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 slot.
1308 This is done when an address-reference to the variable is seen. */
1311 put_var_into_stack (decl)
1315 enum machine_mode promoted_mode, decl_mode;
1316 struct function *function = 0;
1318 int can_use_addressof;
1319 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1320 int usedp = (TREE_USED (decl)
1321 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1323 context = decl_function_context (decl);
1325 /* Get the current rtl used for this object and its original mode. */
1326 reg = (TREE_CODE (decl) == SAVE_EXPR
1327 ? SAVE_EXPR_RTL (decl)
1328 : DECL_RTL_IF_SET (decl));
1330 /* No need to do anything if decl has no rtx yet
1331 since in that case caller is setting TREE_ADDRESSABLE
1332 and a stack slot will be assigned when the rtl is made. */
1336 /* Get the declared mode for this object. */
1337 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1338 : DECL_MODE (decl));
1339 /* Get the mode it's actually stored in. */
1340 promoted_mode = GET_MODE (reg);
1342 /* If this variable comes from an outer function, find that
1343 function's saved context. Don't use find_function_data here,
1344 because it might not be in any active function.
1345 FIXME: Is that really supposed to happen?
1346 It does in ObjC at least. */
1347 if (context != current_function_decl && context != inline_function_decl)
1348 for (function = outer_function_chain; function; function = function->outer)
1349 if (function->decl == context)
1352 /* If this is a variable-size object with a pseudo to address it,
1353 put that pseudo into the stack, if the var is nonlocal. */
1354 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1355 && GET_CODE (reg) == MEM
1356 && GET_CODE (XEXP (reg, 0)) == REG
1357 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1359 reg = XEXP (reg, 0);
1360 decl_mode = promoted_mode = GET_MODE (reg);
1366 /* FIXME make it work for promoted modes too */
1367 && decl_mode == promoted_mode
1368 #ifdef NON_SAVING_SETJMP
1369 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1373 /* If we can't use ADDRESSOF, make sure we see through one we already
1375 if (! can_use_addressof && GET_CODE (reg) == MEM
1376 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1377 reg = XEXP (XEXP (reg, 0), 0);
1379 /* Now we should have a value that resides in one or more pseudo regs. */
1381 if (GET_CODE (reg) == REG)
1383 /* If this variable lives in the current function and we don't need
1384 to put things in the stack for the sake of setjmp, try to keep it
1385 in a register until we know we actually need the address. */
1386 if (can_use_addressof)
1387 gen_mem_addressof (reg, decl);
1389 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1390 decl_mode, volatilep, 0, usedp, 0);
1392 else if (GET_CODE (reg) == CONCAT)
1394 /* A CONCAT contains two pseudos; put them both in the stack.
1395 We do it so they end up consecutive.
1396 We fixup references to the parts only after we fixup references
1397 to the whole CONCAT, lest we do double fixups for the latter
1399 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1400 tree part_type = (*lang_hooks.types.type_for_mode) (part_mode, 0);
1401 rtx lopart = XEXP (reg, 0);
1402 rtx hipart = XEXP (reg, 1);
1403 #ifdef FRAME_GROWS_DOWNWARD
1404 /* Since part 0 should have a lower address, do it second. */
1405 put_reg_into_stack (function, hipart, part_type, part_mode,
1406 part_mode, volatilep, 0, 0, 0);
1407 put_reg_into_stack (function, lopart, part_type, part_mode,
1408 part_mode, volatilep, 0, 0, 0);
1410 put_reg_into_stack (function, lopart, part_type, part_mode,
1411 part_mode, volatilep, 0, 0, 0);
1412 put_reg_into_stack (function, hipart, part_type, part_mode,
1413 part_mode, volatilep, 0, 0, 0);
1416 /* Change the CONCAT into a combined MEM for both parts. */
1417 PUT_CODE (reg, MEM);
1418 MEM_ATTRS (reg) = 0;
1420 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1421 already computed alias sets. Here we want to re-generate. */
1423 SET_DECL_RTL (decl, NULL);
1424 set_mem_attributes (reg, decl, 1);
1426 SET_DECL_RTL (decl, reg);
1428 /* The two parts are in memory order already.
1429 Use the lower parts address as ours. */
1430 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1431 /* Prevent sharing of rtl that might lose. */
1432 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1433 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1436 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1438 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1439 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1446 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1447 into the stack frame of FUNCTION (0 means the current function).
1448 DECL_MODE is the machine mode of the user-level data type.
1449 PROMOTED_MODE is the machine mode of the register.
1450 VOLATILE_P is nonzero if this is for a "volatile" decl.
1451 USED_P is nonzero if this reg might have already been used in an insn. */
1454 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1455 original_regno, used_p, ht)
1456 struct function *function;
1459 enum machine_mode promoted_mode, decl_mode;
1461 unsigned int original_regno;
1465 struct function *func = function ? function : cfun;
1467 unsigned int regno = original_regno;
1470 regno = REGNO (reg);
1472 if (regno < func->x_max_parm_reg)
1473 new = func->x_parm_reg_stack_loc[regno];
1476 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1478 PUT_CODE (reg, MEM);
1479 PUT_MODE (reg, decl_mode);
1480 XEXP (reg, 0) = XEXP (new, 0);
1481 MEM_ATTRS (reg) = 0;
1482 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1483 MEM_VOLATILE_P (reg) = volatile_p;
1485 /* If this is a memory ref that contains aggregate components,
1486 mark it as such for cse and loop optimize. If we are reusing a
1487 previously generated stack slot, then we need to copy the bit in
1488 case it was set for other reasons. For instance, it is set for
1489 __builtin_va_alist. */
1492 MEM_SET_IN_STRUCT_P (reg,
1493 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1494 set_mem_alias_set (reg, get_alias_set (type));
1498 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1501 /* Make sure that all refs to the variable, previously made
1502 when it was a register, are fixed up to be valid again.
1503 See function above for meaning of arguments. */
1506 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht)
1507 struct function *function;
1510 enum machine_mode promoted_mode;
1513 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1517 struct var_refs_queue *temp;
1520 = (struct var_refs_queue *) ggc_alloc (sizeof (struct var_refs_queue));
1521 temp->modified = reg;
1522 temp->promoted_mode = promoted_mode;
1523 temp->unsignedp = unsigned_p;
1524 temp->next = function->fixup_var_refs_queue;
1525 function->fixup_var_refs_queue = temp;
1528 /* Variable is local; fix it up now. */
1529 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht);
1533 fixup_var_refs (var, promoted_mode, unsignedp, may_share, ht)
1535 enum machine_mode promoted_mode;
1541 rtx first_insn = get_insns ();
1542 struct sequence_stack *stack = seq_stack;
1543 tree rtl_exps = rtl_expr_chain;
1545 /* If there's a hash table, it must record all uses of VAR. */
1550 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp,
1555 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1556 stack == 0, may_share);
1558 /* Scan all pending sequences too. */
1559 for (; stack; stack = stack->next)
1561 push_to_full_sequence (stack->first, stack->last);
1562 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1563 stack->next != 0, may_share);
1564 /* Update remembered end of sequence
1565 in case we added an insn at the end. */
1566 stack->last = get_last_insn ();
1570 /* Scan all waiting RTL_EXPRs too. */
1571 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1573 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1574 if (seq != const0_rtx && seq != 0)
1576 push_to_sequence (seq);
1577 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1584 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1585 some part of an insn. Return a struct fixup_replacement whose OLD
1586 value is equal to X. Allocate a new structure if no such entry exists. */
1588 static struct fixup_replacement *
1589 find_fixup_replacement (replacements, x)
1590 struct fixup_replacement **replacements;
1593 struct fixup_replacement *p;
1595 /* See if we have already replaced this. */
1596 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1601 p = (struct fixup_replacement *) xmalloc (sizeof (struct fixup_replacement));
1604 p->next = *replacements;
1611 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1612 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1613 for the current function. MAY_SHARE is either a MEM that is not
1614 to be unshared or a list of them. */
1617 fixup_var_refs_insns (insn, var, promoted_mode, unsignedp, toplevel, may_share)
1620 enum machine_mode promoted_mode;
1627 /* fixup_var_refs_insn might modify insn, so save its next
1629 rtx next = NEXT_INSN (insn);
1631 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1632 the three sequences they (potentially) contain, and process
1633 them recursively. The CALL_INSN itself is not interesting. */
1635 if (GET_CODE (insn) == CALL_INSN
1636 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1640 /* Look at the Normal call, sibling call and tail recursion
1641 sequences attached to the CALL_PLACEHOLDER. */
1642 for (i = 0; i < 3; i++)
1644 rtx seq = XEXP (PATTERN (insn), i);
1647 push_to_sequence (seq);
1648 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1650 XEXP (PATTERN (insn), i) = get_insns ();
1656 else if (INSN_P (insn))
1657 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel,
1664 /* Look up the insns which reference VAR in HT and fix them up. Other
1665 arguments are the same as fixup_var_refs_insns.
1667 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1668 because the hash table will point straight to the interesting insn
1669 (inside the CALL_PLACEHOLDER). */
1672 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp, may_share)
1675 enum machine_mode promoted_mode;
1679 struct insns_for_mem_entry tmp;
1680 struct insns_for_mem_entry *ime;
1684 ime = (struct insns_for_mem_entry *) htab_find (ht, &tmp);
1685 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1))
1686 if (INSN_P (XEXP (insn_list, 0)))
1687 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode,
1688 unsignedp, 1, may_share);
1692 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1693 the insn under examination, VAR is the variable to fix up
1694 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1695 TOPLEVEL is nonzero if this is the main insn chain for this
1699 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel, no_share)
1702 enum machine_mode promoted_mode;
1708 rtx set, prev, prev_set;
1711 /* Remember the notes in case we delete the insn. */
1712 note = REG_NOTES (insn);
1714 /* If this is a CLOBBER of VAR, delete it.
1716 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1717 and REG_RETVAL notes too. */
1718 if (GET_CODE (PATTERN (insn)) == CLOBBER
1719 && (XEXP (PATTERN (insn), 0) == var
1720 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1721 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1722 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1724 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1725 /* The REG_LIBCALL note will go away since we are going to
1726 turn INSN into a NOTE, so just delete the
1727 corresponding REG_RETVAL note. */
1728 remove_note (XEXP (note, 0),
1729 find_reg_note (XEXP (note, 0), REG_RETVAL,
1735 /* The insn to load VAR from a home in the arglist
1736 is now a no-op. When we see it, just delete it.
1737 Similarly if this is storing VAR from a register from which
1738 it was loaded in the previous insn. This will occur
1739 when an ADDRESSOF was made for an arglist slot. */
1741 && (set = single_set (insn)) != 0
1742 && SET_DEST (set) == var
1743 /* If this represents the result of an insn group,
1744 don't delete the insn. */
1745 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1746 && (rtx_equal_p (SET_SRC (set), var)
1747 || (GET_CODE (SET_SRC (set)) == REG
1748 && (prev = prev_nonnote_insn (insn)) != 0
1749 && (prev_set = single_set (prev)) != 0
1750 && SET_DEST (prev_set) == SET_SRC (set)
1751 && rtx_equal_p (SET_SRC (prev_set), var))))
1757 struct fixup_replacement *replacements = 0;
1758 rtx next_insn = NEXT_INSN (insn);
1760 if (SMALL_REGISTER_CLASSES)
1762 /* If the insn that copies the results of a CALL_INSN
1763 into a pseudo now references VAR, we have to use an
1764 intermediate pseudo since we want the life of the
1765 return value register to be only a single insn.
1767 If we don't use an intermediate pseudo, such things as
1768 address computations to make the address of VAR valid
1769 if it is not can be placed between the CALL_INSN and INSN.
1771 To make sure this doesn't happen, we record the destination
1772 of the CALL_INSN and see if the next insn uses both that
1775 if (call_dest != 0 && GET_CODE (insn) == INSN
1776 && reg_mentioned_p (var, PATTERN (insn))
1777 && reg_mentioned_p (call_dest, PATTERN (insn)))
1779 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1781 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1783 PATTERN (insn) = replace_rtx (PATTERN (insn),
1787 if (GET_CODE (insn) == CALL_INSN
1788 && GET_CODE (PATTERN (insn)) == SET)
1789 call_dest = SET_DEST (PATTERN (insn));
1790 else if (GET_CODE (insn) == CALL_INSN
1791 && GET_CODE (PATTERN (insn)) == PARALLEL
1792 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1793 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1798 /* See if we have to do anything to INSN now that VAR is in
1799 memory. If it needs to be loaded into a pseudo, use a single
1800 pseudo for the entire insn in case there is a MATCH_DUP
1801 between two operands. We pass a pointer to the head of
1802 a list of struct fixup_replacements. If fixup_var_refs_1
1803 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1804 it will record them in this list.
1806 If it allocated a pseudo for any replacement, we copy into
1809 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1810 &replacements, no_share);
1812 /* If this is last_parm_insn, and any instructions were output
1813 after it to fix it up, then we must set last_parm_insn to
1814 the last such instruction emitted. */
1815 if (insn == last_parm_insn)
1816 last_parm_insn = PREV_INSN (next_insn);
1818 while (replacements)
1820 struct fixup_replacement *next;
1822 if (GET_CODE (replacements->new) == REG)
1827 /* OLD might be a (subreg (mem)). */
1828 if (GET_CODE (replacements->old) == SUBREG)
1830 = fixup_memory_subreg (replacements->old, insn,
1834 = fixup_stack_1 (replacements->old, insn);
1836 insert_before = insn;
1838 /* If we are changing the mode, do a conversion.
1839 This might be wasteful, but combine.c will
1840 eliminate much of the waste. */
1842 if (GET_MODE (replacements->new)
1843 != GET_MODE (replacements->old))
1846 convert_move (replacements->new,
1847 replacements->old, unsignedp);
1852 seq = gen_move_insn (replacements->new,
1855 emit_insn_before (seq, insert_before);
1858 next = replacements->next;
1859 free (replacements);
1860 replacements = next;
1864 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1865 But don't touch other insns referred to by reg-notes;
1866 we will get them elsewhere. */
1869 if (GET_CODE (note) != INSN_LIST)
1871 = walk_fixup_memory_subreg (XEXP (note, 0), insn,
1873 note = XEXP (note, 1);
1877 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1878 See if the rtx expression at *LOC in INSN needs to be changed.
1880 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1881 contain a list of original rtx's and replacements. If we find that we need
1882 to modify this insn by replacing a memory reference with a pseudo or by
1883 making a new MEM to implement a SUBREG, we consult that list to see if
1884 we have already chosen a replacement. If none has already been allocated,
1885 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1886 or the SUBREG, as appropriate, to the pseudo. */
1889 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements, no_share)
1891 enum machine_mode promoted_mode;
1894 struct fixup_replacement **replacements;
1899 RTX_CODE code = GET_CODE (x);
1902 struct fixup_replacement *replacement;
1907 if (XEXP (x, 0) == var)
1909 /* Prevent sharing of rtl that might lose. */
1910 rtx sub = copy_rtx (XEXP (var, 0));
1912 if (! validate_change (insn, loc, sub, 0))
1914 rtx y = gen_reg_rtx (GET_MODE (sub));
1917 /* We should be able to replace with a register or all is lost.
1918 Note that we can't use validate_change to verify this, since
1919 we're not caring for replacing all dups simultaneously. */
1920 if (! validate_replace_rtx (*loc, y, insn))
1923 /* Careful! First try to recognize a direct move of the
1924 value, mimicking how things are done in gen_reload wrt
1925 PLUS. Consider what happens when insn is a conditional
1926 move instruction and addsi3 clobbers flags. */
1929 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1933 if (recog_memoized (new_insn) < 0)
1935 /* That failed. Fall back on force_operand and hope. */
1938 sub = force_operand (sub, y);
1940 emit_insn (gen_move_insn (y, sub));
1946 /* Don't separate setter from user. */
1947 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1948 insn = PREV_INSN (insn);
1951 emit_insn_before (seq, insn);
1959 /* If we already have a replacement, use it. Otherwise,
1960 try to fix up this address in case it is invalid. */
1962 replacement = find_fixup_replacement (replacements, var);
1963 if (replacement->new)
1965 *loc = replacement->new;
1969 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1971 /* Unless we are forcing memory to register or we changed the mode,
1972 we can leave things the way they are if the insn is valid. */
1974 INSN_CODE (insn) = -1;
1975 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1976 && recog_memoized (insn) >= 0)
1979 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1983 /* If X contains VAR, we need to unshare it here so that we update
1984 each occurrence separately. But all identical MEMs in one insn
1985 must be replaced with the same rtx because of the possibility of
1988 if (reg_mentioned_p (var, x))
1990 replacement = find_fixup_replacement (replacements, x);
1991 if (replacement->new == 0)
1992 replacement->new = copy_most_rtx (x, no_share);
1994 *loc = x = replacement->new;
1995 code = GET_CODE (x);
2012 /* Note that in some cases those types of expressions are altered
2013 by optimize_bit_field, and do not survive to get here. */
2014 if (XEXP (x, 0) == var
2015 || (GET_CODE (XEXP (x, 0)) == SUBREG
2016 && SUBREG_REG (XEXP (x, 0)) == var))
2018 /* Get TEM as a valid MEM in the mode presently in the insn.
2020 We don't worry about the possibility of MATCH_DUP here; it
2021 is highly unlikely and would be tricky to handle. */
2024 if (GET_CODE (tem) == SUBREG)
2026 if (GET_MODE_BITSIZE (GET_MODE (tem))
2027 > GET_MODE_BITSIZE (GET_MODE (var)))
2029 replacement = find_fixup_replacement (replacements, var);
2030 if (replacement->new == 0)
2031 replacement->new = gen_reg_rtx (GET_MODE (var));
2032 SUBREG_REG (tem) = replacement->new;
2034 /* The following code works only if we have a MEM, so we
2035 need to handle the subreg here. We directly substitute
2036 it assuming that a subreg must be OK here. We already
2037 scheduled a replacement to copy the mem into the
2043 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2046 tem = fixup_stack_1 (tem, insn);
2048 /* Unless we want to load from memory, get TEM into the proper mode
2049 for an extract from memory. This can only be done if the
2050 extract is at a constant position and length. */
2052 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2053 && GET_CODE (XEXP (x, 2)) == CONST_INT
2054 && ! mode_dependent_address_p (XEXP (tem, 0))
2055 && ! MEM_VOLATILE_P (tem))
2057 enum machine_mode wanted_mode = VOIDmode;
2058 enum machine_mode is_mode = GET_MODE (tem);
2059 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2061 if (GET_CODE (x) == ZERO_EXTRACT)
2063 enum machine_mode new_mode
2064 = mode_for_extraction (EP_extzv, 1);
2065 if (new_mode != MAX_MACHINE_MODE)
2066 wanted_mode = new_mode;
2068 else if (GET_CODE (x) == SIGN_EXTRACT)
2070 enum machine_mode new_mode
2071 = mode_for_extraction (EP_extv, 1);
2072 if (new_mode != MAX_MACHINE_MODE)
2073 wanted_mode = new_mode;
2076 /* If we have a narrower mode, we can do something. */
2077 if (wanted_mode != VOIDmode
2078 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2080 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2081 rtx old_pos = XEXP (x, 2);
2084 /* If the bytes and bits are counted differently, we
2085 must adjust the offset. */
2086 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2087 offset = (GET_MODE_SIZE (is_mode)
2088 - GET_MODE_SIZE (wanted_mode) - offset);
2090 pos %= GET_MODE_BITSIZE (wanted_mode);
2092 newmem = adjust_address_nv (tem, wanted_mode, offset);
2094 /* Make the change and see if the insn remains valid. */
2095 INSN_CODE (insn) = -1;
2096 XEXP (x, 0) = newmem;
2097 XEXP (x, 2) = GEN_INT (pos);
2099 if (recog_memoized (insn) >= 0)
2102 /* Otherwise, restore old position. XEXP (x, 0) will be
2104 XEXP (x, 2) = old_pos;
2108 /* If we get here, the bitfield extract insn can't accept a memory
2109 reference. Copy the input into a register. */
2111 tem1 = gen_reg_rtx (GET_MODE (tem));
2112 emit_insn_before (gen_move_insn (tem1, tem), insn);
2119 if (SUBREG_REG (x) == var)
2121 /* If this is a special SUBREG made because VAR was promoted
2122 from a wider mode, replace it with VAR and call ourself
2123 recursively, this time saying that the object previously
2124 had its current mode (by virtue of the SUBREG). */
2126 if (SUBREG_PROMOTED_VAR_P (x))
2129 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements,
2134 /* If this SUBREG makes VAR wider, it has become a paradoxical
2135 SUBREG with VAR in memory, but these aren't allowed at this
2136 stage of the compilation. So load VAR into a pseudo and take
2137 a SUBREG of that pseudo. */
2138 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2140 replacement = find_fixup_replacement (replacements, var);
2141 if (replacement->new == 0)
2142 replacement->new = gen_reg_rtx (promoted_mode);
2143 SUBREG_REG (x) = replacement->new;
2147 /* See if we have already found a replacement for this SUBREG.
