1 /* Expands front end tree to back end RTL for GCC.
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"
54 #include "hard-reg-set.h"
55 #include "insn-config.h"
58 #include "basic-block.h"
63 #include "integrate.h"
64 #include "langhooks.h"
67 #ifndef TRAMPOLINE_ALIGNMENT
68 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
71 #ifndef LOCAL_ALIGNMENT
72 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
75 #ifndef STACK_ALIGNMENT_NEEDED
76 #define STACK_ALIGNMENT_NEEDED 1
79 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
81 /* Some systems use __main in a way incompatible with its use in gcc, in these
82 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
83 give the same symbol without quotes for an alternative entry point. You
84 must define both, or neither. */
86 #define NAME__MAIN "__main"
89 /* Round a value to the lowest integer less than it that is a multiple of
90 the required alignment. Avoid using division in case the value is
91 negative. Assume the alignment is a power of two. */
92 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
94 /* Similar, but round to the next highest integer that meets the
96 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
98 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
99 during rtl generation. If they are different register numbers, this is
100 always true. It may also be true if
101 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
102 generation. See fix_lexical_addr for details. */
104 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
105 #define NEED_SEPARATE_AP
108 /* Nonzero if function being compiled doesn't contain any calls
109 (ignoring the prologue and epilogue). This is set prior to
110 local register allocation and is valid for the remaining
112 int current_function_is_leaf;
114 /* Nonzero if function being compiled doesn't contain any instructions
115 that can throw an exception. This is set prior to final. */
117 int current_function_nothrow;
119 /* Nonzero if function being compiled doesn't modify the stack pointer
120 (ignoring the prologue and epilogue). This is only valid after
121 life_analysis has run. */
122 int current_function_sp_is_unchanging;
124 /* Nonzero if the function being compiled is a leaf function which only
125 uses leaf registers. This is valid after reload (specifically after
126 sched2) and is useful only if the port defines LEAF_REGISTERS. */
127 int current_function_uses_only_leaf_regs;
129 /* Nonzero once virtual register instantiation has been done.
130 assign_stack_local uses frame_pointer_rtx when this is nonzero.
131 calls.c:emit_library_call_value_1 uses it to set up
132 post-instantiation libcalls. */
133 int virtuals_instantiated;
135 /* Nonzero if at least one trampoline has been created. */
136 int trampolines_created;
138 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
139 static GTY(()) int funcdef_no;
141 /* These variables hold pointers to functions to create and destroy
142 target specific, per-function data structures. */
143 struct machine_function * (*init_machine_status) (void);
145 /* The FUNCTION_DECL for an inline function currently being expanded. */
146 tree inline_function_decl;
148 /* The currently compiled function. */
149 struct function *cfun = 0;
151 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
152 static GTY(()) varray_type prologue;
153 static GTY(()) varray_type epilogue;
155 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
157 static GTY(()) varray_type sibcall_epilogue;
159 /* In order to evaluate some expressions, such as function calls returning
160 structures in memory, we need to temporarily allocate stack locations.
161 We record each allocated temporary in the following structure.
163 Associated with each temporary slot is a nesting level. When we pop up
164 one level, all temporaries associated with the previous level are freed.
165 Normally, all temporaries are freed after the execution of the statement
166 in which they were created. However, if we are inside a ({...}) grouping,
167 the result may be in a temporary and hence must be preserved. If the
168 result could be in a temporary, we preserve it if we can determine which
169 one it is in. If we cannot determine which temporary may contain the
170 result, all temporaries are preserved. A temporary is preserved by
171 pretending it was allocated at the previous nesting level.
173 Automatic variables are also assigned temporary slots, at the nesting
174 level where they are defined. They are marked a "kept" so that
175 free_temp_slots will not free them. */
177 struct temp_slot GTY(())
179 /* Points to next temporary slot. */
180 struct temp_slot *next;
181 /* The rtx to used to reference the slot. */
183 /* The rtx used to represent the address if not the address of the
184 slot above. May be an EXPR_LIST if multiple addresses exist. */
186 /* The alignment (in bits) of the slot. */
188 /* The size, in units, of the slot. */
190 /* The type of the object in the slot, or zero if it doesn't correspond
191 to a type. We use this to determine whether a slot can be reused.
