685 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7686 if (e->flags & EDGE_FALLTHRU)
7692 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
7694 seq = gen_epilogue ();
7696 #ifdef INCOMING_RETURN_ADDR_RTX
7697 /* If this function returns with the stack depressed and we can support
7698 it, massage the epilogue to actually do that. */
7699 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7700 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7701 seq = keep_stack_depressed (seq);
7704 emit_jump_insn (seq);
7706 /* Retain a map of the epilogue insns. */
7707 record_insns (seq, &epilogue);
7712 insert_insn_on_edge (seq, e);
7719 commit_edge_insertions ();
7721 #ifdef HAVE_sibcall_epilogue
7722 /* Emit sibling epilogues before any sibling call sites. */
7723 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7725 basic_block bb = e->src;
7730 if (GET_CODE (insn) != CALL_INSN
7731 || ! SIBLING_CALL_P (insn))
7735 emit_insn (gen_sibcall_epilogue ());
7739 /* Retain a map of the epilogue insns. Used in life analysis to
7740 avoid getting rid of sibcall epilogue insns. Do this before we
7741 actually emit the sequence. */
7742 record_insns (seq, &sibcall_epilogue);
7744 i = PREV_INSN (insn);
7745 newinsn = emit_insn_before (seq, insn);
7749 #ifdef HAVE_prologue
7754 /* GDB handles `break f' by setting a breakpoint on the first
7755 line note after the prologue. Which means (1) that if
7756 there are line number notes before where we inserted the
7757 prologue we should move them, and (2) we should generate a
7758 note before the end of the first basic block, if there isn't
7761 ??? This behavior is completely broken when dealing with
7762 multiple entry functions. We simply place the note always
7763 into first basic block and let alternate entry points
7767 for (insn = prologue_end; insn; insn = prev)
7769 prev = PREV_INSN (insn);
7770 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7772 /* Note that we cannot reorder the first insn in the
7773 chain, since rest_of_compilation relies on that
7774 remaining constant. */
7777 reorder_insns (insn, insn, prologue_end);
7781 /* Find the last line number note in the first block. */
7782 for (insn = ENTRY_BLOCK_PTR->next_bb->end;
7783 insn != prologue_end && insn;
7784 insn = PREV_INSN (insn))
7785 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7788 /* If we didn't find one, make a copy of the first line number
7792 for (insn = next_active_insn (prologue_end);
7794 insn = PREV_INSN (insn))
7795 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7797 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7798 NOTE_LINE_NUMBER (insn),
7805 #ifdef HAVE_epilogue
7810 /* Similarly, move any line notes that appear after the epilogue.
7811 There is no need, however, to be quite so anal about the existence
7813 for (insn = epilogue_end; insn; insn = next)
7815 next = NEXT_INSN (insn);
7816 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7817 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7823 /* Reposition the prologue-end and epilogue-begin notes after instruction
7824 scheduling and delayed branch scheduling. */
7827 reposition_prologue_and_epilogue_notes (f)
7828 rtx f ATTRIBUTE_UNUSED;
7830 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7831 rtx insn, last, note;
7834 if ((len = VARRAY_SIZE (prologue)) > 0)
7838 /* Scan from the beginning until we reach the last prologue insn.
7839 We apparently can't depend on basic_block_{head,end} after
7841 for (insn = f; insn; insn = NEXT_INSN (insn))
7843 if (GET_CODE (insn) == NOTE)
7845 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7848 else if (contains (insn, prologue))
7858 /* Find the prologue-end note if we haven't already, and
7859 move it to just after the last prologue insn. */
7862 for (note = last; (note = NEXT_INSN (note));)
7863 if (GET_CODE (note) == NOTE
7864 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7868 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7869 if (GET_CODE (last) == CODE_LABEL)
7870 last = NEXT_INSN (last);
7871 reorder_insns (note, note, last);
7875 if ((len = VARRAY_SIZE (epilogue)) > 0)
7879 /* Scan from the end until we reach the first epilogue insn.
7880 We apparently can't depend on basic_block_{head,end} after
7882 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
7884 if (GET_CODE (insn) == NOTE)
7886 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7889 else if (contains (insn, epilogue))
7899 /* Find the epilogue-begin note if we haven't already, and
7900 move it to just before the first epilogue insn. */
7903 for (note = insn; (note = PREV_INSN (note));)
7904 if (GET_CODE (note) == NOTE
7905 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7909 if (PREV_INSN (last) != note)
7910 reorder_insns (note, note, PREV_INSN (last));
7913 #endif /* HAVE_prologue or HAVE_epilogue */
7916 /* Called once, at initialization, to initialize function.c. */
7919 init_function_once ()
7921 VARRAY_INT_INIT (prologue, 0, "prologue");
7922 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7923 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
7926 #include "gt-function.h"