2148 If so, use it. Otherwise, make a MEM and see if the insn
2149 is recognized. If not, or if we should force MEM into a register,
2150 make a pseudo for this SUBREG. */
2151 replacement = find_fixup_replacement (replacements, x);
2152 if (replacement->new)
2154 *loc = replacement->new;
2158 replacement->new = *loc = fixup_memory_subreg (x, insn,
2161 INSN_CODE (insn) = -1;
2162 if (! flag_force_mem && recog_memoized (insn) >= 0)
2165 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2171 /* First do special simplification of bit-field references. */
2172 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2173 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2174 optimize_bit_field (x, insn, 0);
2175 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2176 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2177 optimize_bit_field (x, insn, 0);
2179 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2180 into a register and then store it back out. */
2181 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2182 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2183 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2184 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2185 > GET_MODE_SIZE (GET_MODE (var))))
2187 replacement = find_fixup_replacement (replacements, var);
2188 if (replacement->new == 0)
2189 replacement->new = gen_reg_rtx (GET_MODE (var));
2191 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2192 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2195 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2196 insn into a pseudo and store the low part of the pseudo into VAR. */
2197 if (GET_CODE (SET_DEST (x)) == SUBREG
2198 && SUBREG_REG (SET_DEST (x)) == var
2199 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2200 > GET_MODE_SIZE (GET_MODE (var))))
2202 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2203 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2210 rtx dest = SET_DEST (x);
2211 rtx src = SET_SRC (x);
2212 rtx outerdest = dest;
2214 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2215 || GET_CODE (dest) == SIGN_EXTRACT
2216 || GET_CODE (dest) == ZERO_EXTRACT)
2217 dest = XEXP (dest, 0);
2219 if (GET_CODE (src) == SUBREG)
2220 src = SUBREG_REG (src);
2222 /* If VAR does not appear at the top level of the SET
2223 just scan the lower levels of the tree. */
2225 if (src != var && dest != var)
2228 /* We will need to rerecognize this insn. */
2229 INSN_CODE (insn) = -1;
2231 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var
2232 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE)
2234 /* Since this case will return, ensure we fixup all the
2236 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2237 insn, replacements, no_share);
2238 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2239 insn, replacements, no_share);
2240 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2241 insn, replacements, no_share);
2243 tem = XEXP (outerdest, 0);
2245 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2246 that may appear inside a ZERO_EXTRACT.
2247 This was legitimate when the MEM was a REG. */
2248 if (GET_CODE (tem) == SUBREG
2249 && SUBREG_REG (tem) == var)
2250 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2252 tem = fixup_stack_1 (tem, insn);
2254 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2255 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2256 && ! mode_dependent_address_p (XEXP (tem, 0))
2257 && ! MEM_VOLATILE_P (tem))
2259 enum machine_mode wanted_mode;
2260 enum machine_mode is_mode = GET_MODE (tem);
2261 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2263 wanted_mode = mode_for_extraction (EP_insv, 0);
2265 /* If we have a narrower mode, we can do something. */
2266 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2268 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2269 rtx old_pos = XEXP (outerdest, 2);
2272 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2273 offset = (GET_MODE_SIZE (is_mode)
2274 - GET_MODE_SIZE (wanted_mode) - offset);
2276 pos %= GET_MODE_BITSIZE (wanted_mode);
2278 newmem = adjust_address_nv (tem, wanted_mode, offset);
2280 /* Make the change and see if the insn remains valid. */
2281 INSN_CODE (insn) = -1;
2282 XEXP (outerdest, 0) = newmem;
2283 XEXP (outerdest, 2) = GEN_INT (pos);
2285 if (recog_memoized (insn) >= 0)
2288 /* Otherwise, restore old position. XEXP (x, 0) will be
2290 XEXP (outerdest, 2) = old_pos;
2294 /* If we get here, the bit-field store doesn't allow memory
2295 or isn't located at a constant position. Load the value into
2296 a register, do the store, and put it back into memory. */
2298 tem1 = gen_reg_rtx (GET_MODE (tem));
2299 emit_insn_before (gen_move_insn (tem1, tem), insn);
2300 emit_insn_after (gen_move_insn (tem, tem1), insn);
2301 XEXP (outerdest, 0) = tem1;
2305 /* STRICT_LOW_PART is a no-op on memory references
2306 and it can cause combinations to be unrecognizable,
2309 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2310 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2312 /* A valid insn to copy VAR into or out of a register
2313 must be left alone, to avoid an infinite loop here.
2314 If the reference to VAR is by a subreg, fix that up,
2315 since SUBREG is not valid for a memref.
2316 Also fix up the address of the stack slot.
2318 Note that we must not try to recognize the insn until
2319 after we know that we have valid addresses and no
2320 (subreg (mem ...) ...) constructs, since these interfere
2321 with determining the validity of the insn. */
2323 if ((SET_SRC (x) == var
2324 || (GET_CODE (SET_SRC (x)) == SUBREG
2325 && SUBREG_REG (SET_SRC (x)) == var))
2326 && (GET_CODE (SET_DEST (x)) == REG
2327 || (GET_CODE (SET_DEST (x)) == SUBREG
2328 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2329 && GET_MODE (var) == promoted_mode
2330 && x == single_set (insn))
2334 if (GET_CODE (SET_SRC (x)) == SUBREG
2335 && (GET_MODE_SIZE (GET_MODE (SET_SRC (x)))
2336 > GET_MODE_SIZE (GET_MODE (var))))
2338 /* This (subreg VAR) is now a paradoxical subreg. We need
2339 to replace VAR instead of the subreg. */
2340 replacement = find_fixup_replacement (replacements, var);
2341 if (replacement->new == NULL_RTX)
2342 replacement->new = gen_reg_rtx (GET_MODE (var));
2343 SUBREG_REG (SET_SRC (x)) = replacement->new;
2347 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2348 if (replacement->new)
2349 SET_SRC (x) = replacement->new;
2350 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2351 SET_SRC (x) = replacement->new
2352 = fixup_memory_subreg (SET_SRC (x), insn, promoted_mode,
2355 SET_SRC (x) = replacement->new
2356 = fixup_stack_1 (SET_SRC (x), insn);
2359 if (recog_memoized (insn) >= 0)
2362 /* INSN is not valid, but we know that we want to
2363 copy SET_SRC (x) to SET_DEST (x) in some way. So
2364 we generate the move and see whether it requires more
2365 than one insn. If it does, we emit those insns and
2366 delete INSN. Otherwise, we can just replace the pattern
2367 of INSN; we have already verified above that INSN has
2368 no other function that to do X. */
2370 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2371 if (NEXT_INSN (pat) != NULL_RTX)
2373 last = emit_insn_before (pat, insn);
2375 /* INSN might have REG_RETVAL or other important notes, so
2376 we need to store the pattern of the last insn in the
2377 sequence into INSN similarly to the normal case. LAST
2378 should not have REG_NOTES, but we allow them if INSN has
2380 if (REG_NOTES (last) && REG_NOTES (insn))
2382 if (REG_NOTES (last))
2383 REG_NOTES (insn) = REG_NOTES (last);
2384 PATTERN (insn) = PATTERN (last);
2389 PATTERN (insn) = PATTERN (pat);
2394 if ((SET_DEST (x) == var
2395 || (GET_CODE (SET_DEST (x)) == SUBREG
2396 && SUBREG_REG (SET_DEST (x)) == var))
2397 && (GET_CODE (SET_SRC (x)) == REG
2398 || (GET_CODE (SET_SRC (x)) == SUBREG
2399 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2400 && GET_MODE (var) == promoted_mode
2401 && x == single_set (insn))
2405 if (GET_CODE (SET_DEST (x)) == SUBREG)
2406 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn,
2409 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2411 if (recog_memoized (insn) >= 0)
2414 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2415 if (NEXT_INSN (pat) != NULL_RTX)
2417 last = emit_insn_before (pat, insn);
2419 /* INSN might have REG_RETVAL or other important notes, so
2420 we need to store the pattern of the last insn in the
2421 sequence into INSN similarly to the normal case. LAST
2422 should not have REG_NOTES, but we allow them if INSN has
2424 if (REG_NOTES (last) && REG_NOTES (insn))
2426 if (REG_NOTES (last))
2427 REG_NOTES (insn) = REG_NOTES (last);
2428 PATTERN (insn) = PATTERN (last);
2433 PATTERN (insn) = PATTERN (pat);
2438 /* Otherwise, storing into VAR must be handled specially
2439 by storing into a temporary and copying that into VAR
2440 with a new insn after this one. Note that this case
2441 will be used when storing into a promoted scalar since
2442 the insn will now have different modes on the input
2443 and output and hence will be invalid (except for the case
2444 of setting it to a constant, which does not need any
2445 change if it is valid). We generate extra code in that case,
2446 but combine.c will eliminate it. */
2451 rtx fixeddest = SET_DEST (x);
2452 enum machine_mode temp_mode;
2454 /* STRICT_LOW_PART can be discarded, around a MEM. */
2455 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2456 fixeddest = XEXP (fixeddest, 0);
2457 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2458 if (GET_CODE (fixeddest) == SUBREG)
2460 fixeddest = fixup_memory_subreg (fixeddest, insn,
2462 temp_mode = GET_MODE (fixeddest);
2466 fixeddest = fixup_stack_1 (fixeddest, insn);
2467 temp_mode = promoted_mode;
2470 temp = gen_reg_rtx (temp_mode);
2472 emit_insn_after (gen_move_insn (fixeddest,
2473 gen_lowpart (GET_MODE (fixeddest),
2477 SET_DEST (x) = temp;
2485 /* Nothing special about this RTX; fix its operands. */
2487 fmt = GET_RTX_FORMAT (code);
2488 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2491 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements,
2493 else if (fmt[i] == 'E')
2496 for (j = 0; j < XVECLEN (x, i); j++)
2497 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2498 insn, replacements, no_share);
2503 /* Previously, X had the form (SUBREG:m1 (REG:PROMOTED_MODE ...)).
2504 The REG was placed on the stack, so X now has the form (SUBREG:m1
2507 Return an rtx (MEM:m1 newaddr) which is equivalent. If any insns
2508 must be emitted to compute NEWADDR, put them before INSN.
2510 UNCRITICAL nonzero means accept paradoxical subregs.
2511 This is used for subregs found inside REG_NOTES. */
2514 fixup_memory_subreg (x, insn, promoted_mode, uncritical)
2517 enum machine_mode promoted_mode;
2521 rtx mem = SUBREG_REG (x);
2522 rtx addr = XEXP (mem, 0);
2523 enum machine_mode mode = GET_MODE (x);
2526 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2527 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (mem)) && ! uncritical)
2530 offset = SUBREG_BYTE (x);
2531 if (BYTES_BIG_ENDIAN)
2532 /* If the PROMOTED_MODE is wider than the mode of the MEM, adjust
2533 the offset so that it points to the right location within the
2535 offset -= (GET_MODE_SIZE (promoted_mode) - GET_MODE_SIZE (GET_MODE (mem)));
2537 if (!flag_force_addr
2538 && memory_address_p (mode, plus_constant (addr, offset)))
2539 /* Shortcut if no insns need be emitted. */
2540 return adjust_address (mem, mode, offset);
2543 result = adjust_address (mem, mode, offset);
2547 emit_insn_before (seq, insn);
2551 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2552 Replace subexpressions of X in place.
2553 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2554 Otherwise return X, with its contents possibly altered.
2556 INSN, PROMOTED_MODE and UNCRITICAL are as for
2557 fixup_memory_subreg. */
2560 walk_fixup_memory_subreg (x, insn, promoted_mode, uncritical)
2563 enum machine_mode promoted_mode;
2573 code = GET_CODE (x);
2575 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2576 return fixup_memory_subreg (x, insn, promoted_mode, uncritical);
2578 /* Nothing special about this RTX; fix its operands. */
2580 fmt = GET_RTX_FORMAT (code);
2581 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2584 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn,
2585 promoted_mode, uncritical);
2586 else if (fmt[i] == 'E')
2589 for (j = 0; j < XVECLEN (x, i); j++)
2591 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn,
2592 promoted_mode, uncritical);
2598 /* For each memory ref within X, if it refers to a stack slot
2599 with an out of range displacement, put the address in a temp register
2600 (emitting new insns before INSN to load these registers)
2601 and alter the memory ref to use that register.
2602 Replace each such MEM rtx with a copy, to avoid clobberage. */
2605 fixup_stack_1 (x, insn)
2610 RTX_CODE code = GET_CODE (x);
2615 rtx ad = XEXP (x, 0);
2616 /* If we have address of a stack slot but it's not valid
2617 (displacement is too large), compute the sum in a register. */
2618 if (GET_CODE (ad) == PLUS
2619 && GET_CODE (XEXP (ad, 0)) == REG
2620 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2621 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2622 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2623 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2624 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2626 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2627 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2628 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2629 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2632 if (memory_address_p (GET_MODE (x), ad))
2636 temp = copy_to_reg (ad);
2639 emit_insn_before (seq, insn);
2640 return replace_equiv_address (x, temp);
2645 fmt = GET_RTX_FORMAT (code);
2646 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2649 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2650 else if (fmt[i] == 'E')
2653 for (j = 0; j < XVECLEN (x, i); j++)
2654 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2660 /* Optimization: a bit-field instruction whose field
2661 happens to be a byte or halfword in memory
2662 can be changed to a move instruction.
2664 We call here when INSN is an insn to examine or store into a bit-field.
2665 BODY is the SET-rtx to be altered.
2667 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2668 (Currently this is called only from function.c, and EQUIV_MEM
2672 optimize_bit_field (body, insn, equiv_mem)
2680 enum machine_mode mode;
2682 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2683 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2684 bitfield = SET_DEST (body), destflag = 1;
2686 bitfield = SET_SRC (body), destflag = 0;
2688 /* First check that the field being stored has constant size and position
2689 and is in fact a byte or halfword suitably aligned. */
2691 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2692 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2693 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2695 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2699 /* Now check that the containing word is memory, not a register,
2700 and that it is safe to change the machine mode. */
2702 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2703 memref = XEXP (bitfield, 0);
2704 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2706 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2707 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2708 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2709 memref = SUBREG_REG (XEXP (bitfield, 0));
2710 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2712 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2713 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2716 && ! mode_dependent_address_p (XEXP (memref, 0))
2717 && ! MEM_VOLATILE_P (memref))
2719 /* Now adjust the address, first for any subreg'ing
2720 that we are now getting rid of,
2721 and then for which byte of the word is wanted. */
2723 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2726 /* Adjust OFFSET to count bits from low-address byte. */
2727 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2728 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2729 - offset - INTVAL (XEXP (bitfield, 1)));
2731 /* Adjust OFFSET to count bytes from low-address byte. */
2732 offset /= BITS_PER_UNIT;
2733 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2735 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2736 / UNITS_PER_WORD) * UNITS_PER_WORD;
2737 if (BYTES_BIG_ENDIAN)
2738 offset -= (MIN (UNITS_PER_WORD,
2739 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2740 - MIN (UNITS_PER_WORD,
2741 GET_MODE_SIZE (GET_MODE (memref))));
2745 memref = adjust_address (memref, mode, offset);
2746 insns = get_insns ();
2748 emit_insn_before (insns, insn);
2750 /* Store this memory reference where
2751 we found the bit field reference. */
2755 validate_change (insn, &SET_DEST (body), memref, 1);
2756 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2758 rtx src = SET_SRC (body);
2759 while (GET_CODE (src) == SUBREG
2760 && SUBREG_BYTE (src) == 0)
2761 src = SUBREG_REG (src);
2762 if (GET_MODE (src) != GET_MODE (memref))
2763 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2764 validate_change (insn, &SET_SRC (body), src, 1);
2766 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2767 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2768 /* This shouldn't happen because anything that didn't have
2769 one of these modes should have got converted explicitly
2770 and then referenced through a subreg.
2771 This is so because the original bit-field was
2772 handled by agg_mode and so its tree structure had
2773 the same mode that memref now has. */
2778 rtx dest = SET_DEST (body);
2780 while (GET_CODE (dest) == SUBREG
2781 && SUBREG_BYTE (dest) == 0
2782 && (GET_MODE_CLASS (GET_MODE (dest))
2783 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2784 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2786 dest = SUBREG_REG (dest);
2788 validate_change (insn, &SET_DEST (body), dest, 1);
2790 if (GET_MODE (dest) == GET_MODE (memref))
2791 validate_change (insn, &SET_SRC (body), memref, 1);
2794 /* Convert the mem ref to the destination mode. */
2795 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2798 convert_move (newreg, memref,
2799 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2803 validate_change (insn, &SET_SRC (body), newreg, 1);
2807 /* See if we can convert this extraction or insertion into
2808 a simple move insn. We might not be able to do so if this
2809 was, for example, part of a PARALLEL.
2811 If we succeed, write out any needed conversions. If we fail,
2812 it is hard to guess why we failed, so don't do anything
2813 special; just let the optimization be suppressed. */
2815 if (apply_change_group () && seq)
2816 emit_insn_before (seq, insn);
2821 /* These routines are responsible for converting virtual register references
2822 to the actual hard register references once RTL generation is complete.