192 It can be reused if objects of the type of the new slot will always
193 conflict with objects of the type of the old slot. */
195 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
197 /* Nonzero if this temporary is currently in use. */
199 /* Nonzero if this temporary has its address taken. */
201 /* Nesting level at which this slot is being used. */
203 /* Nonzero if this should survive a call to free_temp_slots. */
205 /* The offset of the slot from the frame_pointer, including extra space
206 for alignment. This info is for combine_temp_slots. */
207 HOST_WIDE_INT base_offset;
208 /* The size of the slot, including extra space for alignment. This
209 info is for combine_temp_slots. */
210 HOST_WIDE_INT full_size;
213 /* This structure is used to record MEMs or pseudos used to replace VAR, any
214 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
215 maintain this list in case two operands of an insn were required to match;
216 in that case we must ensure we use the same replacement. */
218 struct fixup_replacement GTY(())
222 struct fixup_replacement *next;
225 struct insns_for_mem_entry
229 /* These are the INSNs which reference the MEM. */
233 /* Forward declarations. */
235 static rtx assign_stack_local_1 (enum machine_mode, HOST_WIDE_INT, int,
237 static struct temp_slot *find_temp_slot_from_address (rtx);
238 static void put_reg_into_stack (struct function *, rtx, tree, enum machine_mode,
239 enum machine_mode, int, unsigned int, int, htab_t);
240 static void schedule_fixup_var_refs (struct function *, rtx, tree, enum machine_mode,
242 static void fixup_var_refs (rtx, enum machine_mode, int, rtx, htab_t);
243 static struct fixup_replacement
244 *find_fixup_replacement (struct fixup_replacement **, rtx);
245 static void fixup_var_refs_insns (rtx, rtx, enum machine_mode, int, int, rtx);
246 static void fixup_var_refs_insns_with_hash (htab_t, rtx, enum machine_mode, int, rtx);
247 static void fixup_var_refs_insn (rtx, rtx, enum machine_mode, int, int, rtx);
248 static void fixup_var_refs_1 (rtx, enum machine_mode, rtx *, rtx,
249 struct fixup_replacement **, rtx);
250 static rtx fixup_memory_subreg (rtx, rtx, enum machine_mode, int);
251 static rtx walk_fixup_memory_subreg (rtx, rtx, enum machine_mode, int);
252 static rtx fixup_stack_1 (rtx, rtx);
253 static void optimize_bit_field (rtx, rtx, rtx *);
254 static void instantiate_decls (tree, int);
255 static void instantiate_decls_1 (tree, int);
256 static void instantiate_decl (rtx, HOST_WIDE_INT, int);
257 static rtx instantiate_new_reg (rtx, HOST_WIDE_INT *);
258 static int instantiate_virtual_regs_1 (rtx *, rtx, int);
259 static void delete_handlers (void);
260 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
261 static void pad_below (struct args_size *, enum machine_mode, tree);
262 static rtx round_trampoline_addr (rtx);
263 static rtx adjust_trampoline_addr (rtx);
264 static tree *identify_blocks_1 (rtx, tree *, tree *, tree *);
265 static void reorder_blocks_0 (tree);
266 static void reorder_blocks_1 (rtx, tree, varray_type *);
267 static void reorder_fix_fragments (tree);
268 static tree blocks_nreverse (tree);
269 static int all_blocks (tree, tree *);
270 static tree *get_block_vector (tree, int *);
271 extern tree debug_find_var_in_block_tree (tree, tree);
272 /* We always define `record_insns' even if its not used so that we
273 can always export `prologue_epilogue_contains'. */
274 static void record_insns (rtx, varray_type *) ATTRIBUTE_UNUSED;
275 static int contains (rtx, varray_type);
277 static void emit_return_into_block (basic_block, rtx);
279 static void put_addressof_into_stack (rtx, htab_t);
280 static bool purge_addressof_1 (rtx *, rtx, int, int, int, htab_t);
281 static void purge_single_hard_subreg_set (rtx);
282 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
283 static rtx keep_stack_depressed (rtx);
285 static int is_addressof (rtx *, void *);
286 static hashval_t insns_for_mem_hash (const void *);
287 static int insns_for_mem_comp (const void *, const void *);
288 static int insns_for_mem_walk (rtx *, void *);
289 static void compute_insns_for_mem (rtx, rtx, htab_t);
290 static void prepare_function_start (tree);
291 static void do_clobber_return_reg (rtx, void *);
292 static void do_use_return_reg (rtx, void *);
293 static void instantiate_virtual_regs_lossage (rtx);
294 static tree split_complex_args (tree);
295 static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED;
297 /* Pointer to chain of `struct function' for containing functions. */
298 struct function *outer_function_chain;
300 /* List of insns that were postponed by purge_addressof_1. */
301 static rtx postponed_insns;
303 /* Given a function decl for a containing function,
304 return the `struct function' for it. */
307 find_function_data (tree decl)
311 for (p = outer_function_chain; p; p = p->outer)
318 /* Save the current context for compilation of a nested function.