2824 The following four variables are used for communication between the
2825 routines. They contain the offsets of the virtual registers from their
2826 respective hard registers. */
2828 static int in_arg_offset;
2829 static int var_offset;
2830 static int dynamic_offset;
2831 static int out_arg_offset;
2832 static int cfa_offset;
2834 /* In most machines, the stack pointer register is equivalent to the bottom
2837 #ifndef STACK_POINTER_OFFSET
2838 #define STACK_POINTER_OFFSET 0
2841 /* If not defined, pick an appropriate default for the offset of dynamically
2842 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2843 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2845 #ifndef STACK_DYNAMIC_OFFSET
2847 /* The bottom of the stack points to the actual arguments. If
2848 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2849 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2850 stack space for register parameters is not pushed by the caller, but
2851 rather part of the fixed stack areas and hence not included in
2852 `current_function_outgoing_args_size'. Nevertheless, we must allow
2853 for it when allocating stack dynamic objects. */
2855 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2856 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2857 ((ACCUMULATE_OUTGOING_ARGS \
2858 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2859 + (STACK_POINTER_OFFSET)) \
2862 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2863 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2864 + (STACK_POINTER_OFFSET))
2868 /* On most machines, the CFA coincides with the first incoming parm. */
2870 #ifndef ARG_POINTER_CFA_OFFSET
2871 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2874 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had its
2875 address taken. DECL is the decl or SAVE_EXPR for the object stored in the
2876 register, for later use if we do need to force REG into the stack. REG is
2877 overwritten by the MEM like in put_reg_into_stack. */
2880 gen_mem_addressof (reg, decl)
2884 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2887 /* Calculate this before we start messing with decl's RTL. */
2888 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0;
2890 /* If the original REG was a user-variable, then so is the REG whose
2891 address is being taken. Likewise for unchanging. */
2892 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2893 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2895 PUT_CODE (reg, MEM);
2896 MEM_ATTRS (reg) = 0;
2901 tree type = TREE_TYPE (decl);
2902 enum machine_mode decl_mode
2903 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl)));
2904 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl)
2905 : DECL_RTL_IF_SET (decl));
2907 PUT_MODE (reg, decl_mode);
2909 /* Clear DECL_RTL momentarily so functions below will work
2910 properly, then set it again. */
2911 if (DECL_P (decl) && decl_rtl == reg)
2912 SET_DECL_RTL (decl, 0);
2914 set_mem_attributes (reg, decl, 1);
2915 set_mem_alias_set (reg, set);
2917 if (DECL_P (decl) && decl_rtl == reg)
2918 SET_DECL_RTL (decl, reg);
2920 if (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0))
2921 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), reg, 0);
2924 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0);
2929 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2932 flush_addressof (decl)
2935 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2936 && DECL_RTL (decl) != 0
2937 && GET_CODE (DECL_RTL (decl)) == MEM
2938 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2939 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2940 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2943 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2946 put_addressof_into_stack (r, ht)
2951 int volatile_p, used_p;
2953 rtx reg = XEXP (r, 0);
2955 if (GET_CODE (reg) != REG)
2958 decl = ADDRESSOF_DECL (r);
2961 type = TREE_TYPE (decl);
2962 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2963 && TREE_THIS_VOLATILE (decl));
2964 used_p = (TREE_USED (decl)
2965 || (DECL_P (decl) && DECL_INITIAL (decl) != 0));
2974 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2975 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2978 /* List of replacements made below in purge_addressof_1 when creating
2979 bitfield insertions. */
2980 static rtx purge_bitfield_addressof_replacements;
2982 /* List of replacements made below in purge_addressof_1 for patterns
2983 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2984 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2985 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2986 enough in complex cases, e.g. when some field values can be
2987 extracted by usage MEM with narrower mode. */
2988 static rtx purge_addressof_replacements;
2990 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2991 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2992 the stack. If the function returns FALSE then the replacement could not
2996 purge_addressof_1 (loc, insn, force, store, ht)
3008 /* Re-start here to avoid recursion in common cases. */
3015 code = GET_CODE (x);
3017 /* If we don't return in any of the cases below, we will recurse inside
3018 the RTX, which will normally result in any ADDRESSOF being forced into
3022 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
3023 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
3026 else if (code == ADDRESSOF)
3030 if (GET_CODE (XEXP (x, 0)) != MEM)
3031 put_addressof_into_stack (x, ht);
3033 /* We must create a copy of the rtx because it was created by
3034 overwriting a REG rtx which is always shared. */
3035 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
3036 if (validate_change (insn, loc, sub, 0)
3037 || validate_replace_rtx (x, sub, insn))
3041 sub = force_operand (sub, NULL_RTX);
3042 if (! validate_change (insn, loc, sub, 0)
3043 && ! validate_replace_rtx (x, sub, insn))
3046 insns = get_insns ();
3048 emit_insn_before (insns, insn);
3052 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3054 rtx sub = XEXP (XEXP (x, 0), 0);
3056 if (GET_CODE (sub) == MEM)
3057 sub = adjust_address_nv (sub, GET_MODE (x), 0);
3058 else if (GET_CODE (sub) == REG
3059 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3061 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3063 int size_x, size_sub;
3067 /* When processing REG_NOTES look at the list of
3068 replacements done on the insn to find the register that X
3072 for (tem = purge_bitfield_addressof_replacements;
3074 tem = XEXP (XEXP (tem, 1), 1))
3075 if (rtx_equal_p (x, XEXP (tem, 0)))
3077 *loc = XEXP (XEXP (tem, 1), 0);
3081 /* See comment for purge_addressof_replacements. */
3082 for (tem = purge_addressof_replacements;
3084 tem = XEXP (XEXP (tem, 1), 1))
3085 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3087 rtx z = XEXP (XEXP (tem, 1), 0);
3089 if (GET_MODE (x) == GET_MODE (z)
3090 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3091 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3094 /* It can happen that the note may speak of things
3095 in a wider (or just different) mode than the
3096 code did. This is especially true of
3099 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3102 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3103 && (GET_MODE_SIZE (GET_MODE (x))
3104 > GET_MODE_SIZE (GET_MODE (z))))
3106 /* This can occur as a result in invalid
3107 pointer casts, e.g. float f; ...
3108 *(long long int *)&f.
3109 ??? We could emit a warning here, but
3110 without a line number that wouldn't be
3112 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3115 z = gen_lowpart (GET_MODE (x), z);
3121 /* Sometimes we may not be able to find the replacement. For
3122 example when the original insn was a MEM in a wider mode,
3123 and the note is part of a sign extension of a narrowed
3124 version of that MEM. Gcc testcase compile/990829-1.c can
3125 generate an example of this situation. Rather than complain
3126 we return false, which will prompt our caller to remove the
3131 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3132 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3134 /* Don't even consider working with paradoxical subregs,
3135 or the moral equivalent seen here. */
3136 if (size_x <= size_sub
3137 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3139 /* Do a bitfield insertion to mirror what would happen
3146 rtx p = PREV_INSN (insn);
3149 val = gen_reg_rtx (GET_MODE (x));
3150 if (! validate_change (insn, loc, val, 0))
3152 /* Discard the current sequence and put the
3153 ADDRESSOF on stack. */
3159 emit_insn_before (seq, insn);
3160 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3164 store_bit_field (sub, size_x, 0, GET_MODE (x),
3165 val, GET_MODE_SIZE (GET_MODE (sub)));
3167 /* Make sure to unshare any shared rtl that store_bit_field
3168 might have created. */
3169 unshare_all_rtl_again (get_insns ());
3173 p = emit_insn_after (seq, insn);
3174 if (NEXT_INSN (insn))
3175 compute_insns_for_mem (NEXT_INSN (insn),
3176 p ? NEXT_INSN (p) : NULL_RTX,
3181 rtx p = PREV_INSN (insn);
3184 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3185 GET_MODE (x), GET_MODE (x),
3186 GET_MODE_SIZE (GET_MODE (sub)));
3188 if (! validate_change (insn, loc, val, 0))
3190 /* Discard the current sequence and put the
3191 ADDRESSOF on stack. */
3198 emit_insn_before (seq, insn);
3199 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3203 /* Remember the replacement so that the same one can be done
3204 on the REG_NOTES. */
3205 purge_bitfield_addressof_replacements
3206 = gen_rtx_EXPR_LIST (VOIDmode, x,
3209 purge_bitfield_addressof_replacements));
3211 /* We replaced with a reg -- all done. */
3216 else if (validate_change (insn, loc, sub, 0))
3218 /* Remember the replacement so that the same one can be done
3219 on the REG_NOTES. */
3220 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3224 for (tem = purge_addressof_replacements;
3226 tem = XEXP (XEXP (tem, 1), 1))
3227 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3229 XEXP (XEXP (tem, 1), 0) = sub;
3232 purge_addressof_replacements
3233 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3234 gen_rtx_EXPR_LIST (VOIDmode, sub,
3235 purge_addressof_replacements));
3243 /* Scan all subexpressions. */
3244 fmt = GET_RTX_FORMAT (code);
3245 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3248 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0, ht);
3249 else if (*fmt == 'E')
3250 for (j = 0; j < XVECLEN (x, i); j++)
3251 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, ht);
3257 /* Return a hash value for K, a REG. */
3260 insns_for_mem_hash (k)
3263 /* Use the address of the key for the hash value. */
3264 struct insns_for_mem_entry *m = (struct insns_for_mem_entry *) k;
3265 return htab_hash_pointer (m->key);
3268 /* Return nonzero if K1 and K2 (two REGs) are the same. */
3271 insns_for_mem_comp (k1, k2)
3275 struct insns_for_mem_entry *m1 = (struct insns_for_mem_entry *) k1;
3276 struct insns_for_mem_entry *m2 = (struct insns_for_mem_entry *) k2;
3277 return m1->key == m2->key;
3280 struct insns_for_mem_walk_info
3282 /* The hash table that we are using to record which INSNs use which
3286 /* The INSN we are currently processing. */
3289 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3290 to find the insns that use the REGs in the ADDRESSOFs. */
3294 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3295 that might be used in an ADDRESSOF expression, record this INSN in
3296 the hash table given by DATA (which is really a pointer to an
3297 insns_for_mem_walk_info structure). */
3300 insns_for_mem_walk (r, data)
3304 struct insns_for_mem_walk_info *ifmwi
3305 = (struct insns_for_mem_walk_info *) data;
3306 struct insns_for_mem_entry tmp;
3307 tmp.insns = NULL_RTX;
3309 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3310 && GET_CODE (XEXP (*r, 0)) == REG)
3313 tmp.key = XEXP (*r, 0);
3314 e = htab_find_slot (ifmwi->ht, &tmp, INSERT);
3317 *e = ggc_alloc (sizeof (tmp));
3318 memcpy (*e, &tmp, sizeof (tmp));
3321 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3323 struct insns_for_mem_entry *ifme;
3325 ifme = (struct insns_for_mem_entry *) htab_find (ifmwi->ht, &tmp);
3327 /* If we have not already recorded this INSN, do so now. Since
3328 we process the INSNs in order, we know that if we have
3329 recorded it it must be at the front of the list. */
3330 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3331 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3338 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3339 which REGs in HT. */
3342 compute_insns_for_mem (insns, last_insn, ht)
3348 struct insns_for_mem_walk_info ifmwi;
3351 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3352 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3356 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3360 /* Helper function for purge_addressof called through for_each_rtx.
3361 Returns true iff the rtl is an ADDRESSOF. */
3364 is_addressof (rtl, data)
3366 void *data ATTRIBUTE_UNUSED;
3368 return GET_CODE (*rtl) == ADDRESSOF;
3371 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3372 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3376 purge_addressof (insns)
3382 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3383 requires a fixup pass over the instruction stream to correct
3384 INSNs that depended on the REG being a REG, and not a MEM. But,
3385 these fixup passes are slow. Furthermore, most MEMs are not
3386 mentioned in very many instructions. So, we speed up the process
3387 by pre-calculating which REGs occur in which INSNs; that allows
3388 us to perform the fixup passes much more quickly. */
3389 ht = htab_create_ggc (1000, insns_for_mem_hash, insns_for_mem_comp, NULL);
3390 compute_insns_for_mem (insns, NULL_RTX, ht);
3392 for (insn = insns; insn; insn = NEXT_INSN (insn))
3395 if (! purge_addressof_1 (&PATTERN (insn), insn,
3396 asm_noperands (PATTERN (insn)) > 0, 0, ht))
3397 /* If we could not replace the ADDRESSOFs in the insn,
3398 something is wrong. */
3401 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, ht))
3403 /* If we could not replace the ADDRESSOFs in the insn's notes,
3404 we can just remove the offending notes instead. */
3407 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3409 /* If we find a REG_RETVAL note then the insn is a libcall.
3410 Such insns must have REG_EQUAL notes as well, in order
3411 for later passes of the compiler to work. So it is not
3412 safe to delete the notes here, and instead we abort. */
3413 if (REG_NOTE_KIND (note) == REG_RETVAL)
3415 if (for_each_rtx (¬e, is_addressof, NULL))
3416 remove_note (insn, note);
3422 purge_bitfield_addressof_replacements = 0;
3423 purge_addressof_replacements = 0;
3425 /* REGs are shared. purge_addressof will destructively replace a REG
3426 with a MEM, which creates shared MEMs.
3428 Unfortunately, the children of put_reg_into_stack assume that MEMs
3429 referring to the same stack slot are shared (fixup_var_refs and
3430 the associated hash table code).
3432 So, we have to do another unsharing pass after we have flushed any
3433 REGs that had their address taken into the stack.
3435 It may be worth tracking whether or not we converted any REGs into
3436 MEMs to avoid this overhead when it is not needed. */
3437 unshare_all_rtl_again (get_insns ());
3440 /* Convert a SET of a hard subreg to a set of the appropriate hard
3441 register. A subroutine of purge_hard_subreg_sets. */
3444 purge_single_hard_subreg_set (pattern)
3447 rtx reg = SET_DEST (pattern);
3448 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3451 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3452 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3454 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3455 GET_MODE (SUBREG_REG (reg)),
3458 reg = SUBREG_REG (reg);
3462 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3464 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3465 SET_DEST (pattern) = reg;
3469 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3470 only such SETs that we expect to see are those left in because
3471 integrate can't handle sets of parts of a return value register.
3473 We don't use alter_subreg because we only want to eliminate subregs
3474 of hard registers. */
3477 purge_hard_subreg_sets (insn)
3480 for (; insn; insn = NEXT_INSN (insn))
3484 rtx pattern = PATTERN (insn);
3485 switch (GET_CODE (pattern))
3488 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3489 purge_single_hard_subreg_set (pattern);
3494 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3496 rtx inner_pattern = XVECEXP (pattern, 0, j);
3497 if (GET_CODE (inner_pattern) == SET
3498 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3499 purge_single_hard_subreg_set (inner_pattern);
3510 /* Pass through the INSNS of function FNDECL and convert virtual register
3511 references to hard register references. */
3514 instantiate_virtual_regs (fndecl, insns)
3521 /* Compute the offsets to use for this function. */
3522 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3523 var_offset = STARTING_FRAME_OFFSET;
3524 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3525 out_arg_offset = STACK_POINTER_OFFSET;
3526 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3528 /* Scan all variables and parameters of this function. For each that is
3529 in memory, instantiate all virtual registers if the result is a valid
3530 address. If not, we do it later. That will handle most uses of virtual
3531 regs on many machines. */
3532 instantiate_decls (fndecl, 1);
3534 /* Initialize recognition, indicating that volatile is OK. */
3537 /* Scan through all the insns, instantiating every virtual register still
3539 for (insn = insns; insn; insn = NEXT_INSN (insn))
3540 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3541 || GET_CODE (insn) == CALL_INSN)
3543 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3544 if (INSN_DELETED_P (insn))
3546 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3547 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3548 if (GET_CODE (insn) == CALL_INSN)
3549 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3553 /* Instantiate the stack slots for the parm registers, for later use in
3554 addressof elimination. */
3555 for (i = 0; i < max_parm_reg; ++i)
3556 if (parm_reg_stack_loc[i])
3557 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3559 /* Now instantiate the remaining register equivalences for debugging info.
3560 These will not be valid addresses. */
3561 instantiate_decls (fndecl, 0);
3563 /* Indicate that, from now on, assign_stack_local should use
3564 frame_pointer_rtx. */
3565 virtuals_instantiated = 1;
3568 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3569 all virtual registers in their DECL_RTL's.
3571 If VALID_ONLY, do this only if the resulting address is still valid.
3572 Otherwise, always do it. */
3575 instantiate_decls (fndecl, valid_only)
3581 /* Process all parameters of the function. */
3582 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3584 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3585 HOST_WIDE_INT size_rtl;
3587 instantiate_decl (DECL_RTL (decl), size, valid_only);
3589 /* If the parameter was promoted, then the incoming RTL mode may be
3590 larger than the declared type size. We must use the larger of
3592 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3593 size = MAX (size_rtl, size);
3594 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3597 /* Now process all variables defined in the function or its subblocks. */
3598 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3601 /* Subroutine of instantiate_decls: Process all decls in the given
3602 BLOCK node and all its subblocks. */
3605 instantiate_decls_1 (let, valid_only)
3611 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3612 if (DECL_RTL_SET_P (t))
3613 instantiate_decl (DECL_RTL (t),
3614 int_size_in_bytes (TREE_TYPE (t)),
3617 /* Process all subblocks. */
3618 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3619 instantiate_decls_1 (t, valid_only);
3622 /* Subroutine of the preceding procedures: Given RTL representing a
3623 decl and the size of the object, do any instantiation required.
3625 If VALID_ONLY is nonzero, it means that the RTL should only be
3626 changed if the new address is valid. */
3629 instantiate_decl (x, size, valid_only)
3634 enum machine_mode mode;
3637 /* If this is not a MEM, no need to do anything. Similarly if the
3638 address is a constant or a register that is not a virtual register. */
3640 if (x == 0 || GET_CODE (x) != MEM)
3644 if (CONSTANT_P (addr)
3645 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3646 || (GET_CODE (addr) == REG
3647 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3648 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3651 /* If we should only do this if the address is valid, copy the address.
3652 We need to do this so we can undo any changes that might make the
3653 address invalid. This copy is unfortunate, but probably can't be
3657 addr = copy_rtx (addr);
3659 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3661 if (valid_only && size >= 0)
3663 unsigned HOST_WIDE_INT decl_size = size;
3665 /* Now verify that the resulting address is valid for every integer or
3666 floating-point mode up to and including SIZE bytes long. We do this
3667 since the object might be accessed in any mode and frame addresses
3670 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3671 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3672 mode = GET_MODE_WIDER_MODE (mode))
3673 if (! memory_address_p (mode, addr))
3676 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3677 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3678 mode = GET_MODE_WIDER_MODE (mode))
3679 if (! memory_address_p (mode, addr))
3683 /* Put back the address now that we have updated it and we either know
3684 it is valid or we don't care whether it is valid. */
3689 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3690 is a virtual register, return the equivalent hard register and set the
3691 offset indirectly through the pointer. Otherwise, return 0. */
3694 instantiate_new_reg (x, poffset)
3696 HOST_WIDE_INT *poffset;
3699 HOST_WIDE_INT offset;
3701 if (x == virtual_incoming_args_rtx)
3702 new = arg_pointer_rtx, offset = in_arg_offset;
3703 else if (x == virtual_stack_vars_rtx)
3704 new = frame_pointer_rtx, offset = var_offset;
3705 else if (x == virtual_stack_dynamic_rtx)
3706 new = stack_pointer_rtx, offset = dynamic_offset;
3707 else if (x == virtual_outgoing_args_rtx)
3708 new = stack_pointer_rtx, offset = out_arg_offset;
3709 else if (x == virtual_cfa_rtx)
3710 new = arg_pointer_rtx, offset = cfa_offset;
3719 /* Called when instantiate_virtual_regs has failed to update the instruction.
3720 Usually this means that non-matching instruction has been emit, however for
3721 asm statements it may be the problem in the constraints. */
3723 instantiate_virtual_regs_lossage (insn)
3726 if (asm_noperands (PATTERN (insn)) >= 0)
3728 error_for_asm (insn, "impossible constraint in `asm'");
3734 /* Given a pointer to a piece of rtx and an optional pointer to the
3735 containing object, instantiate any virtual registers present in it.
3737 If EXTRA_INSNS, we always do the replacement and generate
3738 any extra insns before OBJECT. If it zero, we do nothing if replacement
3741 Return 1 if we either had nothing to do or if we were able to do the
3742 needed replacement. Return 0 otherwise; we only return zero if
3743 EXTRA_INSNS is zero.
3745 We first try some simple transformations to avoid the creation of extra
3749 instantiate_virtual_regs_1 (loc, object, extra_insns)
3757 HOST_WIDE_INT offset = 0;
3763 /* Re-start here to avoid recursion in common cases. */
3770 /* We may have detected and deleted invalid asm statements. */
3771 if (object && INSN_P (object) && INSN_DELETED_P (object))
3774 code = GET_CODE (x);
3776 /* Check for some special cases. */
3794 /* We are allowed to set the virtual registers. This means that
3795 the actual register should receive the source minus the
3796 appropriate offset. This is used, for example, in the handling
3797 of non-local gotos. */
3798 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3800 rtx src = SET_SRC (x);
3802 /* We are setting the register, not using it, so the relevant
3803 offset is the negative of the offset to use were we using
3806 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3808 /* The only valid sources here are PLUS or REG. Just do
3809 the simplest possible thing to handle them. */
3810 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3812 instantiate_virtual_regs_lossage (object);
3817 if (GET_CODE (src) != REG)
3818 temp = force_operand (src, NULL_RTX);
3821 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3825 emit_insn_before (seq, object);
3828 if (! validate_change (object, &SET_SRC (x), temp, 0)
3830 instantiate_virtual_regs_lossage (object);
3835 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3840 /* Handle special case of virtual register plus constant. */
3841 if (CONSTANT_P (XEXP (x, 1)))
3843 rtx old, new_offset;
3845 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3846 if (GET_CODE (XEXP (x, 0)) == PLUS)
3848 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3850 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3852 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3861 #ifdef POINTERS_EXTEND_UNSIGNED
3862 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3863 we can commute the PLUS and SUBREG because pointers into the
3864 frame are well-behaved. */
3865 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3866 && GET_CODE (XEXP (x, 1)) == CONST_INT
3868 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3870 && validate_change (object, loc,
3871 plus_constant (gen_lowpart (ptr_mode,
3874 + INTVAL (XEXP (x, 1))),
3878 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3880 /* We know the second operand is a constant. Unless the
3881 first operand is a REG (which has been already checked),
3882 it needs to be checked. */
3883 if (GET_CODE (XEXP (x, 0)) != REG)
3891 new_offset = plus_constant (XEXP (x, 1), offset);
3893 /* If the new constant is zero, try to replace the sum with just
3895 if (new_offset == const0_rtx
3896 && validate_change (object, loc, new, 0))
3899 /* Next try to replace the register and new offset.
3900 There are two changes to validate here and we can't assume that
3901 in the case of old offset equals new just changing the register
3902 will yield a valid insn. In the interests of a little efficiency,
3903 however, we only call validate change once (we don't queue up the
3904 changes and then call apply_change_group). */
3908 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3909 : (XEXP (x, 0) = new,
3910 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3918 /* Otherwise copy the new constant into a register and replace
3919 constant with that register. */
3920 temp = gen_reg_rtx (Pmode);
3922 if (validate_change (object, &XEXP (x, 1), temp, 0))
3923 emit_insn_before (gen_move_insn (temp, new_offset), object);
3926 /* If that didn't work, replace this expression with a
3927 register containing the sum. */
3930 new = gen_rtx_PLUS (Pmode, new, new_offset);
3933 temp = force_operand (new, NULL_RTX);
3937 emit_insn_before (seq, object);
3938 if (! validate_change (object, loc, temp, 0)
3939 && ! validate_replace_rtx (x, temp, object))
3941 instantiate_virtual_regs_lossage (object);
3950 /* Fall through to generic two-operand expression case. */
3956 case DIV: case UDIV:
3957 case MOD: case UMOD:
3958 case AND: case IOR: case XOR:
3959 case ROTATERT: case ROTATE:
3960 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3962 case GE: case GT: case GEU: case GTU:
3963 case LE: case LT: case LEU: case LTU:
3964 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3965 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3970 /* Most cases of MEM that convert to valid addresses have already been
3971 handled by our scan of decls. The only special handling we
3972 need here is to make a copy of the rtx to ensure it isn't being
3973 shared if we have to change it to a pseudo.
3975 If the rtx is a simple reference to an address via a virtual register,
3976 it can potentially be shared. In such cases, first try to make it
3977 a valid address, which can also be shared. Otherwise, copy it and
3980 First check for common cases that need no processing. These are
3981 usually due to instantiation already being done on a previous instance
3985 if (CONSTANT_ADDRESS_P (temp)
3986 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3987 || temp == arg_pointer_rtx
3989 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3990 || temp == hard_frame_pointer_rtx
3992 || temp == frame_pointer_rtx)
3995 if (GET_CODE (temp) == PLUS
3996 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3997 && (XEXP (temp, 0) == frame_pointer_rtx
3998 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3999 || XEXP (temp, 0) == hard_frame_pointer_rtx
4001 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4002 || XEXP (temp, 0) == arg_pointer_rtx
4007 if (temp == virtual_stack_vars_rtx
4008 || temp == virtual_incoming_args_rtx
4009 || (GET_CODE (temp) == PLUS
4010 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4011 && (XEXP (temp, 0) == virtual_stack_vars_rtx
4012 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
4014 /* This MEM may be shared. If the substitution can be done without
4015 the need to generate new pseudos, we want to do it in place
4016 so all copies of the shared rtx benefit. The call below will
4017 only make substitutions if the resulting address is still
4020 Note that we cannot pass X as the object in the recursive call
4021 since the insn being processed may not allow all valid
4022 addresses. However, if we were not passed on object, we can
4023 only modify X without copying it if X will have a valid
4026 ??? Also note that this can still lose if OBJECT is an insn that
4027 has less restrictions on an address that some other insn.
4028 In that case, we will modify the shared address. This case
4029 doesn't seem very likely, though. One case where this could
4030 happen is in the case of a USE or CLOBBER reference, but we
4031 take care of that below. */
4033 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
4034 object ? object : x, 0))
4037 /* Otherwise make a copy and process that copy. We copy the entire
4038 RTL expression since it might be a PLUS which could also be
4040 *loc = x = copy_rtx (x);
4043 /* Fall through to generic unary operation case. */
4046 case STRICT_LOW_PART:
4048 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4049 case SIGN_EXTEND: case ZERO_EXTEND:
4050 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4051 case FLOAT: case FIX:
4052 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4057 case POPCOUNT: case PARITY:
4058 /* These case either have just one operand or we know that we need not
4059 check the rest of the operands. */
4065 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4066 go ahead and make the invalid one, but do it to a copy. For a REG,
4067 just make the recursive call, since there's no chance of a problem. */
4069 if ((GET_CODE (XEXP (x, 0)) == MEM
4070 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4072 || (GET_CODE (XEXP (x, 0)) == REG
4073 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4076 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4081 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4082 in front of this insn and substitute the temporary. */
4083 if ((new = instantiate_new_reg (x, &offset)) != 0)
4085 temp = plus_constant (new, offset);
4086 if (!validate_change (object, loc, temp, 0))
4092 temp = force_operand (temp, NULL_RTX);
4096 emit_insn_before (seq, object);
4097 if (! validate_change (object, loc, temp, 0)
4098 && ! validate_replace_rtx (x, temp, object))
4099 instantiate_virtual_regs_lossage (object);
4106 if (GET_CODE (XEXP (x, 0)) == REG)
4109 else if (GET_CODE (XEXP (x, 0)) == MEM)
4111 /* If we have a (addressof (mem ..)), do any instantiation inside
4112 since we know we'll be making the inside valid when we finally
4113 remove the ADDRESSOF. */
4114 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4123 /* Scan all subexpressions. */
4124 fmt = GET_RTX_FORMAT (code);
4125 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4128 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4131 else if (*fmt == 'E')
4132 for (j = 0; j < XVECLEN (x, i); j++)
4133 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4140 /* Optimization: assuming this function does not receive nonlocal gotos,
4141 delete the handlers for such, as well as the insns to establish
4142 and disestablish them. */
4148 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4150 /* Delete the handler by turning off the flag that would
4151 prevent jump_optimize from deleting it.
4152 Also permit deletion of the nonlocal labels themselves
4153 if nothing local refers to them. */
4154 if (GET_CODE (insn) == CODE_LABEL)
4158 LABEL_PRESERVE_P (insn) = 0;
4160 /* Remove it from the nonlocal_label list, to avoid confusing
4162 for (t = nonlocal_labels, last_t = 0; t;
4163 last_t = t, t = TREE_CHAIN (t))
4164 if (DECL_RTL (TREE_VALUE (t)) == insn)
4169 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4171 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4174 if (GET_CODE (insn) == INSN)
4178 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4179 if (reg_mentioned_p (t, PATTERN (insn)))
4185 || (nonlocal_goto_stack_level != 0
4186 && reg_mentioned_p (nonlocal_goto_stack_level,
4188 delete_related_insns (insn);
4193 /* Return the first insn following those generated by `assign_parms'. */
4196 get_first_nonparm_insn ()
4199 return NEXT_INSN (last_parm_insn);
4200 return get_insns ();
4203 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4204 This means a type for which function calls must pass an address to the
4205 function or get an address back from the function.
4206 EXP may be a type node or an expression (whose type is tested). */
4209 aggregate_value_p (exp)
4212 int i, regno, nregs;
4215 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4217 if (TREE_CODE (type) == VOID_TYPE)
4219 if (RETURN_IN_MEMORY (type))
4221 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4222 and thus can't be returned in registers. */
4223 if (TREE_ADDRESSABLE (type))
4225 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4227 /* Make sure we have suitable call-clobbered regs to return
4228 the value in; if not, we must return it in memory. */
4229 reg = hard_function_value (type, 0, 0);
4231 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4233 if (GET_CODE (reg) != REG)
4236 regno = REGNO (reg);
4237 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4238 for (i = 0; i < nregs; i++)
4239 if (! call_used_regs[regno + i])
4244 /* Assign RTL expressions to the function's parameters.
4245 This may involve copying them into registers and using
4246 those registers as the RTL for them. */
4249 assign_parms (fndecl)
4255 CUMULATIVE_ARGS args_so_far;
4256 enum machine_mode promoted_mode, passed_mode;
4257 enum machine_mode nominal_mode, promoted_nominal_mode;
4259 /* Total space needed so far for args on the stack,
4260 given as a constant and a tree-expression. */
4261 struct args_size stack_args_size;
4262 tree fntype = TREE_TYPE (fndecl);
4263 tree fnargs = DECL_ARGUMENTS (fndecl);
4264 /* This is used for the arg pointer when referring to stack args. */
4265 rtx internal_arg_pointer;
4266 /* This is a dummy PARM_DECL that we used for the function result if
4267 the function returns a structure. */
4268 tree function_result_decl = 0;
4269 #ifdef SETUP_INCOMING_VARARGS
4270 int varargs_setup = 0;
4272 rtx conversion_insns = 0;
4273 struct args_size alignment_pad;
4275 /* Nonzero if function takes extra anonymous args.
4276 This means the last named arg must be on the stack
4277 right before the anonymous ones. */
4279 = (TYPE_ARG_TYPES (fntype) != 0
4280 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4281 != void_type_node));
4283 current_function_stdarg = stdarg;
4285 /* If the reg that the virtual arg pointer will be translated into is
4286 not a fixed reg or is the stack pointer, make a copy of the virtual
4287 arg pointer, and address parms via the copy. The frame pointer is
4288 considered fixed even though it is not marked as such.
4290 The second time through, simply use ap to avoid generating rtx. */
4292 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4293 || ! (fixed_regs[ARG_POINTER_REGNUM]
4294 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4295 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4297 internal_arg_pointer = virtual_incoming_args_rtx;
4298 current_function_internal_arg_pointer = internal_arg_pointer;
4300 stack_args_size.constant = 0;
4301 stack_args_size.var = 0;
4303 /* If struct value address is treated as the first argument, make it so. */
4304 if (aggregate_value_p (DECL_RESULT (fndecl))
4305 && ! current_function_returns_pcc_struct
4306 && struct_value_incoming_rtx == 0)
4308 tree type = build_pointer_type (TREE_TYPE (fntype));
4310 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4312 DECL_ARG_TYPE (function_result_decl) = type;
4313 TREE_CHAIN (function_result_decl) = fnargs;
4314 fnargs = function_result_decl;
4317 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4318 parm_reg_stack_loc = (rtx *) ggc_alloc_cleared (max_parm_reg * sizeof (rtx));
4320 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4321 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4323 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, fndecl);
4326 /* We haven't yet found an argument that we must push and pretend the
4328 current_function_pretend_args_size = 0;
4330 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4332 struct args_size stack_offset;
4333 struct args_size arg_size;
4334 int passed_pointer = 0;
4335 int did_conversion = 0;
4336 tree passed_type = DECL_ARG_TYPE (parm);
4337 tree nominal_type = TREE_TYPE (parm);
4339 int last_named = 0, named_arg;
4341 /* Set LAST_NAMED if this is last named arg before last
4347 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4348 if (DECL_NAME (tem))
4354 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4355 most machines, if this is a varargs/stdarg function, then we treat
4356 the last named arg as if it were anonymous too. */
4357 named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4359 if (TREE_TYPE (parm) == error_mark_node
4360 /* This can happen after weird syntax errors
4361 or if an enum type is defined among the parms. */
4362 || TREE_CODE (parm) != PARM_DECL
4363 || passed_type == NULL)
4365 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4366 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4367 TREE_USED (parm) = 1;
4371 /* Find mode of arg as it is passed, and mode of arg
4372 as it should be during execution of this function. */
4373 passed_mode = TYPE_MODE (passed_type);
4374 nominal_mode = TYPE_MODE (nominal_type);
4376 /* If the parm's mode is VOID, its value doesn't matter,
4377 and avoid the usual things like emit_move_insn that could crash. */
4378 if (nominal_mode == VOIDmode)
4380 SET_DECL_RTL (parm, const0_rtx);
4381 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4385 /* If the parm is to be passed as a transparent union, use the
4386 type of the first field for the tests below. We have already
4387 verified that the modes are the same. */
4388 if (DECL_TRANSPARENT_UNION (parm)
4389 || (TREE_CODE (passed_type) == UNION_TYPE
4390 && TYPE_TRANSPARENT_UNION (passed_type)))
4391 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4393 /* See if this arg was passed by invisible reference. It is if
4394 it is an object whose size depends on the contents of the
4395 object itself or if the machine requires these objects be passed
4398 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4399 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4400 || TREE_ADDRESSABLE (passed_type)
4401 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4402 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4403 passed_type, named_arg)
4407 passed_type = nominal_type = build_pointer_type (passed_type);
4409 passed_mode = nominal_mode = Pmode;
4411 /* See if the frontend wants to pass this by invisible reference. */
4412 else if (passed_type != nominal_type
4413 && POINTER_TYPE_P (passed_type)
4414 && TREE_TYPE (passed_type) == nominal_type)
4416 nominal_type = passed_type;
4418 passed_mode = nominal_mode = Pmode;
4421 promoted_mode = passed_mode;
4423 #ifdef PROMOTE_FUNCTION_ARGS
4424 /* Compute the mode in which the arg is actually extended to. */
4425 unsignedp = TREE_UNSIGNED (passed_type);
4426 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4429 /* Let machine desc say which reg (if any) the parm arrives in.
4430 0 means it arrives on the stack. */
4431 #ifdef FUNCTION_INCOMING_ARG
4432 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4433 passed_type, named_arg);
4435 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4436 passed_type, named_arg);
4439 if (entry_parm == 0)
4440 promoted_mode = passed_mode;
4442 #ifdef SETUP_INCOMING_VARARGS
4443 /* If this is the last named parameter, do any required setup for
4444 varargs or stdargs. We need to know about the case of this being an
4445 addressable type, in which case we skip the registers it
4446 would have arrived in.
4448 For stdargs, LAST_NAMED will be set for two parameters, the one that
4449 is actually the last named, and the dummy parameter. We only
4450 want to do this action once.
4452 Also, indicate when RTL generation is to be suppressed. */
4453 if (last_named && !varargs_setup)
4455 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4456 current_function_pretend_args_size, 0);
4461 /* Determine parm's home in the stack,
4462 in case it arrives in the stack or we should pretend it did.
4464 Compute the stack position and rtx where the argument arrives
4467 There is one complexity here: If this was a parameter that would
4468 have been passed in registers, but wasn't only because it is
4469 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4470 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4471 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4472 0 as it was the previous time. */
4474 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4475 locate_and_pad_parm (promoted_mode, passed_type,
4476 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4479 #ifdef FUNCTION_INCOMING_ARG
4480 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4482 pretend_named) != 0,
4484 FUNCTION_ARG (args_so_far, promoted_mode,
4486 pretend_named) != 0,
4489 fndecl, &stack_args_size, &stack_offset, &arg_size,
4493 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4495 if (offset_rtx == const0_rtx)
4496 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4498 stack_parm = gen_rtx_MEM (promoted_mode,
4499 gen_rtx_PLUS (Pmode,
4500 internal_arg_pointer,
4503 set_mem_attributes (stack_parm, parm, 1);
4505 /* Set also REG_ATTRS if parameter was passed in a register. */
4507 set_reg_attrs_for_parm (entry_parm, stack_parm);
4510 /* If this parameter was passed both in registers and in the stack,
4511 use the copy on the stack. */
4512 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4515 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4516 /* If this parm was passed part in regs and part in memory,
4517 pretend it arrived entirely in memory
4518 by pushing the register-part onto the stack.
4520 In the special case of a DImode or DFmode that is split,
4521 we could put it together in a pseudoreg directly,
4522 but for now that's not worth bothering with. */
4526 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4527 passed_type, named_arg);
4531 #if defined (REG_PARM_STACK_SPACE) && !defined (MAYBE_REG_PARM_STACK_SPACE)
4532 /* When REG_PARM_STACK_SPACE is nonzero, stack space for
4533 split parameters was allocated by our caller, so we
4534 won't be pushing it in the prolog. */
4535 if (REG_PARM_STACK_SPACE (fndecl) == 0)
4537 current_function_pretend_args_size
4538 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4539 / (PARM_BOUNDARY / BITS_PER_UNIT)
4540 * (PARM_BOUNDARY / BITS_PER_UNIT));
4542 /* Handle calls that pass values in multiple non-contiguous
4543 locations. The Irix 6 ABI has examples of this. */
4544 if (GET_CODE (entry_parm) == PARALLEL)
4545 emit_group_store (validize_mem (stack_parm), entry_parm,
4546 int_size_in_bytes (TREE_TYPE (parm)));
4549 move_block_from_reg (REGNO (entry_parm),
4550 validize_mem (stack_parm), nregs,
4551 int_size_in_bytes (TREE_TYPE (parm)));
4553 entry_parm = stack_parm;
4558 /* If we didn't decide this parm came in a register,
4559 by default it came on the stack. */
4560 if (entry_parm == 0)
4561 entry_parm = stack_parm;
4563 /* Record permanently how this parm was passed. */
4564 DECL_INCOMING_RTL (parm) = entry_parm;
4566 /* If there is actually space on the stack for this parm,
4567 count it in stack_args_size; otherwise set stack_parm to 0
4568 to indicate there is no preallocated stack slot for the parm. */
4570 if (entry_parm == stack_parm
4571 || (GET_CODE (entry_parm) == PARALLEL
4572 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4573 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4574 /* On some machines, even if a parm value arrives in a register
4575 there is still an (uninitialized) stack slot allocated for it.
4577 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4578 whether this parameter already has a stack slot allocated,
4579 because an arg block exists only if current_function_args_size
4580 is larger than some threshold, and we haven't calculated that
4581 yet. So, for now, we just assume that stack slots never exist
4583 || REG_PARM_STACK_SPACE (fndecl) > 0
4587 stack_args_size.constant += arg_size.constant;
4589 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4592 /* No stack slot was pushed for this parm. */
4595 /* Update info on where next arg arrives in registers. */
4597 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4598 passed_type, named_arg);
4600 /* If we can't trust the parm stack slot to be aligned enough
4601 for its ultimate type, don't use that slot after entry.
4602 We'll make another stack slot, if we need one. */
4604 unsigned int thisparm_boundary
4605 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4607 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4611 /* If parm was passed in memory, and we need to convert it on entry,
4612 don't store it back in that same slot. */
4614 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4617 /* When an argument is passed in multiple locations, we can't
4618 make use of this information, but we can save some copying if
4619 the whole argument is passed in a single register. */
4620 if (GET_CODE (entry_parm) == PARALLEL
4621 && nominal_mode != BLKmode && passed_mode != BLKmode)
4623 int i, len = XVECLEN (entry_parm, 0);
4625 for (i = 0; i < len; i++)
4626 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4627 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4628 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4630 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4632 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4633 DECL_INCOMING_RTL (parm) = entry_parm;
4638 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4639 in the mode in which it arrives.