319 This is called from language-specific code. The caller should use
320 the enter_nested langhook to save any language-specific state,
321 since this function knows only about language-independent
325 push_function_context_to (tree context)
331 if (context == current_function_decl)
332 cfun->contains_functions = 1;
335 struct function *containing = find_function_data (context);
336 containing->contains_functions = 1;
341 init_dummy_function_start ();
344 p->outer = outer_function_chain;
345 outer_function_chain = p;
346 p->fixup_var_refs_queue = 0;
348 (*lang_hooks.function.enter_nested) (p);
354 push_function_context (void)
356 push_function_context_to (current_function_decl);
359 /* Restore the last saved context, at the end of a nested function.
360 This function is called from language-specific code. */
363 pop_function_context_from (tree context ATTRIBUTE_UNUSED)
365 struct function *p = outer_function_chain;
366 struct var_refs_queue *queue;
369 outer_function_chain = p->outer;
371 current_function_decl = p->decl;
374 restore_emit_status (p);
376 (*lang_hooks.function.leave_nested) (p);
378 /* Finish doing put_var_into_stack for any of our variables which became
379 addressable during the nested function. If only one entry has to be
380 fixed up, just do that one. Otherwise, first make a list of MEMs that
381 are not to be unshared. */
382 if (p->fixup_var_refs_queue == 0)
384 else if (p->fixup_var_refs_queue->next == 0)
385 fixup_var_refs (p->fixup_var_refs_queue->modified,
386 p->fixup_var_refs_queue->promoted_mode,
387 p->fixup_var_refs_queue->unsignedp,
388 p->fixup_var_refs_queue->modified, 0);
393 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
394 list = gen_rtx_EXPR_LIST (VOIDmode, queue->modified, list);
396 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
397 fixup_var_refs (queue->modified, queue->promoted_mode,
398 queue->unsignedp, list, 0);
402 p->fixup_var_refs_queue = 0;
404 /* Reset variables that have known state during rtx generation. */
405 rtx_equal_function_value_matters = 1;
406 virtuals_instantiated = 0;
407 generating_concat_p = 1;
411 pop_function_context (void)
413 pop_function_context_from (current_function_decl);
416 /* Clear out all parts of the state in F that can safely be discarded
417 after the function has been parsed, but not compiled, to let
418 garbage collection reclaim the memory. */
421 free_after_parsing (struct function *f)
423 /* f->expr->forced_labels is used by code generation. */
424 /* f->emit->regno_reg_rtx is used by code generation. */
425 /* f->varasm is used by code generation. */
426 /* f->eh->eh_return_stub_label is used by code generation. */
428 (*lang_hooks.function.final) (f);
432 /* Clear out all parts of the state in F that can safely be discarded
433 after the function has been compiled, to let garbage collection
434 reclaim the memory. */
437 free_after_compilation (struct function *f)
445 f->x_temp_slots = NULL;
446 f->arg_offset_rtx = NULL;
447 f->return_rtx = NULL;
448 f->internal_arg_pointer = NULL;
449 f->x_nonlocal_labels = NULL;
450 f->x_nonlocal_goto_handler_slots = NULL;
451 f->x_nonlocal_goto_handler_labels = NULL;
452 f->x_nonlocal_goto_stack_level = NULL;
453 f->x_cleanup_label = NULL;
454 f->x_return_label = NULL;
455 f->x_naked_return_label = NULL;
456 f->computed_goto_common_label = NULL;
457 f->computed_goto_common_reg = NULL;
458 f->x_save_expr_regs = NULL;
459 f->x_stack_slot_list = NULL;
460 f->x_rtl_expr_chain = NULL;
461 f->x_tail_recursion_label = NULL;
462 f->x_tail_recursion_reentry = NULL;
463 f->x_arg_pointer_save_area = NULL;
464 f->x_clobber_return_insn = NULL;
465 f->x_context_display = NULL;
466 f->x_trampoline_list = NULL;
467 f->x_parm_birth_insn = NULL;
468 f->x_last_parm_insn = NULL;
469 f->x_parm_reg_stack_loc = NULL;
470 f->fixup_var_refs_queue = NULL;
471 f->original_arg_vector = NULL;
472 f->original_decl_initial = NULL;
473 f->inl_last_parm_insn = NULL;
474 f->epilogue_delay_list = NULL;
477 /* Allocate fixed slots in the stack frame of the current function. */
479 /* Return size needed for stack frame based on slots so far allocated in
481 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
482 the caller may have to do that. */
485 get_func_frame_size (struct function *f)
487 #ifdef FRAME_GROWS_DOWNWARD
488 return -f->x_frame_offset;
490 return f->x_frame_offset;
494 /* Return size needed for stack frame based on slots so far allocated.
495 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
496 the caller may have to do that. */
498 get_frame_size (void)
500 return get_func_frame_size (cfun);
503 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
504 with machine mode MODE.