4640 STACK_PARM is an RTX for a stack slot where the parameter can live
4641 during the function (in case we want to put it there).
4642 STACK_PARM is 0 if no stack slot was pushed for it.
4644 Now output code if necessary to convert ENTRY_PARM to
4645 the type in which this function declares it,
4646 and store that result in an appropriate place,
4647 which may be a pseudo reg, may be STACK_PARM,
4648 or may be a local stack slot if STACK_PARM is 0.
4650 Set DECL_RTL to that place. */
4652 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4654 /* If a BLKmode arrives in registers, copy it to a stack slot.
4655 Handle calls that pass values in multiple non-contiguous
4656 locations. The Irix 6 ABI has examples of this. */
4657 if (GET_CODE (entry_parm) == REG
4658 || GET_CODE (entry_parm) == PARALLEL)
4661 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4664 /* Note that we will be storing an integral number of words.
4665 So we have to be careful to ensure that we allocate an
4666 integral number of words. We do this below in the
4667 assign_stack_local if space was not allocated in the argument
4668 list. If it was, this will not work if PARM_BOUNDARY is not
4669 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4670 if it becomes a problem. */
4672 if (stack_parm == 0)
4675 = assign_stack_local (GET_MODE (entry_parm),
4677 set_mem_attributes (stack_parm, parm, 1);
4680 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4683 /* Handle calls that pass values in multiple non-contiguous
4684 locations. The Irix 6 ABI has examples of this. */
4685 if (GET_CODE (entry_parm) == PARALLEL)
4686 emit_group_store (validize_mem (stack_parm), entry_parm,
4687 int_size_in_bytes (TREE_TYPE (parm)));
4689 move_block_from_reg (REGNO (entry_parm),
4690 validize_mem (stack_parm),
4691 size_stored / UNITS_PER_WORD,
4692 int_size_in_bytes (TREE_TYPE (parm)));
4694 SET_DECL_RTL (parm, stack_parm);
4696 else if (! ((! optimize
4697 && ! DECL_REGISTER (parm))
4698 || TREE_SIDE_EFFECTS (parm)
4699 /* If -ffloat-store specified, don't put explicit
4700 float variables into registers. */
4701 || (flag_float_store
4702 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4703 /* Always assign pseudo to structure return or item passed
4704 by invisible reference. */
4705 || passed_pointer || parm == function_result_decl)
4707 /* Store the parm in a pseudoregister during the function, but we
4708 may need to do it in a wider mode. */
4711 unsigned int regno, regnoi = 0, regnor = 0;
4713 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4715 promoted_nominal_mode
4716 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4718 parmreg = gen_reg_rtx (promoted_nominal_mode);
4719 mark_user_reg (parmreg);
4721 /* If this was an item that we received a pointer to, set DECL_RTL
4725 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4727 set_mem_attributes (x, parm, 1);
4728 SET_DECL_RTL (parm, x);
4732 SET_DECL_RTL (parm, parmreg);
4733 maybe_set_unchanging (DECL_RTL (parm), parm);
4736 /* Copy the value into the register. */
4737 if (nominal_mode != passed_mode
4738 || promoted_nominal_mode != promoted_mode)
4741 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4742 mode, by the caller. We now have to convert it to
4743 NOMINAL_MODE, if different. However, PARMREG may be in
4744 a different mode than NOMINAL_MODE if it is being stored
4747 If ENTRY_PARM is a hard register, it might be in a register
4748 not valid for operating in its mode (e.g., an odd-numbered
4749 register for a DFmode). In that case, moves are the only
4750 thing valid, so we can't do a convert from there. This
4751 occurs when the calling sequence allow such misaligned
4754 In addition, the conversion may involve a call, which could
4755 clobber parameters which haven't been copied to pseudo
4756 registers yet. Therefore, we must first copy the parm to
4757 a pseudo reg here, and save the conversion until after all
4758 parameters have been moved. */
4760 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4762 emit_move_insn (tempreg, validize_mem (entry_parm));
4764 push_to_sequence (conversion_insns);
4765 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4767 if (GET_CODE (tempreg) == SUBREG
4768 && GET_MODE (tempreg) == nominal_mode
4769 && GET_CODE (SUBREG_REG (tempreg)) == REG
4770 && nominal_mode == passed_mode
4771 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4772 && GET_MODE_SIZE (GET_MODE (tempreg))
4773 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4775 /* The argument is already sign/zero extended, so note it
4777 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4778 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4781 /* TREE_USED gets set erroneously during expand_assignment. */
4782 save_tree_used = TREE_USED (parm);
4783 expand_assignment (parm,
4784 make_tree (nominal_type, tempreg), 0, 0);
4785 TREE_USED (parm) = save_tree_used;
4786 conversion_insns = get_insns ();
4791 emit_move_insn (parmreg, validize_mem (entry_parm));
4793 /* If we were passed a pointer but the actual value
4794 can safely live in a register, put it in one. */
4795 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4796 /* If by-reference argument was promoted, demote it. */
4797 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4799 && ! DECL_REGISTER (parm))
4800 || TREE_SIDE_EFFECTS (parm)
4801 /* If -ffloat-store specified, don't put explicit
4802 float variables into registers. */
4803 || (flag_float_store
4804 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4806 /* We can't use nominal_mode, because it will have been set to
4807 Pmode above. We must use the actual mode of the parm. */
4808 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4809 mark_user_reg (parmreg);
4810 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4812 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4813 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4814 push_to_sequence (conversion_insns);
4815 emit_move_insn (tempreg, DECL_RTL (parm));
4817 convert_to_mode (GET_MODE (parmreg),
4820 emit_move_insn (parmreg, DECL_RTL (parm));
4821 conversion_insns = get_insns();
4826 emit_move_insn (parmreg, DECL_RTL (parm));
4827 SET_DECL_RTL (parm, parmreg);
4828 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4832 #ifdef FUNCTION_ARG_CALLEE_COPIES
4833 /* If we are passed an arg by reference and it is our responsibility
4834 to make a copy, do it now.
4835 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4836 original argument, so we must recreate them in the call to
4837 FUNCTION_ARG_CALLEE_COPIES. */
4838 /* ??? Later add code to handle the case that if the argument isn't
4839 modified, don't do the copy. */
4841 else if (passed_pointer
4842 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4843 TYPE_MODE (DECL_ARG_TYPE (parm)),
4844 DECL_ARG_TYPE (parm),
4846 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4849 tree type = DECL_ARG_TYPE (parm);
4851 /* This sequence may involve a library call perhaps clobbering
4852 registers that haven't been copied to pseudos yet. */
4854 push_to_sequence (conversion_insns);
4856 if (!COMPLETE_TYPE_P (type)
4857 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4858 /* This is a variable sized object. */
4859 copy = gen_rtx_MEM (BLKmode,
4860 allocate_dynamic_stack_space
4861 (expr_size (parm), NULL_RTX,
4862 TYPE_ALIGN (type)));
4864 copy = assign_stack_temp (TYPE_MODE (type),
4865 int_size_in_bytes (type), 1);
4866 set_mem_attributes (copy, parm, 1);
4868 store_expr (parm, copy, 0);
4869 emit_move_insn (parmreg, XEXP (copy, 0));
4870 conversion_insns = get_insns ();
4874 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4876 /* In any case, record the parm's desired stack location
4877 in case we later discover it must live in the stack.
4879 If it is a COMPLEX value, store the stack location for both
4882 if (GET_CODE (parmreg) == CONCAT)
4883 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4885 regno = REGNO (parmreg);
4887 if (regno >= max_parm_reg)
4890 int old_max_parm_reg = max_parm_reg;
4892 /* It's slow to expand this one register at a time,
4893 but it's also rare and we need max_parm_reg to be
4894 precisely correct. */
4895 max_parm_reg = regno + 1;
4896 new = (rtx *) ggc_realloc (parm_reg_stack_loc,
4897 max_parm_reg * sizeof (rtx));
4898 memset ((char *) (new + old_max_parm_reg), 0,
4899 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4900 parm_reg_stack_loc = new;
4903 if (GET_CODE (parmreg) == CONCAT)
4905 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4907 regnor = REGNO (gen_realpart (submode, parmreg));
4908 regnoi = REGNO (gen_imagpart (submode, parmreg));
4910 if (stack_parm != 0)
4912 parm_reg_stack_loc[regnor]
4913 = gen_realpart (submode, stack_parm);
4914 parm_reg_stack_loc[regnoi]
4915 = gen_imagpart (submode, stack_parm);
4919 parm_reg_stack_loc[regnor] = 0;
4920 parm_reg_stack_loc[regnoi] = 0;
4924 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4926 /* Mark the register as eliminable if we did no conversion
4927 and it was copied from memory at a fixed offset,
4928 and the arg pointer was not copied to a pseudo-reg.
4929 If the arg pointer is a pseudo reg or the offset formed
4930 an invalid address, such memory-equivalences
4931 as we make here would screw up life analysis for it. */
4932 if (nominal_mode == passed_mode
4935 && GET_CODE (stack_parm) == MEM
4936 && stack_offset.var == 0
4937 && reg_mentioned_p (virtual_incoming_args_rtx,
4938 XEXP (stack_parm, 0)))
4940 rtx linsn = get_last_insn ();
4943 /* Mark complex types separately. */
4944 if (GET_CODE (parmreg) == CONCAT)
4945 /* Scan backwards for the set of the real and
4947 for (sinsn = linsn; sinsn != 0;
4948 sinsn = prev_nonnote_insn (sinsn))
4950 set = single_set (sinsn);
4952 && SET_DEST (set) == regno_reg_rtx [regnoi])
4954 = gen_rtx_EXPR_LIST (REG_EQUIV,
4955 parm_reg_stack_loc[regnoi],
4958 && SET_DEST (set) == regno_reg_rtx [regnor])
4960 = gen_rtx_EXPR_LIST (REG_EQUIV,
4961 parm_reg_stack_loc[regnor],
4964 else if ((set = single_set (linsn)) != 0
4965 && SET_DEST (set) == parmreg)
4967 = gen_rtx_EXPR_LIST (REG_EQUIV,
4968 stack_parm, REG_NOTES (linsn));
4971 /* For pointer data type, suggest pointer register. */
4972 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4973 mark_reg_pointer (parmreg,
4974 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4976 /* If something wants our address, try to use ADDRESSOF. */
4977 if (TREE_ADDRESSABLE (parm))
4979 /* If we end up putting something into the stack,
4980 fixup_var_refs_insns will need to make a pass over
4981 all the instructions. It looks through the pending
4982 sequences -- but it can't see the ones in the
4983 CONVERSION_INSNS, if they're not on the sequence
4984 stack. So, we go back to that sequence, just so that
4985 the fixups will happen. */
4986 push_to_sequence (conversion_insns);
4987 put_var_into_stack (parm);
4988 conversion_insns = get_insns ();
4994 /* Value must be stored in the stack slot STACK_PARM
4995 during function execution. */
4997 if (promoted_mode != nominal_mode)
4999 /* Conversion is required. */
5000 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
5002 emit_move_insn (tempreg, validize_mem (entry_parm));
5004 push_to_sequence (conversion_insns);
5005 entry_parm = convert_to_mode (nominal_mode, tempreg,
5006 TREE_UNSIGNED (TREE_TYPE (parm)));
5008 /* ??? This may need a big-endian conversion on sparc64. */
5009 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
5011 conversion_insns = get_insns ();
5016 if (entry_parm != stack_parm)
5018 if (stack_parm == 0)
5021 = assign_stack_local (GET_MODE (entry_parm),
5022 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
5023 set_mem_attributes (stack_parm, parm, 1);
5026 if (promoted_mode != nominal_mode)
5028 push_to_sequence (conversion_insns);
5029 emit_move_insn (validize_mem (stack_parm),
5030 validize_mem (entry_parm));
5031 conversion_insns = get_insns ();
5035 emit_move_insn (validize_mem (stack_parm),
5036 validize_mem (entry_parm));
5039 SET_DECL_RTL (parm, stack_parm);
5043 /* Output all parameter conversion instructions (possibly including calls)
5044 now that all parameters have been copied out of hard registers. */
5045 emit_insn (conversion_insns);
5047 /* If we are receiving a struct value address as the first argument, set up
5048 the RTL for the function result. As this might require code to convert
5049 the transmitted address to Pmode, we do this here to ensure that possible
5050 preliminary conversions of the address have been emitted already. */
5051 if (function_result_decl)
5053 tree result = DECL_RESULT (fndecl);
5054 rtx addr = DECL_RTL (function_result_decl);
5057 #ifdef POINTERS_EXTEND_UNSIGNED
5058 if (GET_MODE (addr) != Pmode)
5059 addr = convert_memory_address (Pmode, addr);
5062 x = gen_rtx_MEM (DECL_MODE (result), addr);
5063 set_mem_attributes (x, result, 1);
5064 SET_DECL_RTL (result, x);
5067 last_parm_insn = get_last_insn ();
5069 current_function_args_size = stack_args_size.constant;
5071 /* Adjust function incoming argument size for alignment and
5074 #ifdef REG_PARM_STACK_SPACE
5075 #ifndef MAYBE_REG_PARM_STACK_SPACE
5076 current_function_args_size = MAX (current_function_args_size,
5077 REG_PARM_STACK_SPACE (fndecl));
5081 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
5083 current_function_args_size
5084 = ((current_function_args_size + STACK_BYTES - 1)
5085 / STACK_BYTES) * STACK_BYTES;
5087 #ifdef ARGS_GROW_DOWNWARD
5088 current_function_arg_offset_rtx
5089 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5090 : expand_expr (size_diffop (stack_args_size.var,
5091 size_int (-stack_args_size.constant)),
5092 NULL_RTX, VOIDmode, 0));
5094 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5097 /* See how many bytes, if any, of its args a function should try to pop
5100 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5101 current_function_args_size);
5103 /* For stdarg.h function, save info about
5104 regs and stack space used by the named args. */
5106 current_function_args_info = args_so_far;
5108 /* Set the rtx used for the function return value. Put this in its
5109 own variable so any optimizers that need this information don't have
5110 to include tree.h. Do this here so it gets done when an inlined
5111 function gets output. */
5113 current_function_return_rtx
5114 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5115 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5117 /* If scalar return value was computed in a pseudo-reg, or was a named
5118 return value that got dumped to the stack, copy that to the hard
5120 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5122 tree decl_result = DECL_RESULT (fndecl);
5123 rtx decl_rtl = DECL_RTL (decl_result);
5125 if (REG_P (decl_rtl)
5126 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5127 : DECL_REGISTER (decl_result))
5131 #ifdef FUNCTION_OUTGOING_VALUE
5132 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5135 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5138 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5139 /* The delay slot scheduler assumes that current_function_return_rtx
5140 holds the hard register containing the return value, not a
5141 temporary pseudo. */
5142 current_function_return_rtx = real_decl_rtl;
5147 /* Indicate whether REGNO is an incoming argument to the current function
5148 that was promoted to a wider mode. If so, return the RTX for the
5149 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5150 that REGNO is promoted from and whether the promotion was signed or
5153 #ifdef PROMOTE_FUNCTION_ARGS
5156 promoted_input_arg (regno, pmode, punsignedp)
5158 enum machine_mode *pmode;
5163 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5164 arg = TREE_CHAIN (arg))
5165 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5166 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5167 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5169 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5170 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5172 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5173 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5174 && mode != DECL_MODE (arg))
5176 *pmode = DECL_MODE (arg);
5177 *punsignedp = unsignedp;
5178 return DECL_INCOMING_RTL (arg);
5187 /* Compute the size and offset from the start of the stacked arguments for a
5188 parm passed in mode PASSED_MODE and with type TYPE.
5190 INITIAL_OFFSET_PTR points to the current offset into the stacked
5193 The starting offset and size for this parm are returned in *OFFSET_PTR
5194 and *ARG_SIZE_PTR, respectively.
5196 IN_REGS is nonzero if the argument will be passed in registers. It will
5197 never be set if REG_PARM_STACK_SPACE is not defined.
5199 FNDECL is the function in which the argument was defined.
5201 There are two types of rounding that are done. The first, controlled by
5202 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5203 list to be aligned to the specific boundary (in bits). This rounding
5204 affects the initial and starting offsets, but not the argument size.
5206 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5207 optionally rounds the size of the parm to PARM_BOUNDARY. The
5208 initial offset is not affected by this rounding, while the size always
5209 is and the starting offset may be. */
5211 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
5212 initial_offset_ptr is positive because locate_and_pad_parm's
5213 callers pass in the total size of args so far as
5214 initial_offset_ptr. arg_size_ptr is always positive. */
5217 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
5218 initial_offset_ptr, offset_ptr, arg_size_ptr,
5220 enum machine_mode passed_mode;
5222 int in_regs ATTRIBUTE_UNUSED;
5223 tree fndecl ATTRIBUTE_UNUSED;
5224 struct args_size *initial_offset_ptr;
5225 struct args_size *offset_ptr;
5226 struct args_size *arg_size_ptr;
5227 struct args_size *alignment_pad;
5231 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5232 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5233 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5234 #ifdef ARGS_GROW_DOWNWARD
5238 #ifdef REG_PARM_STACK_SPACE
5239 /* If we have found a stack parm before we reach the end of the
5240 area reserved for registers, skip that area. */
5243 int reg_parm_stack_space = 0;
5245 #ifdef MAYBE_REG_PARM_STACK_SPACE
5246 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5248 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5250 if (reg_parm_stack_space > 0)
5252 if (initial_offset_ptr->var)
5254 initial_offset_ptr->var
5255 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5256 ssize_int (reg_parm_stack_space));
5257 initial_offset_ptr->constant = 0;
5259 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5260 initial_offset_ptr->constant = reg_parm_stack_space;
5263 #endif /* REG_PARM_STACK_SPACE */
5265 arg_size_ptr->var = 0;
5266 arg_size_ptr->constant = 0;
5267 alignment_pad->var = 0;
5268 alignment_pad->constant = 0;
5270 #ifdef ARGS_GROW_DOWNWARD
5271 if (initial_offset_ptr->var)
5273 offset_ptr->constant = 0;
5274 offset_ptr->var = size_binop (MINUS_EXPR, ssize_int (0),
5275 initial_offset_ptr->var);
5279 offset_ptr->constant = -initial_offset_ptr->constant;
5280 offset_ptr->var = 0;
5283 if (where_pad != none
5284 && (!host_integerp (sizetree, 1)
5285 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5286 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
5287 SUB_PARM_SIZE (*offset_ptr, s2);
5290 #ifdef REG_PARM_STACK_SPACE
5291 || REG_PARM_STACK_SPACE (fndecl) > 0
5294 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5296 if (initial_offset_ptr->var)
5297 arg_size_ptr->var = size_binop (MINUS_EXPR,
5298 size_binop (MINUS_EXPR,
5300 initial_offset_ptr->var),
5304 arg_size_ptr->constant = (-initial_offset_ptr->constant
5305 - offset_ptr->constant);
5307 /* Pad_below needs the pre-rounded size to know how much to pad below.
5308 We only pad parameters which are not in registers as they have their
5309 padding done elsewhere. */
5310 if (where_pad == downward
5312 pad_below (offset_ptr, passed_mode, sizetree);
5314 #else /* !ARGS_GROW_DOWNWARD */
5316 #ifdef REG_PARM_STACK_SPACE
5317 || REG_PARM_STACK_SPACE (fndecl) > 0
5320 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5321 *offset_ptr = *initial_offset_ptr;
5323 #ifdef PUSH_ROUNDING
5324 if (passed_mode != BLKmode)
5325 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5328 /* Pad_below needs the pre-rounded size to know how much to pad below
5329 so this must be done before rounding up. */
5330 if (where_pad == downward
5331 /* However, BLKmode args passed in regs have their padding done elsewhere.