506 ALIGN controls the amount of alignment for the address of the slot:
507 0 means according to MODE,
508 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
509 positive specifies alignment boundary in bits.
511 We do not round to stack_boundary here.
513 FUNCTION specifies the function to allocate in. */
516 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size, int align,
517 struct function *function)
520 int bigend_correction = 0;
522 int frame_off, frame_alignment, frame_phase;
529 alignment = BIGGEST_ALIGNMENT;
531 alignment = GET_MODE_ALIGNMENT (mode);
533 /* Allow the target to (possibly) increase the alignment of this
535 type = (*lang_hooks.types.type_for_mode) (mode, 0);
537 alignment = LOCAL_ALIGNMENT (type, alignment);
539 alignment /= BITS_PER_UNIT;
541 else if (align == -1)
543 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
544 size = CEIL_ROUND (size, alignment);
547 alignment = align / BITS_PER_UNIT;
549 #ifdef FRAME_GROWS_DOWNWARD
550 function->x_frame_offset -= size;
553 /* Ignore alignment we can't do with expected alignment of the boundary. */
554 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
555 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
557 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
558 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
560 /* Calculate how many bytes the start of local variables is off from
562 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
563 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
564 frame_phase = frame_off ? frame_alignment - frame_off : 0;
566 /* Round the frame offset to the specified alignment. The default is
567 to always honor requests to align the stack but a port may choose to
568 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
569 if (STACK_ALIGNMENT_NEEDED
573 /* We must be careful here, since FRAME_OFFSET might be negative and
574 division with a negative dividend isn't as well defined as we might
575 like. So we instead assume that ALIGNMENT is a power of two and
576 use logical operations which are unambiguous. */
577 #ifdef FRAME_GROWS_DOWNWARD
578 function->x_frame_offset
579 = (FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment)
582 function->x_frame_offset
583 = (CEIL_ROUND (function->x_frame_offset - frame_phase, alignment)
588 /* On a big-endian machine, if we are allocating more space than we will use,
589 use the least significant bytes of those that are allocated. */
590 if (BYTES_BIG_ENDIAN && mode != BLKmode)
591 bigend_correction = size - GET_MODE_SIZE (mode);
593 /* If we have already instantiated virtual registers, return the actual
594 address relative to the frame pointer. */
595 if (function == cfun && virtuals_instantiated)
596 addr = plus_constant (frame_pointer_rtx,
598 (frame_offset + bigend_correction
599 + STARTING_FRAME_OFFSET, Pmode));
601 addr = plus_constant (virtual_stack_vars_rtx,
603 (function->x_frame_offset + bigend_correction,
606 #ifndef FRAME_GROWS_DOWNWARD
607 function->x_frame_offset += size;
610 x = gen_rtx_MEM (mode, addr);
612 function->x_stack_slot_list
613 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
618 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
622 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
624 return assign_stack_local_1 (mode, size, align, cfun);
627 /* Allocate a temporary stack slot and record it for possible later
630 MODE is the machine mode to be given to the returned rtx.
632 SIZE is the size in units of the space required. We do no rounding here
633 since assign_stack_local will do any required rounding.
635 KEEP is 1 if this slot is to be retained after a call to
636 free_temp_slots. Automatic variables for a block are allocated
637 with this flag. KEEP is 2 if we allocate a longer term temporary,
638 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
639 if we are to allocate something at an inner level to be treated as
640 a variable in the block (e.g., a SAVE_EXPR).
642 TYPE is the type that will be used for the stack slot. */
645 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size, int keep,
649 struct temp_slot *p, *best_p = 0;
652 /* If SIZE is -1 it means that somebody tried to allocate a temporary
653 of a variable size. */
658 align = BIGGEST_ALIGNMENT;
660 align = GET_MODE_ALIGNMENT (mode);
663 type = (*lang_hooks.types.type_for_mode) (mode, 0);
666 align = LOCAL_ALIGNMENT (type, align);
668 /* Try to find an available, already-allocated temporary of the proper
669 mode which meets the size and alignment requirements. Choose the
670 smallest one with the closest alignment. */
671 for (p = temp_slots; p; p = p->next)
672 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
674 && objects_must_conflict_p (p->type, type)
675 && (best_p == 0 || best_p->size > p->size
676 || (best_p->size == p->size && best_p->align > p->align)))
678 if (p->align == align && p->size == size)
686 /* Make our best, if any, the one to use. */
689 /* If there are enough aligned bytes left over, make them into a new
690 temp_slot so that the extra bytes don't get wasted. Do this only
691 for BLKmode slots, so that we can be sure of the alignment. */
692 if (GET_MODE (best_p->slot) == BLKmode)
694 int alignment = best_p->align / BITS_PER_UNIT;
695 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
697 if (best_p->size - rounded_size >= alignment)
699 p = ggc_alloc (sizeof (struct temp_slot));
700 p->in_use = p->addr_taken = 0;
701 p->size = best_p->size - rounded_size;
702 p->base_offset = best_p->base_offset + rounded_size;
703 p->full_size = best_p->full_size - rounded_size;
704 p->slot = gen_rtx_MEM (BLKmode,
705 plus_constant (XEXP (best_p->slot, 0),
707 p->align = best_p->align;
710 p->type = best_p->type;
711 p->next = temp_slots;
714 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
717 best_p->size = rounded_size;
718 best_p->full_size = rounded_size;
725 /* If we still didn't find one, make a new temporary. */
728 HOST_WIDE_INT frame_offset_old = frame_offset;
730 p = ggc_alloc (sizeof (struct temp_slot));
732 /* We are passing an explicit alignment request to assign_stack_local.