5332 The stack slot must be able to hold the entire register. */
5333 && !(in_regs && passed_mode == BLKmode))
5334 pad_below (offset_ptr, passed_mode, sizetree);
5336 if (where_pad != none
5337 && (!host_integerp (sizetree, 1)
5338 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5339 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5341 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5342 #endif /* ARGS_GROW_DOWNWARD */
5345 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5346 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5349 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5350 struct args_size *offset_ptr;
5352 struct args_size *alignment_pad;
5354 tree save_var = NULL_TREE;
5355 HOST_WIDE_INT save_constant = 0;
5357 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5359 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5361 save_var = offset_ptr->var;
5362 save_constant = offset_ptr->constant;
5365 alignment_pad->var = NULL_TREE;
5366 alignment_pad->constant = 0;
5368 if (boundary > BITS_PER_UNIT)
5370 if (offset_ptr->var)
5373 #ifdef ARGS_GROW_DOWNWARD
5378 (ARGS_SIZE_TREE (*offset_ptr),
5379 boundary / BITS_PER_UNIT);
5380 offset_ptr->constant = 0; /*?*/
5381 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5382 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5387 offset_ptr->constant =
5388 #ifdef ARGS_GROW_DOWNWARD
5389 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5391 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5393 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5394 alignment_pad->constant = offset_ptr->constant - save_constant;
5400 pad_below (offset_ptr, passed_mode, sizetree)
5401 struct args_size *offset_ptr;
5402 enum machine_mode passed_mode;
5405 if (passed_mode != BLKmode)
5407 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5408 offset_ptr->constant
5409 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5410 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5411 - GET_MODE_SIZE (passed_mode));
5415 if (TREE_CODE (sizetree) != INTEGER_CST
5416 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5418 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5419 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5421 ADD_PARM_SIZE (*offset_ptr, s2);
5422 SUB_PARM_SIZE (*offset_ptr, sizetree);
5427 /* Walk the tree of blocks describing the binding levels within a function
5428 and warn about uninitialized variables.
5429 This is done after calling flow_analysis and before global_alloc
5430 clobbers the pseudo-regs to hard regs. */
5433 uninitialized_vars_warning (block)
5437 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5439 if (warn_uninitialized
5440 && TREE_CODE (decl) == VAR_DECL
5441 /* These warnings are unreliable for and aggregates
5442 because assigning the fields one by one can fail to convince
5443 flow.c that the entire aggregate was initialized.
5444 Unions are troublesome because members may be shorter. */
5445 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5446 && DECL_RTL (decl) != 0
5447 && GET_CODE (DECL_RTL (decl)) == REG
5448 /* Global optimizations can make it difficult to determine if a
5449 particular variable has been initialized. However, a VAR_DECL
5450 with a nonzero DECL_INITIAL had an initializer, so do not
5451 claim it is potentially uninitialized.
5453 We do not care about the actual value in DECL_INITIAL, so we do
5454 not worry that it may be a dangling pointer. */
5455 && DECL_INITIAL (decl) == NULL_TREE
5456 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5457 warning_with_decl (decl,
5458 "`%s' might be used uninitialized in this function");
5460 && TREE_CODE (decl) == VAR_DECL
5461 && DECL_RTL (decl) != 0
5462 && GET_CODE (DECL_RTL (decl)) == REG
5463 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5464 warning_with_decl (decl,
5465 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5467 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5468 uninitialized_vars_warning (sub);
5471 /* Do the appropriate part of uninitialized_vars_warning
5472 but for arguments instead of local variables. */
5475 setjmp_args_warning ()
5478 for (decl = DECL_ARGUMENTS (current_function_decl);
5479 decl; decl = TREE_CHAIN (decl))
5480 if (DECL_RTL (decl) != 0
5481 && GET_CODE (DECL_RTL (decl)) == REG
5482 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5483 warning_with_decl (decl,
5484 "argument `%s' might be clobbered by `longjmp' or `vfork'");
5487 /* If this function call setjmp, put all vars into the stack
5488 unless they were declared `register'. */
5491 setjmp_protect (block)
5495 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5496 if ((TREE_CODE (decl) == VAR_DECL
5497 || TREE_CODE (decl) == PARM_DECL)
5498 && DECL_RTL (decl) != 0
5499 && (GET_CODE (DECL_RTL (decl)) == REG
5500 || (GET_CODE (DECL_RTL (decl)) == MEM
5501 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5502 /* If this variable came from an inline function, it must be
5503 that its life doesn't overlap the setjmp. If there was a
5504 setjmp in the function, it would already be in memory. We
5505 must exclude such variable because their DECL_RTL might be
5506 set to strange things such as virtual_stack_vars_rtx. */
5507 && ! DECL_FROM_INLINE (decl)
5509 #ifdef NON_SAVING_SETJMP
5510 /* If longjmp doesn't restore the registers,
5511 don't put anything in them. */
5515 ! DECL_REGISTER (decl)))
5516 put_var_into_stack (decl);
5517 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5518 setjmp_protect (sub);
5521 /* Like the previous function, but for args instead of local variables. */
5524 setjmp_protect_args ()
5527 for (decl = DECL_ARGUMENTS (current_function_decl);
5528 decl; decl = TREE_CHAIN (decl))
5529 if ((TREE_CODE (decl) == VAR_DECL
5530 || TREE_CODE (decl) == PARM_DECL)
5531 && DECL_RTL (decl) != 0
5532 && (GET_CODE (DECL_RTL (decl)) == REG
5533 || (GET_CODE (DECL_RTL (decl)) == MEM
5534 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5536 /* If longjmp doesn't restore the registers,
5537 don't put anything in them. */
5538 #ifdef NON_SAVING_SETJMP
5542 ! DECL_REGISTER (decl)))
5543 put_var_into_stack (decl);
5546 /* Return the context-pointer register corresponding to DECL,
5547 or 0 if it does not need one. */
5550 lookup_static_chain (decl)
5553 tree context = decl_function_context (decl);
5557 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5560 /* We treat inline_function_decl as an alias for the current function
5561 because that is the inline function whose vars, types, etc.
5562 are being merged into the current function.
5563 See expand_inline_function. */
5564 if (context == current_function_decl || context == inline_function_decl)
5565 return virtual_stack_vars_rtx;
5567 for (link = context_display; link; link = TREE_CHAIN (link))
5568 if (TREE_PURPOSE (link) == context)
5569 return RTL_EXPR_RTL (TREE_VALUE (link));
5574 /* Convert a stack slot address ADDR for variable VAR
5575 (from a containing function)
5576 into an address valid in this function (using a static chain). */
5579 fix_lexical_addr (addr, var)
5584 HOST_WIDE_INT displacement;
5585 tree context = decl_function_context (var);
5586 struct function *fp;
5589 /* If this is the present function, we need not do anything. */
5590 if (context == current_function_decl || context == inline_function_decl)
5593 fp = find_function_data (context);
5595 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5596 addr = XEXP (XEXP (addr, 0), 0);
5598 /* Decode given address as base reg plus displacement. */
5599 if (GET_CODE (addr) == REG)
5600 basereg = addr, displacement = 0;
5601 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5602 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5606 /* We accept vars reached via the containing function's
5607 incoming arg pointer and via its stack variables pointer. */
5608 if (basereg == fp->internal_arg_pointer)
5610 /* If reached via arg pointer, get the arg pointer value
5611 out of that function's stack frame.
5613 There are two cases: If a separate ap is needed, allocate a
5614 slot in the outer function for it and dereference it that way.
5615 This is correct even if the real ap is actually a pseudo.
5616 Otherwise, just adjust the offset from the frame pointer to
5619 #ifdef NEED_SEPARATE_AP
5622 addr = get_arg_pointer_save_area (fp);
5623 addr = fix_lexical_addr (XEXP (addr, 0), var);
5624 addr = memory_address (Pmode, addr);
5626 base = gen_rtx_MEM (Pmode, addr);
5627 set_mem_alias_set (base, get_frame_alias_set ());
5628 base = copy_to_reg (base);
5630 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5631 base = lookup_static_chain (var);
5635 else if (basereg == virtual_stack_vars_rtx)
5637 /* This is the same code as lookup_static_chain, duplicated here to
5638 avoid an extra call to decl_function_context. */
5641 for (link = context_display; link; link = TREE_CHAIN (link))
5642 if (TREE_PURPOSE (link) == context)
5644 base = RTL_EXPR_RTL (TREE_VALUE (link));
5652 /* Use same offset, relative to appropriate static chain or argument
5654 return plus_constant (base, displacement);
5657 /* Return the address of the trampoline for entering nested fn FUNCTION.
5658 If necessary, allocate a trampoline (in the stack frame)
5659 and emit rtl to initialize its contents (at entry to this function). */
5662 trampoline_address (function)
5668 struct function *fp;
5671 /* Find an existing trampoline and return it. */
5672 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5673 if (TREE_PURPOSE (link) == function)
5675 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5677 for (fp = outer_function_chain; fp; fp = fp->outer)
5678 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5679 if (TREE_PURPOSE (link) == function)
5681 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5683 return adjust_trampoline_addr (tramp);
5686 /* None exists; we must make one. */
5688 /* Find the `struct function' for the function containing FUNCTION. */
5690 fn_context = decl_function_context (function);
5691 if (fn_context != current_function_decl
5692 && fn_context != inline_function_decl)
5693 fp = find_function_data (fn_context);
5695 /* Allocate run-time space for this trampoline
5696 (usually in the defining function's stack frame). */
5697 #ifdef ALLOCATE_TRAMPOLINE
5698 tramp = ALLOCATE_TRAMPOLINE (fp);
5700 /* If rounding needed, allocate extra space
5701 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5702 #define TRAMPOLINE_REAL_SIZE \
5703 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5704 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5708 /* Record the trampoline for reuse and note it for later initialization
5709 by expand_function_end. */
5712 rtlexp = make_node (RTL_EXPR);
5713 RTL_EXPR_RTL (rtlexp) = tramp;
5714 fp->x_trampoline_list = tree_cons (function, rtlexp,
5715 fp->x_trampoline_list);
5719 /* Make the RTL_EXPR node temporary, not momentary, so that the
5720 trampoline_list doesn't become garbage. */
5721 rtlexp = make_node (RTL_EXPR);
5723 RTL_EXPR_RTL (rtlexp) = tramp;
5724 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5727 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5728 return adjust_trampoline_addr (tramp);
5731 /* Given a trampoline address,
5732 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5735 round_trampoline_addr (tramp)
5738 /* Round address up to desired boundary. */
5739 rtx temp = gen_reg_rtx (Pmode);
5740 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
5741 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5743 temp = expand_simple_binop (Pmode, PLUS, tramp, addend,
5744 temp, 0, OPTAB_LIB_WIDEN);
5745 tramp = expand_simple_binop (Pmode, AND, temp, mask,
5746 temp, 0, OPTAB_LIB_WIDEN);
5751 /* Given a trampoline address, round it then apply any
5752 platform-specific adjustments so that the result can be used for a
5756 adjust_trampoline_addr (tramp)
5759 tramp = round_trampoline_addr (tramp);
5760 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5761 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5766 /* Put all this function's BLOCK nodes including those that are chained
5767 onto the first block into a vector, and return it.
5768 Also store in each NOTE for the beginning or end of a block
5769 the index of that block in the vector.
5770 The arguments are BLOCK, the chain of top-level blocks of the function,
5771 and INSNS, the insn chain of the function. */
5777 tree *block_vector, *last_block_vector;
5779 tree block = DECL_INITIAL (current_function_decl);
5784 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5785 depth-first order. */
5786 block_vector = get_block_vector (block, &n_blocks);
5787 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5789 last_block_vector = identify_blocks_1 (get_insns (),
5791 block_vector + n_blocks,
5794 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5795 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5796 if (0 && last_block_vector != block_vector + n_blocks)
5799 free (block_vector);
5803 /* Subroutine of identify_blocks. Do the block substitution on the
5804 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5806 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5807 BLOCK_VECTOR is incremented for each block seen. */
5810 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5813 tree *end_block_vector;
5814 tree *orig_block_stack;
5817 tree *block_stack = orig_block_stack;
5819 for (insn = insns; insn; insn = NEXT_INSN (insn))
5821 if (GET_CODE (insn) == NOTE)
5823 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5827 /* If there are more block notes than BLOCKs, something
5829 if (block_vector == end_block_vector)
5832 b = *block_vector++;
5833 NOTE_BLOCK (insn) = b;
5836 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5838 /* If there are more NOTE_INSN_BLOCK_ENDs than
5839 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5840 if (block_stack == orig_block_stack)
5843 NOTE_BLOCK (insn) = *--block_stack;
5846 else if (GET_CODE (insn) == CALL_INSN
5847 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5849 rtx cp = PATTERN (insn);
5851 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5852 end_block_vector, block_stack);
5854 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5855 end_block_vector, block_stack);
5857 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5858 end_block_vector, block_stack);
5862 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5863 something is badly wrong. */
5864 if (block_stack != orig_block_stack)
5867 return block_vector;
5870 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5871 and create duplicate blocks. */
5872 /* ??? Need an option to either create block fragments or to create
5873 abstract origin duplicates of a source block. It really depends
5874 on what optimization has been performed. */
5879 tree block = DECL_INITIAL (current_function_decl);
5880 varray_type block_stack;
5882 if (block == NULL_TREE)
5885 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5887 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
5888 reorder_blocks_0 (block);
5890 /* Prune the old trees away, so that they don't get in the way. */
5891 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5892 BLOCK_CHAIN (block) = NULL_TREE;
5894 /* Recreate the block tree from the note nesting. */
5895 reorder_blocks_1 (get_insns (), block, &block_stack);
5896 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5898 /* Remove deleted blocks from the block fragment chains. */
5899 reorder_fix_fragments (block);
5902 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
5905 reorder_blocks_0 (block)
5910 TREE_ASM_WRITTEN (block) = 0;
5911 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
5912 block = BLOCK_CHAIN (block);
5917 reorder_blocks_1 (insns, current_block, p_block_stack)
5920 varray_type *p_block_stack;
5924 for (insn = insns; insn; insn = NEXT_INSN (insn))
5926 if (GET_CODE (insn) == NOTE)
5928 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5930 tree block = NOTE_BLOCK (insn);
5932 /* If we have seen this block before, that means it now
5933 spans multiple address regions. Create a new fragment. */
5934 if (TREE_ASM_WRITTEN (block))
5936 tree new_block = copy_node (block);
5939 origin = (BLOCK_FRAGMENT_ORIGIN (block)
5940 ? BLOCK_FRAGMENT_ORIGIN (block)
5942 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
5943 BLOCK_FRAGMENT_CHAIN (new_block)
5944 = BLOCK_FRAGMENT_CHAIN (origin);
5945 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
5947 NOTE_BLOCK (insn) = new_block;
5951 BLOCK_SUBBLOCKS (block) = 0;
5952 TREE_ASM_WRITTEN (block) = 1;
5953 BLOCK_SUPERCONTEXT (block) = current_block;
5954 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5955 BLOCK_SUBBLOCKS (current_block) = block;
5956 current_block = block;
5957 VARRAY_PUSH_TREE (*p_block_stack, block);
5959 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5961 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
5962 VARRAY_POP (*p_block_stack);
5963 BLOCK_SUBBLOCKS (current_block)
5964 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5965 current_block = BLOCK_SUPERCONTEXT (current_block);
5968 else if (GET_CODE (insn) == CALL_INSN
5969 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5971 rtx cp = PATTERN (insn);
5972 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
5974 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
5976 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
5981 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
5982 appears in the block tree, select one of the fragments to become
5983 the new origin block. */
5986 reorder_fix_fragments (block)
5991 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
5992 tree new_origin = NULL_TREE;
5996 if (! TREE_ASM_WRITTEN (dup_origin))
5998 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
6000 /* Find the first of the remaining fragments. There must
6001 be at least one -- the current block. */
6002 while (! TREE_ASM_WRITTEN (new_origin))
6003 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
6004 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
6007 else if (! dup_origin)
6010 /* Re-root the rest of the fragments to the new origin. In the
6011 case that DUP_ORIGIN was null, that means BLOCK was the origin
6012 of a chain of fragments and we want to remove those fragments
6013 that didn't make it to the output. */
6016 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
6021 if (TREE_ASM_WRITTEN (chain))
6023 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
6025 pp = &BLOCK_FRAGMENT_CHAIN (chain);
6027 chain = BLOCK_FRAGMENT_CHAIN (chain);
6032 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
6033 block = BLOCK_CHAIN (block);
6037 /* Reverse the order of elements in the chain T of blocks,
6038 and return the new head of the chain (old last element). */
6044 tree prev = 0, decl, next;
6045 for (decl = t; decl; decl = next)
6047 next = BLOCK_CHAIN (decl);
6048 BLOCK_CHAIN (decl) = prev;
6054 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6055 non-NULL, list them all into VECTOR, in a depth-first preorder
6056 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6060 all_blocks (block, vector)
6068 TREE_ASM_WRITTEN (block) = 0;
6070 /* Record this block. */
6072 vector[n_blocks] = block;
6076 /* Record the subblocks, and their subblocks... */
6077 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6078 vector ? vector + n_blocks : 0);
6079 block = BLOCK_CHAIN (block);
6085 /* Return a vector containing all the blocks rooted at BLOCK. The
6086 number of elements in the vector is stored in N_BLOCKS_P. The
6087 vector is dynamically allocated; it is the caller's responsibility
6088 to call `free' on the pointer returned. */
6091 get_block_vector (block, n_blocks_p)
6097 *n_blocks_p = all_blocks (block, NULL);
6098 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
6099 all_blocks (block, block_vector);
6101 return block_vector;
6104 static GTY(()) int next_block_index = 2;
6106 /* Set BLOCK_NUMBER for all the blocks in FN. */
6116 /* For SDB and XCOFF debugging output, we start numbering the blocks
6117 from 1 within each function, rather than keeping a running
6119 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6120 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6121 next_block_index = 1;
6124 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6126 /* The top-level BLOCK isn't numbered at all. */
6127 for (i = 1; i < n_blocks; ++i)
6128 /* We number the blocks from two. */
6129 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6131 free (block_vector);
6136 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6139 debug_find_var_in_block_tree (var, block)
6145 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6149 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6151 tree ret = debug_find_var_in_block_tree (var, t);
6159 /* Allocate a function structure and reset its contents to the defaults. */
6162 prepare_function_start ()
6164 cfun = (struct function *) ggc_alloc_cleared (sizeof (struct function));
6166 init_stmt_for_function ();
6167 init_eh_for_function ();
6169 cse_not_expected = ! optimize;
6171 /* Caller save not needed yet. */
6172 caller_save_needed = 0;
6174 /* No stack slots have been made yet. */
6175 stack_slot_list = 0;
6177 current_function_has_nonlocal_label = 0;
6178 current_function_has_nonlocal_goto = 0;
6180 /* There is no stack slot for handling nonlocal gotos. */
6181 nonlocal_goto_handler_slots = 0;
6182 nonlocal_goto_stack_level = 0;
6184 /* No labels have been declared for nonlocal use. */
6185 nonlocal_labels = 0;
6186 nonlocal_goto_handler_labels = 0;
6188 /* No function calls so far in this function. */
6189 function_call_count = 0;
6191 /* No parm regs have been allocated.