733 One side effect of that is assign_stack_local will not round SIZE
734 to ensure the frame offset remains suitably aligned.
736 So for requests which depended on the rounding of SIZE, we go ahead
737 and round it now. We also make sure ALIGNMENT is at least
738 BIGGEST_ALIGNMENT. */
739 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
741 p->slot = assign_stack_local (mode,
743 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
749 /* The following slot size computation is necessary because we don't
750 know the actual size of the temporary slot until assign_stack_local
751 has performed all the frame alignment and size rounding for the
752 requested temporary. Note that extra space added for alignment
753 can be either above or below this stack slot depending on which
754 way the frame grows. We include the extra space if and only if it
755 is above this slot. */
756 #ifdef FRAME_GROWS_DOWNWARD
757 p->size = frame_offset_old - frame_offset;
762 /* Now define the fields used by combine_temp_slots. */
763 #ifdef FRAME_GROWS_DOWNWARD
764 p->base_offset = frame_offset;
765 p->full_size = frame_offset_old - frame_offset;
767 p->base_offset = frame_offset_old;
768 p->full_size = frame_offset - frame_offset_old;
771 p->next = temp_slots;
777 p->rtl_expr = seq_rtl_expr;
782 p->level = target_temp_slot_level;
787 p->level = var_temp_slot_level;
792 p->level = temp_slot_level;
797 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
798 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
799 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
801 /* If we know the alias set for the memory that will be used, use
802 it. If there's no TYPE, then we don't know anything about the
803 alias set for the memory. */
804 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
805 set_mem_align (slot, align);
807 /* If a type is specified, set the relevant flags. */
810 RTX_UNCHANGING_P (slot) = (lang_hooks.honor_readonly
811 && TYPE_READONLY (type));
812 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
813 MEM_SET_IN_STRUCT_P (slot, AGGREGATE_TYPE_P (type));
819 /* Allocate a temporary stack slot and record it for possible later
820 reuse. First three arguments are same as in preceding function. */
823 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
825 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
828 /* Assign a temporary.
829 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
830 and so that should be used in error messages. In either case, we
831 allocate of the given type.
832 KEEP is as for assign_stack_temp.
833 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
834 it is 0 if a register is OK.
835 DONT_PROMOTE is 1 if we should not promote values in register
839 assign_temp (tree type_or_decl, int keep, int memory_required,
840 int dont_promote ATTRIBUTE_UNUSED)
843 enum machine_mode mode;
844 #ifndef PROMOTE_FOR_CALL_ONLY
848 if (DECL_P (type_or_decl))
849 decl = type_or_decl, type = TREE_TYPE (decl);
851 decl = NULL, type = type_or_decl;
853 mode = TYPE_MODE (type);
854 #ifndef PROMOTE_FOR_CALL_ONLY
855 unsignedp = TREE_UNSIGNED (type);
858 if (mode == BLKmode || memory_required)
860 HOST_WIDE_INT size = int_size_in_bytes (type);
863 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
864 problems with allocating the stack space. */
868 /* Unfortunately, we don't yet know how to allocate variable-sized
869 temporaries. However, sometimes we have a fixed upper limit on
870 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
871 instead. This is the case for Chill variable-sized strings. */
872 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
873 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
874 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
875 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
877 /* The size of the temporary may be too large to fit into an integer. */
878 /* ??? Not sure this should happen except for user silliness, so limit
879 this to things that aren't compiler-generated temporaries. The
880 rest of the time we'll abort in assign_stack_temp_for_type. */
881 if (decl && size == -1
882 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
884 error ("%Jsize of variable '%D' is too large", decl, decl);
888 tmp = assign_stack_temp_for_type (mode, size, keep, type);
892 #ifndef PROMOTE_FOR_CALL_ONLY
894 mode = promote_mode (type, mode, &unsignedp, 0);
897 return gen_reg_rtx (mode);
900 /* Combine temporary stack slots which are adjacent on the stack.
902 This allows for better use of already allocated stack space. This is only
903 done for BLKmode slots because we can be sure that we won't have alignment
904 problems in this case. */
907 combine_temp_slots (void)
909 struct temp_slot *p, *q;
910 struct temp_slot *prev_p, *prev_q;
913 /* We can't combine slots, because the information about which slot
914 is in which alias set will be lost. */
915 if (flag_strict_aliasing)
918 /* If there are a lot of temp slots, don't do anything unless
919 high levels of optimization. */
920 if (! flag_expensive_optimizations)
921 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
922 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
925 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
929 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
930 for (q = p->next, prev_q = p; q; q = prev_q->next)
933 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
935 if (p->base_offset + p->full_size == q->base_offset)
937 /* Q comes after P; combine Q into P. */
939 p->full_size += q->full_size;
942 else if (q->base_offset + q->full_size == p->base_offset)
944 /* P comes after Q; combine P into Q. */
946 q->full_size += p->full_size;
951 /* Either delete Q or advance past it. */
953 prev_q->next = q->next;
957 /* Either delete P or advance past it. */
961 prev_p->next = p->next;
963 temp_slots = p->next;
970 /* Find the temp slot corresponding to the object at address X. */
972 static struct temp_slot *
973 find_temp_slot_from_address (rtx x)
978 for (p = temp_slots; p; p = p->next)
983 else if (XEXP (p->slot, 0) == x
985 || (GET_CODE (x) == PLUS
986 && XEXP (x, 0) == virtual_stack_vars_rtx
987 && GET_CODE (XEXP (x, 1)) == CONST_INT
988 && INTVAL (XEXP (x, 1)) >= p->base_offset
989 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
992 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
993 for (next = p->address; next; next = XEXP (next, 1))
994 if (XEXP (next, 0) == x)
998 /* If we have a sum involving a register, see if it points to a temp
1000 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
1001 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
1003 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
1004 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1010 /* Indicate that NEW is an alternate way of referring to the temp slot
1011 that previously was known by OLD. */
1014 update_temp_slot_address (rtx old, rtx new)
1016 struct temp_slot *p;
1018 if (rtx_equal_p (old, new))
1021 p = find_temp_slot_from_address (old);
1023 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1024 is a register, see if one operand of the PLUS is a temporary
1025 location. If so, NEW points into it. Otherwise, if both OLD and
1026 NEW are a PLUS and if there is a register in common between them.
1027 If so, try a recursive call on those values. */
1030 if (GET_CODE (old) != PLUS)
1033 if (GET_CODE (new) == REG)
1035 update_temp_slot_address (XEXP (old, 0), new);
1036 update_temp_slot_address (XEXP (old, 1), new);
1039 else if (GET_CODE (new) != PLUS)
1042 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1043 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1044 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1045 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1046 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1047 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1048 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1049 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1054 /* Otherwise add an alias for the temp's address. */
1055 else if (p->address == 0)
1059 if (GET_CODE (p->address) != EXPR_LIST)
1060 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1062 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1066 /* If X could be a reference to a temporary slot, mark the fact that its
1067 address was taken. */
1070 mark_temp_addr_taken (rtx x)
1072 struct temp_slot *p;
1077 /* If X is not in memory or is at a constant address, it cannot be in
1078 a temporary slot. */
1079 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1082 p = find_temp_slot_from_address (XEXP (x, 0));
1087 /* If X could be a reference to a temporary slot, mark that slot as
1088 belonging to the to one level higher than the current level. If X
1089 matched one of our slots, just mark that one. Otherwise, we can't
1090 easily predict which it is, so upgrade all of them. Kept slots
1091 need not be touched.