6192 (This is important for output_inline_function.) */
6193 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6195 /* Initialize the RTL mechanism. */
6198 /* Initialize the queue of pending postincrement and postdecrements,
6199 and some other info in expr.c. */
6202 /* We haven't done register allocation yet. */
6205 init_varasm_status (cfun);
6207 /* Clear out data used for inlining. */
6208 cfun->inlinable = 0;
6209 cfun->original_decl_initial = 0;
6210 cfun->original_arg_vector = 0;
6212 cfun->stack_alignment_needed = STACK_BOUNDARY;
6213 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6215 /* Set if a call to setjmp is seen. */
6216 current_function_calls_setjmp = 0;
6218 /* Set if a call to longjmp is seen. */
6219 current_function_calls_longjmp = 0;
6221 current_function_calls_alloca = 0;
6222 current_function_calls_eh_return = 0;
6223 current_function_calls_constant_p = 0;
6224 current_function_contains_functions = 0;
6225 current_function_is_leaf = 0;
6226 current_function_nothrow = 0;
6227 current_function_sp_is_unchanging = 0;
6228 current_function_uses_only_leaf_regs = 0;
6229 current_function_has_computed_jump = 0;
6230 current_function_is_thunk = 0;
6232 current_function_returns_pcc_struct = 0;
6233 current_function_returns_struct = 0;
6234 current_function_epilogue_delay_list = 0;
6235 current_function_uses_const_pool = 0;
6236 current_function_uses_pic_offset_table = 0;
6237 current_function_cannot_inline = 0;
6239 /* We have not yet needed to make a label to jump to for tail-recursion. */
6240 tail_recursion_label = 0;
6242 /* We haven't had a need to make a save area for ap yet. */
6243 arg_pointer_save_area = 0;
6245 /* No stack slots allocated yet. */
6248 /* No SAVE_EXPRs in this function yet. */
6251 /* No RTL_EXPRs in this function yet. */
6254 /* Set up to allocate temporaries. */
6257 /* Indicate that we need to distinguish between the return value of the
6258 present function and the return value of a function being called. */
6259 rtx_equal_function_value_matters = 1;
6261 /* Indicate that we have not instantiated virtual registers yet. */
6262 virtuals_instantiated = 0;
6264 /* Indicate that we want CONCATs now. */
6265 generating_concat_p = 1;
6267 /* Indicate we have no need of a frame pointer yet. */
6268 frame_pointer_needed = 0;
6270 /* By default assume not stdarg. */
6271 current_function_stdarg = 0;
6273 /* We haven't made any trampolines for this function yet. */
6274 trampoline_list = 0;
6276 init_pending_stack_adjust ();
6277 inhibit_defer_pop = 0;
6279 current_function_outgoing_args_size = 0;
6281 current_function_funcdef_no = funcdef_no++;
6283 cfun->arc_profile = profile_arc_flag || flag_test_coverage;
6285 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
6287 cfun->max_jumptable_ents = 0;
6289 (*lang_hooks.function.init) (cfun);
6290 if (init_machine_status)
6291 cfun->machine = (*init_machine_status) ();
6294 /* Initialize the rtl expansion mechanism so that we can do simple things
6295 like generate sequences. This is used to provide a context during global
6296 initialization of some passes. */
6298 init_dummy_function_start ()
6300 prepare_function_start ();
6303 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6304 and initialize static variables for generating RTL for the statements
6308 init_function_start (subr, filename, line)
6310 const char *filename;
6313 prepare_function_start ();
6315 current_function_name = (*lang_hooks.decl_printable_name) (subr, 2);
6318 /* Nonzero if this is a nested function that uses a static chain. */
6320 current_function_needs_context
6321 = (decl_function_context (current_function_decl) != 0
6322 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6324 /* Within function body, compute a type's size as soon it is laid out. */
6325 immediate_size_expand++;
6327 /* Prevent ever trying to delete the first instruction of a function.
6328 Also tell final how to output a linenum before the function prologue.
6329 Note linenums could be missing, e.g. when compiling a Java .class file. */
6331 emit_line_note (filename, line);
6333 /* Make sure first insn is a note even if we don't want linenums.
6334 This makes sure the first insn will never be deleted.
6335 Also, final expects a note to appear there. */
6336 emit_note (NULL, NOTE_INSN_DELETED);
6338 /* Set flags used by final.c. */
6339 if (aggregate_value_p (DECL_RESULT (subr)))
6341 #ifdef PCC_STATIC_STRUCT_RETURN
6342 current_function_returns_pcc_struct = 1;
6344 current_function_returns_struct = 1;
6347 /* Warn if this value is an aggregate type,
6348 regardless of which calling convention we are using for it. */
6349 if (warn_aggregate_return
6350 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6351 warning ("function returns an aggregate");
6353 current_function_returns_pointer
6354 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
6357 /* Make sure all values used by the optimization passes have sane
6360 init_function_for_compilation ()
6364 /* No prologue/epilogue insns yet. */
6365 VARRAY_GROW (prologue, 0);
6366 VARRAY_GROW (epilogue, 0);
6367 VARRAY_GROW (sibcall_epilogue, 0);
6370 /* Expand a call to __main at the beginning of a possible main function. */
6372 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6373 #undef HAS_INIT_SECTION
6374 #define HAS_INIT_SECTION
6378 expand_main_function ()
6380 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6381 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6383 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6387 /* Forcibly align the stack. */
6388 #ifdef STACK_GROWS_DOWNWARD
6389 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6390 stack_pointer_rtx, 1, OPTAB_WIDEN);
6392 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6393 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6394 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6395 stack_pointer_rtx, 1, OPTAB_WIDEN);
6397 if (tmp != stack_pointer_rtx)
6398 emit_move_insn (stack_pointer_rtx, tmp);
6400 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6401 tmp = force_reg (Pmode, const0_rtx);
6402 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6406 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6407 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6410 emit_insn_before (seq, tmp);
6416 #ifndef HAS_INIT_SECTION
6417 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), LCT_NORMAL,
6422 /* The PENDING_SIZES represent the sizes of variable-sized types.
6423 Create RTL for the various sizes now (using temporary variables),
6424 so that we can refer to the sizes from the RTL we are generating
6425 for the current function. The PENDING_SIZES are a TREE_LIST. The
6426 TREE_VALUE of each node is a SAVE_EXPR. */
6429 expand_pending_sizes (pending_sizes)
6434 /* Evaluate now the sizes of any types declared among the arguments. */
6435 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6437 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6438 /* Flush the queue in case this parameter declaration has
6444 /* Start the RTL for a new function, and set variables used for
6446 SUBR is the FUNCTION_DECL node.
6447 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6448 the function's parameters, which must be run at any return statement. */
6451 expand_function_start (subr, parms_have_cleanups)
6453 int parms_have_cleanups;
6456 rtx last_ptr = NULL_RTX;
6458 /* Make sure volatile mem refs aren't considered
6459 valid operands of arithmetic insns. */
6460 init_recog_no_volatile ();
6462 current_function_instrument_entry_exit
6463 = (flag_instrument_function_entry_exit
6464 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6466 current_function_profile
6468 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6470 current_function_limit_stack
6471 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6473 /* If function gets a static chain arg, store it in the stack frame.
6474 Do this first, so it gets the first stack slot offset. */
6475 if (current_function_needs_context)
6477 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6479 /* Delay copying static chain if it is not a register to avoid
6480 conflicts with regs used for parameters. */
6481 if (! SMALL_REGISTER_CLASSES
6482 || GET_CODE (static_chain_incoming_rtx) == REG)
6483 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6486 /* If the parameters of this function need cleaning up, get a label
6487 for the beginning of the code which executes those cleanups. This must
6488 be done before doing anything with return_label. */
6489 if (parms_have_cleanups)
6490 cleanup_label = gen_label_rtx ();
6494 /* Make the label for return statements to jump to. Do not special
6495 case machines with special return instructions -- they will be
6496 handled later during jump, ifcvt, or epilogue creation. */
6497 return_label = gen_label_rtx ();
6499 /* Initialize rtx used to return the value. */
6500 /* Do this before assign_parms so that we copy the struct value address
6501 before any library calls that assign parms might generate. */
6503 /* Decide whether to return the value in memory or in a register. */
6504 if (aggregate_value_p (DECL_RESULT (subr)))
6506 /* Returning something that won't go in a register. */
6507 rtx value_address = 0;
6509 #ifdef PCC_STATIC_STRUCT_RETURN
6510 if (current_function_returns_pcc_struct)
6512 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6513 value_address = assemble_static_space (size);
6518 /* Expect to be passed the address of a place to store the value.
6519 If it is passed as an argument, assign_parms will take care of
6521 if (struct_value_incoming_rtx)
6523 value_address = gen_reg_rtx (Pmode);
6524 emit_move_insn (value_address, struct_value_incoming_rtx);
6529 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6530 set_mem_attributes (x, DECL_RESULT (subr), 1);
6531 SET_DECL_RTL (DECL_RESULT (subr), x);
6534 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6535 /* If return mode is void, this decl rtl should not be used. */
6536 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6539 /* Compute the return values into a pseudo reg, which we will copy
6540 into the true return register after the cleanups are done. */
6542 /* In order to figure out what mode to use for the pseudo, we
6543 figure out what the mode of the eventual return register will
6544 actually be, and use that. */
6546 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6549 /* Structures that are returned in registers are not aggregate_value_p,
6550 so we may see a PARALLEL or a REG. */
6551 if (REG_P (hard_reg))
6552 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6553 else if (GET_CODE (hard_reg) == PARALLEL)
6554 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
6558 /* Set DECL_REGISTER flag so that expand_function_end will copy the
6559 result to the real return register(s). */
6560 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6563 /* Initialize rtx for parameters and local variables.
6564 In some cases this requires emitting insns. */
6566 assign_parms (subr);
6568 /* Copy the static chain now if it wasn't a register. The delay is to
6569 avoid conflicts with the parameter passing registers. */
6571 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6572 if (GET_CODE (static_chain_incoming_rtx) != REG)
6573 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6575 /* The following was moved from init_function_start.
6576 The move is supposed to make sdb output more accurate. */
6577 /* Indicate the beginning of the function body,
6578 as opposed to parm setup. */
6579 emit_note (NULL, NOTE_INSN_FUNCTION_BEG);
6581 if (GET_CODE (get_last_insn ()) != NOTE)
6582 emit_note (NULL, NOTE_INSN_DELETED);
6583 parm_birth_insn = get_last_insn ();
6585 context_display = 0;
6586 if (current_function_needs_context)
6588 /* Fetch static chain values for containing functions. */
6589 tem = decl_function_context (current_function_decl);
6590 /* Copy the static chain pointer into a pseudo. If we have
6591 small register classes, copy the value from memory if
6592 static_chain_incoming_rtx is a REG. */
6595 /* If the static chain originally came in a register, put it back
6596 there, then move it out in the next insn. The reason for
6597 this peculiar code is to satisfy function integration. */
6598 if (SMALL_REGISTER_CLASSES
6599 && GET_CODE (static_chain_incoming_rtx) == REG)
6600 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6601 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6606 tree rtlexp = make_node (RTL_EXPR);
6608 RTL_EXPR_RTL (rtlexp) = last_ptr;
6609 context_display = tree_cons (tem, rtlexp, context_display);
6610 tem = decl_function_context (tem);
6613 /* Chain thru stack frames, assuming pointer to next lexical frame
6614 is found at the place we always store it. */
6615 #ifdef FRAME_GROWS_DOWNWARD
6616 last_ptr = plus_constant (last_ptr,
6617 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6619 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6620 set_mem_alias_set (last_ptr, get_frame_alias_set ());
6621 last_ptr = copy_to_reg (last_ptr);
6623 /* If we are not optimizing, ensure that we know that this
6624 piece of context is live over the entire function. */
6626 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6631 if (current_function_instrument_entry_exit)
6633 rtx fun = DECL_RTL (current_function_decl);
6634 if (GET_CODE (fun) == MEM)
6635 fun = XEXP (fun, 0);
6638 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode,
6640 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6642 hard_frame_pointer_rtx),
6646 if (current_function_profile)
6649 PROFILE_HOOK (current_function_funcdef_no);
6653 /* After the display initializations is where the tail-recursion label
6654 should go, if we end up needing one. Ensure we have a NOTE here
6655 since some things (like trampolines) get placed before this. */
6656 tail_recursion_reentry = emit_note (NULL, NOTE_INSN_DELETED);
6658 /* Evaluate now the sizes of any types declared among the arguments. */
6659 expand_pending_sizes (nreverse (get_pending_sizes ()));
6661 /* Make sure there is a line number after the function entry setup code. */
6662 force_next_line_note ();
6665 /* Undo the effects of init_dummy_function_start. */
6667 expand_dummy_function_end ()
6669 /* End any sequences that failed to be closed due to syntax errors. */
6670 while (in_sequence_p ())
6673 /* Outside function body, can't compute type's actual size
6674 until next function's body starts. */
6676 free_after_parsing (cfun);
6677 free_after_compilation (cfun);
6681 /* Call DOIT for each hard register used as a return value from
6682 the current function. */
6685 diddle_return_value (doit, arg)
6686 void (*doit) PARAMS ((rtx, void *));
6689 rtx outgoing = current_function_return_rtx;
6694 if (GET_CODE (outgoing) == REG)
6695 (*doit) (outgoing, arg);
6696 else if (GET_CODE (outgoing) == PARALLEL)
6700 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6702 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6704 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6711 do_clobber_return_reg (reg, arg)
6713 void *arg ATTRIBUTE_UNUSED;
6715 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6719 clobber_return_register ()
6721 diddle_return_value (do_clobber_return_reg, NULL);
6723 /* In case we do use pseudo to return value, clobber it too. */
6724 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6726 tree decl_result = DECL_RESULT (current_function_decl);
6727 rtx decl_rtl = DECL_RTL (decl_result);
6728 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6730 do_clobber_return_reg (decl_rtl, NULL);
6736 do_use_return_reg (reg, arg)
6738 void *arg ATTRIBUTE_UNUSED;
6740 emit_insn (gen_rtx_USE (VOIDmode, reg));
6744 use_return_register ()
6746 diddle_return_value (do_use_return_reg, NULL);
6749 static GTY(()) rtx initial_trampoline;
6751 /* Generate RTL for the end of the current function.
6752 FILENAME and LINE are the current position in the source file.
6754 It is up to language-specific callers to do cleanups for parameters--
6755 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6758 expand_function_end (filename, line, end_bindings)
6759 const char *filename;
6766 finish_expr_for_function ();
6768 /* If arg_pointer_save_area was referenced only from a nested
6769 function, we will not have initialized it yet. Do that now. */
6770 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6771 get_arg_pointer_save_area (cfun);
6773 #ifdef NON_SAVING_SETJMP
6774 /* Don't put any variables in registers if we call setjmp
6775 on a machine that fails to restore the registers. */
6776 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6778 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6779 setjmp_protect (DECL_INITIAL (current_function_decl));
6781 setjmp_protect_args ();
6785 /* Initialize any trampolines required by this function. */
6786 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6788 tree function = TREE_PURPOSE (link);
6789 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6790 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6791 #ifdef TRAMPOLINE_TEMPLATE
6796 #ifdef TRAMPOLINE_TEMPLATE
6797 /* First make sure this compilation has a template for
6798 initializing trampolines. */
6799 if (initial_trampoline == 0)
6802 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6803 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
6807 /* Generate insns to initialize the trampoline. */
6809 tramp = round_trampoline_addr (XEXP (tramp, 0));
6810 #ifdef TRAMPOLINE_TEMPLATE
6811 blktramp = replace_equiv_address (initial_trampoline, tramp);
6812 emit_block_move (blktramp, initial_trampoline,
6813 GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL);
6815 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6819 /* Put those insns at entry to the containing function (this one). */
6820 emit_insn_before (seq, tail_recursion_reentry);
6823 /* If we are doing stack checking and this function makes calls,
6824 do a stack probe at the start of the function to ensure we have enough
6825 space for another stack frame. */
6826 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6830 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6831 if (GET_CODE (insn) == CALL_INSN)
6834 probe_stack_range (STACK_CHECK_PROTECT,
6835 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6838 emit_insn_before (seq, tail_recursion_reentry);
6843 /* Warn about unused parms if extra warnings were specified. */
6844 /* Either ``-Wextra -Wunused'' or ``-Wunused-parameter'' enables this
6845 warning. WARN_UNUSED_PARAMETER is negative when set by
6846 -Wunused. Note that -Wall implies -Wunused, so ``-Wall -Wextra'' will
6847 also give these warnings. */
6848 if (warn_unused_parameter > 0
6849 || (warn_unused_parameter < 0 && extra_warnings))
6853 for (decl = DECL_ARGUMENTS (current_function_decl);
6854 decl; decl = TREE_CHAIN (decl))
6855 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6856 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6857 warning_with_decl (decl, "unused parameter `%s'");
6860 /* Delete handlers for nonlocal gotos if nothing uses them. */
6861 if (nonlocal_goto_handler_slots != 0
6862 && ! current_function_has_nonlocal_label)
6865 /* End any sequences that failed to be closed due to syntax errors. */
6866 while (in_sequence_p ())
6869 /* Outside function body, can't compute type's actual size
6870 until next function's body starts. */
6871 immediate_size_expand--;
6873 clear_pending_stack_adjust ();
6874 do_pending_stack_adjust ();
6876 /* Mark the end of the function body.
6877 If control reaches this insn, the function can drop through
6878 without returning a value. */
6879 emit_note (NULL, NOTE_INSN_FUNCTION_END);
6881 /* Must mark the last line number note in the function, so that the test
6882 coverage code can avoid counting the last line twice. This just tells
6883 the code to ignore the immediately following line note, since there
6884 already exists a copy of this note somewhere above. This line number
6885 note is still needed for debugging though, so we can't delete it. */
6886 if (flag_test_coverage)
6887 emit_note (NULL, NOTE_INSN_REPEATED_LINE_NUMBER);
6889 /* Output a linenumber for the end of the function.
6890 SDB depends on this. */
6891 emit_line_note_force (filename, line);
6893 /* Before the return label (if any), clobber the return
6894 registers so that they are not propagated live to the rest of
6895 the function. This can only happen with functions that drop
6896 through; if there had been a return statement, there would
6897 have either been a return rtx, or a jump to the return label.
6899 We delay actual code generation after the current_function_value_rtx
6901 clobber_after = get_last_insn ();
6903 /* Output the label for the actual return from the function,
6904 if one is expected. This happens either because a function epilogue
6905 is used instead of a return instruction, or because a return was done
6906 with a goto in order to run local cleanups, or because of pcc-style
6907 structure returning. */
6909 emit_label (return_label);
6911 /* C++ uses this. */
6913 expand_end_bindings (0, 0, 0);
6915 if (current_function_instrument_entry_exit)
6917 rtx fun = DECL_RTL (current_function_decl);
6918 if (GET_CODE (fun) == MEM)
6919 fun = XEXP (fun, 0);
6922 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode,
6924 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6926 hard_frame_pointer_rtx),
6930 /* Let except.c know where it should emit the call to unregister
6931 the function context for sjlj exceptions. */
6932 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
6933 sjlj_emit_function_exit_after (get_last_insn ());
6935 /* If we had calls to alloca, and this machine needs
6936 an accurate stack pointer to exit the function,
6937 insert some code to save and restore the stack pointer. */
6938 #ifdef EXIT_IGNORE_STACK
6939 if (! EXIT_IGNORE_STACK)
6941 if (current_function_calls_alloca)
6945 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6946 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6949 /* If scalar return value was computed in a pseudo-reg, or was a named
6950 return value that got dumped to the stack, copy that to the hard
6952 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6954 tree decl_result = DECL_RESULT (current_function_decl);
6955 rtx decl_rtl = DECL_RTL (decl_result);
6957 if (REG_P (decl_rtl)
6958 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
6959 : DECL_REGISTER (decl_result))
6961 rtx real_decl_rtl = current_function_return_rtx;
6963 /* This should be set in assign_parms. */
6964 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
6967 /* If this is a BLKmode structure being returned in registers,
6968 then use the mode computed in expand_return. Note that if
6969 decl_rtl is memory, then its mode may have been changed,
6970 but that current_function_return_rtx has not. */
6971 if (GET_MODE (real_decl_rtl) == BLKmode)
6972 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
6974 /* If a named return value dumped decl_return to memory, then
6975 we may need to re-do the PROMOTE_MODE signed/unsigned
6977 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
6979 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
6981 #ifdef PROMOTE_FUNCTION_RETURN
6982 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
6986 convert_move (real_decl_rtl, decl_rtl, unsignedp);
6988 else if (GET_CODE (real_decl_rtl) == PARALLEL)
6990 /* If expand_function_start has created a PARALLEL for decl_rtl,
6991 move the result to the real return registers. Otherwise, do
6992 a group load from decl_rtl for a named return. */
6993 if (GET_CODE (decl_rtl) == PARALLEL)
6994 emit_group_move (real_decl_rtl, decl_rtl);
6996 emit_group_load (real_decl_rtl, decl_rtl,
6997 int_size_in_bytes (TREE_TYPE (decl_result)));
7000 emit_move_insn (real_decl_rtl, decl_rtl);
7004 /* If returning a structure, arrange to return the address of the value
7005 in a place where debuggers expect to find it.