1093 This is called when an ({...}) construct occurs and a statement
1094 returns a value in memory. */
1097 preserve_temp_slots (rtx x)
1099 struct temp_slot *p = 0;
1101 /* If there is no result, we still might have some objects whose address
1102 were taken, so we need to make sure they stay around. */
1105 for (p = temp_slots; p; p = p->next)
1106 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1112 /* If X is a register that is being used as a pointer, see if we have
1113 a temporary slot we know it points to. To be consistent with
1114 the code below, we really should preserve all non-kept slots
1115 if we can't find a match, but that seems to be much too costly. */
1116 if (GET_CODE (x) == REG && REG_POINTER (x))
1117 p = find_temp_slot_from_address (x);
1119 /* If X is not in memory or is at a constant address, it cannot be in
1120 a temporary slot, but it can contain something whose address was
1122 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1124 for (p = temp_slots; p; p = p->next)
1125 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1131 /* First see if we can find a match. */
1133 p = find_temp_slot_from_address (XEXP (x, 0));
1137 /* Move everything at our level whose address was taken to our new
1138 level in case we used its address. */
1139 struct temp_slot *q;
1141 if (p->level == temp_slot_level)
1143 for (q = temp_slots; q; q = q->next)
1144 if (q != p && q->addr_taken && q->level == p->level)
1153 /* Otherwise, preserve all non-kept slots at this level. */
1154 for (p = temp_slots; p; p = p->next)
1155 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1159 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1160 with that RTL_EXPR, promote it into a temporary slot at the present
1161 level so it will not be freed when we free slots made in the
1165 preserve_rtl_expr_result (rtx x)
1167 struct temp_slot *p;
1169 /* If X is not in memory or is at a constant address, it cannot be in
1170 a temporary slot. */
1171 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1174 /* If we can find a match, move it to our level unless it is already at
1176 p = find_temp_slot_from_address (XEXP (x, 0));
1179 p->level = MIN (p->level, temp_slot_level);
1186 /* Free all temporaries used so far. This is normally called at the end
1187 of generating code for a statement. Don't free any temporaries
1188 currently in use for an RTL_EXPR that hasn't yet been emitted.
1189 We could eventually do better than this since it can be reused while
1190 generating the same RTL_EXPR, but this is complex and probably not
1194 free_temp_slots (void)
1196 struct temp_slot *p;
1198 for (p = temp_slots; p; p = p->next)
1199 if (p->in_use && p->level == temp_slot_level && ! p->keep
1200 && p->rtl_expr == 0)
1203 combine_temp_slots ();
1206 /* Free all temporary slots used in T, an RTL_EXPR node. */
1209 free_temps_for_rtl_expr (tree t)
1211 struct temp_slot *p;
1213 for (p = temp_slots; p; p = p->next)
1214 if (p->rtl_expr == t)
1216 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1217 needs to be preserved. This can happen if a temporary in
1218 the RTL_EXPR was addressed; preserve_temp_slots will move
1219 the temporary into a higher level. */
1220 if (temp_slot_level <= p->level)
1223 p->rtl_expr = NULL_TREE;
1226 combine_temp_slots ();
1229 /* Mark all temporaries ever allocated in this function as not suitable
1230 for reuse until the current level is exited. */
1233 mark_all_temps_used (void)
1235 struct temp_slot *p;
1237 for (p = temp_slots; p; p = p->next)
1239 p->in_use = p->keep = 1;
1240 p->level = MIN (p->level, temp_slot_level);
1244 /* Push deeper into the nesting level for stack temporaries. */
1247 push_temp_slots (void)
1252 /* Pop a temporary nesting level. All slots in use in the current level
1256 pop_temp_slots (void)
1258 struct temp_slot *p;
1260 for (p = temp_slots; p; p = p->next)
1261 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1264 combine_temp_slots ();
1269 /* Initialize temporary slots. */
1272 init_temp_slots (void)
1274 /* We have not allocated any temporaries yet. */
1276 temp_slot_level = 0;
1277 var_temp_slot_level = 0;
1278 target_temp_slot_level = 0;
1281 /* Retroactively move an auto variable from a register to a stack
1282 slot. This is done when an address-reference to the variable is
1283 seen. If RESCAN is true, all previously emitted instructions are
1284 examined and modified to handle the fact that DECL is now
1288 put_var_into_stack (tree decl, int rescan)
1291 enum machine_mode promoted_mode, decl_mode;
1292 struct function *function = 0;
1294 int can_use_addressof;
1295 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1296 int usedp = (TREE_USED (decl)
1297 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1299 context = decl_function_context (decl);
1301 /* Get the current rtl used for this object and its original mode. */
1302 reg = (TREE_CODE (decl) == SAVE_EXPR
1303 ? SAVE_EXPR_RTL (decl)
1304 : DECL_RTL_IF_SET (decl));
1306 /* No need to do anything if decl has no rtx yet
1307 since in that case caller is setting TREE_ADDRESSABLE
1308 and a stack slot will be assigned when the rtl is made. */
1312 /* Get the declared mode for this object. */
1313 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1314 : DECL_MODE (decl));
1315 /* Get the mode it's actually stored in. */
1316 promoted_mode = GET_MODE (reg);
1318 /* If this variable comes from an outer function, find that
1319 function's saved context. Don't use find_function_data here,
1320 because it might not be in any active function.