7007 If returning a structure PCC style,
7008 the caller also depends on this value.
7009 And current_function_returns_pcc_struct is not necessarily set. */
7010 if (current_function_returns_struct
7011 || current_function_returns_pcc_struct)
7014 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
7015 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
7016 #ifdef FUNCTION_OUTGOING_VALUE
7018 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
7019 current_function_decl);
7022 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
7025 /* Mark this as a function return value so integrate will delete the
7026 assignment and USE below when inlining this function. */
7027 REG_FUNCTION_VALUE_P (outgoing) = 1;
7029 #ifdef POINTERS_EXTEND_UNSIGNED
7030 /* The address may be ptr_mode and OUTGOING may be Pmode. */
7031 if (GET_MODE (outgoing) != GET_MODE (value_address))
7032 value_address = convert_memory_address (GET_MODE (outgoing),
7036 emit_move_insn (outgoing, value_address);
7038 /* Show return register used to hold result (in this case the address
7040 current_function_return_rtx = outgoing;
7043 /* If this is an implementation of throw, do what's necessary to
7044 communicate between __builtin_eh_return and the epilogue. */
7045 expand_eh_return ();
7047 /* Emit the actual code to clobber return register. */
7052 clobber_return_register ();
7056 after = emit_insn_after (seq, clobber_after);
7058 if (clobber_after != after)
7059 cfun->x_clobber_return_insn = after;
7062 /* ??? This should no longer be necessary since stupid is no longer with
7063 us, but there are some parts of the compiler (eg reload_combine, and
7064 sh mach_dep_reorg) that still try and compute their own lifetime info
7065 instead of using the general framework. */
7066 use_return_register ();
7068 /* Fix up any gotos that jumped out to the outermost
7069 binding level of the function.
7070 Must follow emitting RETURN_LABEL. */
7072 /* If you have any cleanups to do at this point,
7073 and they need to create temporary variables,
7074 then you will lose. */
7075 expand_fixups (get_insns ());
7079 get_arg_pointer_save_area (f)
7082 rtx ret = f->x_arg_pointer_save_area;
7086 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
7087 f->x_arg_pointer_save_area = ret;
7090 if (f == cfun && ! f->arg_pointer_save_area_init)
7094 /* Save the arg pointer at the beginning of the function. The
7095 generated stack slot may not be a valid memory address, so we
7096 have to check it and fix it if necessary. */
7098 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
7102 push_topmost_sequence ();
7103 emit_insn_after (seq, get_insns ());
7104 pop_topmost_sequence ();
7110 /* Extend a vector that records the INSN_UIDs of INSNS
7111 (a list of one or more insns). */
7114 record_insns (insns, vecp)
7123 while (tmp != NULL_RTX)
7126 tmp = NEXT_INSN (tmp);
7129 i = VARRAY_SIZE (*vecp);
7130 VARRAY_GROW (*vecp, i + len);
7132 while (tmp != NULL_RTX)
7134 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
7136 tmp = NEXT_INSN (tmp);
7140 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
7141 be running after reorg, SEQUENCE rtl is possible. */
7144 contains (insn, vec)
7150 if (GET_CODE (insn) == INSN
7151 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7154 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7155 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7156 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7162 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7163 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7170 prologue_epilogue_contains (insn)
7173 if (contains (insn, prologue))
7175 if (contains (insn, epilogue))
7181 sibcall_epilogue_contains (insn)
7184 if (sibcall_epilogue)
7185 return contains (insn, sibcall_epilogue);
7190 /* Insert gen_return at the end of block BB. This also means updating
7191 block_for_insn appropriately. */
7194 emit_return_into_block (bb, line_note)
7198 emit_jump_insn_after (gen_return (), bb->end);
7200 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
7201 NOTE_LINE_NUMBER (line_note), PREV_INSN (bb->end));
7203 #endif /* HAVE_return */
7205 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7207 /* These functions convert the epilogue into a variant that does not modify the
7208 stack pointer. This is used in cases where a function returns an object
7209 whose size is not known until it is computed. The called function leaves the
7210 object on the stack, leaves the stack depressed, and returns a pointer to
7213 What we need to do is track all modifications and references to the stack
7214 pointer, deleting the modifications and changing the references to point to
7215 the location the stack pointer would have pointed to had the modifications
7218 These functions need to be portable so we need to make as few assumptions
7219 about the epilogue as we can. However, the epilogue basically contains
7220 three things: instructions to reset the stack pointer, instructions to
7221 reload registers, possibly including the frame pointer, and an
7222 instruction to return to the caller.
7224 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7225 We also make no attempt to validate the insns we make since if they are
7226 invalid, we probably can't do anything valid. The intent is that these
7227 routines get "smarter" as more and more machines start to use them and
7228 they try operating on different epilogues.
7230 We use the following structure to track what the part of the epilogue that
7231 we've already processed has done. We keep two copies of the SP equivalence,
7232 one for use during the insn we are processing and one for use in the next
7233 insn. The difference is because one part of a PARALLEL may adjust SP
7234 and the other may use it. */
7238 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7239 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7240 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7241 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7242 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7243 should be set to once we no longer need
7247 static void handle_epilogue_set PARAMS ((rtx, struct epi_info *));
7248 static void emit_equiv_load PARAMS ((struct epi_info *));
7250 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
7251 no modifications to the stack pointer. Return the new list of insns. */
7254 keep_stack_depressed (insns)
7258 struct epi_info info;
7261 /* If the epilogue is just a single instruction, it ust be OK as is. */
7263 if (NEXT_INSN (insns) == NULL_RTX)
7266 /* Otherwise, start a sequence, initialize the information we have, and
7267 process all the insns we were given. */
7270 info.sp_equiv_reg = stack_pointer_rtx;
7272 info.equiv_reg_src = 0;
7276 while (insn != NULL_RTX)
7278 next = NEXT_INSN (insn);
7287 /* If this insn references the register that SP is equivalent to and
7288 we have a pending load to that register, we must force out the load
7289 first and then indicate we no longer know what SP's equivalent is. */
7290 if (info.equiv_reg_src != 0
7291 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7293 emit_equiv_load (&info);
7294 info.sp_equiv_reg = 0;
7297 info.new_sp_equiv_reg = info.sp_equiv_reg;
7298 info.new_sp_offset = info.sp_offset;
7300 /* If this is a (RETURN) and the return address is on the stack,
7301 update the address and change to an indirect jump. */
7302 if (GET_CODE (PATTERN (insn)) == RETURN
7303 || (GET_CODE (PATTERN (insn)) == PARALLEL
7304 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7306 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7308 HOST_WIDE_INT offset = 0;
7309 rtx jump_insn, jump_set;
7311 /* If the return address is in a register, we can emit the insn
7312 unchanged. Otherwise, it must be a MEM and we see what the
7313 base register and offset are. In any case, we have to emit any
7314 pending load to the equivalent reg of SP, if any. */
7315 if (GET_CODE (retaddr) == REG)
7317 emit_equiv_load (&info);
7322 else if (GET_CODE (retaddr) == MEM
7323 && GET_CODE (XEXP (retaddr, 0)) == REG)
7324 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7325 else if (GET_CODE (retaddr) == MEM
7326 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7327 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7328 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7330 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7331 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7336 /* If the base of the location containing the return pointer
7337 is SP, we must update it with the replacement address. Otherwise,
7338 just build the necessary MEM. */
7339 retaddr = plus_constant (base, offset);
7340 if (base == stack_pointer_rtx)
7341 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7342 plus_constant (info.sp_equiv_reg,
7345 retaddr = gen_rtx_MEM (Pmode, retaddr);
7347 /* If there is a pending load to the equivalent register for SP
7348 and we reference that register, we must load our address into
7349 a scratch register and then do that load. */
7350 if (info.equiv_reg_src
7351 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7356 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7357 if (HARD_REGNO_MODE_OK (regno, Pmode)
7358 && !fixed_regs[regno]
7359 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7360 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7362 && !refers_to_regno_p (regno,
7363 regno + HARD_REGNO_NREGS (regno,
7365 info.equiv_reg_src, NULL))
7368 if (regno == FIRST_PSEUDO_REGISTER)
7371 reg = gen_rtx_REG (Pmode, regno);
7372 emit_move_insn (reg, retaddr);
7376 emit_equiv_load (&info);
7377 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7379 /* Show the SET in the above insn is a RETURN. */
7380 jump_set = single_set (jump_insn);
7384 SET_IS_RETURN_P (jump_set) = 1;
7387 /* If SP is not mentioned in the pattern and its equivalent register, if
7388 any, is not modified, just emit it. Otherwise, if neither is set,
7389 replace the reference to SP and emit the insn. If none of those are
7390 true, handle each SET individually. */
7391 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7392 && (info.sp_equiv_reg == stack_pointer_rtx
7393 || !reg_set_p (info.sp_equiv_reg, insn)))
7395 else if (! reg_set_p (stack_pointer_rtx, insn)
7396 && (info.sp_equiv_reg == stack_pointer_rtx
7397 || !reg_set_p (info.sp_equiv_reg, insn)))
7399 if (! validate_replace_rtx (stack_pointer_rtx,
7400 plus_constant (info.sp_equiv_reg,
7407 else if (GET_CODE (PATTERN (insn)) == SET)
7408 handle_epilogue_set (PATTERN (insn), &info);
7409 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7411 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7412 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7413 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7418 info.sp_equiv_reg = info.new_sp_equiv_reg;
7419 info.sp_offset = info.new_sp_offset;
7424 insns = get_insns ();
7429 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7430 structure that contains information about what we've seen so far. We
7431 process this SET by either updating that data or by emitting one or
7435 handle_epilogue_set (set, p)
7439 /* First handle the case where we are setting SP. Record what it is being
7440 set from. If unknown, abort. */
7441 if (reg_set_p (stack_pointer_rtx, set))
7443 if (SET_DEST (set) != stack_pointer_rtx)
7446 if (GET_CODE (SET_SRC (set)) == PLUS
7447 && GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7449 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7450 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7453 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7455 /* If we are adjusting SP, we adjust from the old data. */
7456 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7458 p->new_sp_equiv_reg = p->sp_equiv_reg;
7459 p->new_sp_offset += p->sp_offset;
7462 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7468 /* Next handle the case where we are setting SP's equivalent register.
7469 If we already have a value to set it to, abort. We could update, but
7470 there seems little point in handling that case. Note that we have
7471 to allow for the case where we are setting the register set in
7472 the previous part of a PARALLEL inside a single insn. But use the
7473 old offset for any updates within this insn. */
7474 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7476 if (!rtx_equal_p (p->new_sp_equiv_reg, SET_DEST (set))
7477 || p->equiv_reg_src != 0)
7481 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7482 plus_constant (p->sp_equiv_reg,
7486 /* Otherwise, replace any references to SP in the insn to its new value
7487 and emit the insn. */
7490 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7491 plus_constant (p->sp_equiv_reg,
7493 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7494 plus_constant (p->sp_equiv_reg,
7500 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7506 if (p->equiv_reg_src != 0)
7507 emit_move_insn (p->sp_equiv_reg, p->equiv_reg_src);
7509 p->equiv_reg_src = 0;
7513 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7514 this into place with notes indicating where the prologue ends and where
7515 the epilogue begins. Update the basic block information when possible. */
7518 thread_prologue_and_epilogue_insns (f)
7519 rtx f ATTRIBUTE_UNUSED;
7523 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7526 #ifdef HAVE_prologue
7527 rtx prologue_end = NULL_RTX;
7529 #if defined (HAVE_epilogue) || defined(HAVE_return)
7530 rtx epilogue_end = NULL_RTX;
7533 #ifdef HAVE_prologue
7537 seq = gen_prologue ();
7540 /* Retain a map of the prologue insns. */
7541 record_insns (seq, &prologue);
7542 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
7547 /* Can't deal with multiple successors of the entry block
7548 at the moment. Function should always have at least one
7550 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7553 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7558 /* If the exit block has no non-fake predecessors, we don't need
7560 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7561 if ((e->flags & EDGE_FAKE) == 0)
7567 if (optimize && HAVE_return)
7569 /* If we're allowed to generate a simple return instruction,
7570 then by definition we don't need a full epilogue. Examine
7571 the block that falls through to EXIT. If it does not
7572 contain any code, examine its predecessors and try to
7573 emit (conditional) return instructions. */
7579 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7580 if (e->flags & EDGE_FALLTHRU)
7586 /* Verify that there are no active instructions in the last block. */
7588 while (label && GET_CODE (label) != CODE_LABEL)
7590 if (active_insn_p (label))
7592 label = PREV_INSN (label);
7595 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7597 rtx epilogue_line_note = NULL_RTX;
7599 /* Locate the line number associated with the closing brace,
7600 if we can find one. */
7601 for (seq = get_last_insn ();
7602 seq && ! active_insn_p (seq);
7603 seq = PREV_INSN (seq))
7604 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7606 epilogue_line_note = seq;
7610 for (e = last->pred; e; e = e_next)
7612 basic_block bb = e->src;
7615 e_next = e->pred_next;
7616 if (bb == ENTRY_BLOCK_PTR)
7620 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7623 /* If we have an unconditional jump, we can replace that
7624 with a simple return instruction. */
7625 if (simplejump_p (jump))
7627 emit_return_into_block (bb, epilogue_line_note);
7631 /* If we have a conditional jump, we can try to replace
7632 that with a conditional return instruction. */
7633 else if (condjump_p (jump))
7635 if (! redirect_jump (jump, 0, 0))
7638 /* If this block has only one successor, it both jumps
7639 and falls through to the fallthru block, so we can't
7641 if (bb->succ->succ_next == NULL)
7647 /* Fix up the CFG for the successful change we just made. */
7648 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7651 /* Emit a return insn for the exit fallthru block. Whether
7652 this is still reachable will be determined later. */
7654 emit_barrier_after (last->end);
7655 emit_return_into_block (last, epilogue_line_note);
7656 epilogue_end = last->end;
7657 last->succ->flags &= ~EDGE_FALLTHRU;
7662 #ifdef HAVE_epilogue
7665 /* Find the edge that falls through to EXIT. Other edges may exist
7666 due to RETURN instructions, but those don't need epilogues.
7667 There really shouldn't be a mixture -- either all should have
7668 been converted or none, however... */
7670 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7671 if (e->flags & EDGE_FALLTHRU)
7677 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
7679 seq = gen_epilogue ();
7681 #ifdef INCOMING_RETURN_ADDR_RTX
7682 /* If this function returns with the stack depressed and we can support
7683 it, massage the epilogue to actually do that. */
7684 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7685 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7686 seq = keep_stack_depressed (seq);
7689 emit_jump_insn (seq);
7691 /* Retain a map of the epilogue insns. */
7692 record_insns (seq, &epilogue);
7697 insert_insn_on_edge (seq, e);
7704 commit_edge_insertions ();
7706 #ifdef HAVE_sibcall_epilogue
7707 /* Emit sibling epilogues before any sibling call sites. */
7708 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7710 basic_block bb = e->src;
7715 if (GET_CODE (insn) != CALL_INSN
7716 || ! SIBLING_CALL_P (insn))
7720 emit_insn (gen_sibcall_epilogue ());
7724 /* Retain a map of the epilogue insns. Used in life analysis to
7725 avoid getting rid of sibcall epilogue insns. Do this before we
7726 actually emit the sequence. */
7727 record_insns (seq, &sibcall_epilogue);
7729 i = PREV_INSN (insn);
7730 newinsn = emit_insn_before (seq, insn);
7734 #ifdef HAVE_prologue
7739 /* GDB handles `break f' by setting a breakpoint on the first
7740 line note after the prologue. Which means (1) that if
7741 there are line number notes before where we inserted the
7742 prologue we should move them, and (2) we should generate a
7743 note before the end of the first basic block, if there isn't
7746 ??? This behavior is completely broken when dealing with
7747 multiple entry functions. We simply place the note always
7748 into first basic block and let alternate entry points
7752 for (insn = prologue_end; insn; insn = prev)
7754 prev = PREV_INSN (insn);
7755 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7757 /* Note that we cannot reorder the first insn in the
7758 chain, since rest_of_compilation relies on that
7759 remaining constant. */
7762 reorder_insns (insn, insn, prologue_end);
7766 /* Find the last line number note in the first block. */
7767 for (insn = ENTRY_BLOCK_PTR->next_bb->end;
7768 insn != prologue_end && insn;
7769 insn = PREV_INSN (insn))
7770 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7773 /* If we didn't find one, make a copy of the first line number
7777 for (insn = next_active_insn (prologue_end);
7779 insn = PREV_INSN (insn))
7780 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7782 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7783 NOTE_LINE_NUMBER (insn),
7790 #ifdef HAVE_epilogue
7795 /* Similarly, move any line notes that appear after the epilogue.
7796 There is no need, however, to be quite so anal about the existence
7798 for (insn = epilogue_end; insn; insn = next)
7800 next = NEXT_INSN (insn);
7801 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7802 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7808 /* Reposition the prologue-end and epilogue-begin notes after instruction
7809 scheduling and delayed branch scheduling. */
7812 reposition_prologue_and_epilogue_notes (f)
7813 rtx f ATTRIBUTE_UNUSED;
7815 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7816 rtx insn, last, note;
7819 if ((len = VARRAY_SIZE (prologue)) > 0)
7823 /* Scan from the beginning until we reach the last prologue insn.
7824 We apparently can't depend on basic_block_{head,end} after
7826 for (insn = f; insn; insn = NEXT_INSN (insn))
7828 if (GET_CODE (insn) == NOTE)
7830 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7833 else if (contains (insn, prologue))
7843 /* Find the prologue-end note if we haven't already, and
7844 move it to just after the last prologue insn. */
7847 for (note = last; (note = NEXT_INSN (note));)
7848 if (GET_CODE (note) == NOTE
7849 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7853 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7854 if (GET_CODE (last) == CODE_LABEL)
7855 last = NEXT_INSN (last);
7856 reorder_insns (note, note, last);
7860 if ((len = VARRAY_SIZE (epilogue)) > 0)
7864 /* Scan from the end until we reach the first epilogue insn.
7865 We apparently can't depend on basic_block_{head,end} after
7867 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
7869 if (GET_CODE (insn) == NOTE)
7871 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7874 else if (contains (insn, epilogue))
7884 /* Find the epilogue-begin note if we haven't already, and
7885 move it to just before the first epilogue insn. */
7888 for (note = insn; (note = PREV_INSN (note));)
7889 if (GET_CODE (note) == NOTE
7890 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7894 if (PREV_INSN (last) != note)
7895 reorder_insns (note, note, PREV_INSN (last));
7898 #endif /* HAVE_prologue or HAVE_epilogue */
7901 /* Called once, at initialization, to initialize function.c. */
7904 init_function_once ()
7906 VARRAY_INT_INIT (prologue, 0, "prologue");
7907 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7908 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
7911 #include "gt-function.h"