1321 FIXME: Is that really supposed to happen?
1322 It does in ObjC at least. */
1323 if (context != current_function_decl && context != inline_function_decl)
1324 for (function = outer_function_chain; function; function = function->outer)
1325 if (function->decl == context)
1328 /* If this is a variable-sized object or a structure passed by invisible
1329 reference, with a pseudo to address it, put that pseudo into the stack
1330 if the var is non-local. */
1331 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1332 && GET_CODE (reg) == MEM
1333 && GET_CODE (XEXP (reg, 0)) == REG
1334 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1336 reg = XEXP (reg, 0);
1337 decl_mode = promoted_mode = GET_MODE (reg);
1340 /* If this variable lives in the current function and we don't need to put it
1341 in the stack for the sake of setjmp or the non-locality, try to keep it in
1342 a register until we know we actually need the address. */
1345 && ! (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl))
1347 /* FIXME make it work for promoted modes too */
1348 && decl_mode == promoted_mode
1349 #ifdef NON_SAVING_SETJMP
1350 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1354 /* If we can't use ADDRESSOF, make sure we see through one we already
1356 if (! can_use_addressof && GET_CODE (reg) == MEM
1357 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1358 reg = XEXP (XEXP (reg, 0), 0);
1360 /* Now we should have a value that resides in one or more pseudo regs. */
1362 if (GET_CODE (reg) == REG)
1364 if (can_use_addressof)
1365 gen_mem_addressof (reg, decl, rescan);
1367 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1368 decl_mode, volatilep, 0, usedp, 0);
1370 else if (GET_CODE (reg) == CONCAT)
1372 /* A CONCAT contains two pseudos; put them both in the stack.
1373 We do it so they end up consecutive.
1374 We fixup references to the parts only after we fixup references
1375 to the whole CONCAT, lest we do double fixups for the latter
1377 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1378 tree part_type = (*lang_hooks.types.type_for_mode) (part_mode, 0);
1379 rtx lopart = XEXP (reg, 0);
1380 rtx hipart = XEXP (reg, 1);
1381 #ifdef FRAME_GROWS_DOWNWARD
1382 /* Since part 0 should have a lower address, do it second. */
1383 put_reg_into_stack (function, hipart, part_type, part_mode,
1384 part_mode, volatilep, 0, 0, 0);
1385 put_reg_into_stack (function, lopart, part_type, part_mode,
1386 part_mode, volatilep, 0, 0, 0);
1388 put_reg_into_stack (function, lopart, part_type, part_mode,
1389 part_mode, volatilep, 0, 0, 0);
1390 put_reg_into_stack (function, hipart, part_type, part_mode,
1391 part_mode, volatilep, 0, 0, 0);
1394 /* Change the CONCAT into a combined MEM for both parts. */
1395 PUT_CODE (reg, MEM);
1396 MEM_ATTRS (reg) = 0;
1398 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1399 already computed alias sets. Here we want to re-generate. */
1401 SET_DECL_RTL (decl, NULL);
1402 set_mem_attributes (reg, decl, 1);
1404 SET_DECL_RTL (decl, reg);
1406 /* The two parts are in memory order already.
1407 Use the lower parts address as ours. */
1408 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1409 /* Prevent sharing of rtl that might lose. */
1410 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1411 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1412 if (usedp && rescan)
1414 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1416 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1417 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1424 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1425 into the stack frame of FUNCTION (0 means the current function).
1426 DECL_MODE is the machine mode of the user-level data type.
1427 PROMOTED_MODE is the machine mode of the register.
1428 VOLATILE_P is nonzero if this is for a "volatile" decl.
1429 USED_P is nonzero if this reg might have already been used in an insn. */
1432 put_reg_into_stack (struct function *function, rtx reg, tree type,
1433 enum machine_mode promoted_mode, enum machine_mode decl_mode,
1434 int volatile_p, unsigned int original_regno, int used_p, htab_t ht)
1436 struct function *func = function ? function : cfun;
1438 unsigned int regno = original_regno;
1441 regno = REGNO (reg);
1443 if (regno < func->x_max_parm_reg)
1444 new = func->x_parm_reg_stack_loc[regno];
1447 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1449 PUT_CODE (reg, MEM);
1450 PUT_MODE (reg, decl_mode);
1451 XEXP (reg, 0) = XEXP (new, 0);
1452 MEM_ATTRS (reg) = 0;
1453 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1454 MEM_VOLATILE_P (reg) = volatile_p;
1456 /* If this is a memory ref that contains aggregate components,
1457 mark it as such for cse and loop optimize. If we are reusing a
1458 previously generated stack slot, then we need to copy the bit in
1459 case it was set for other reasons. For instance, it is set for
1460 __builtin_va_alist. */
1463 MEM_SET_IN_STRUCT_P (reg,
1464 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1465 set_mem_alias_set (reg, get_alias_set (type));
1469 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1472 /* Make sure that all refs to the variable, previously made
1473 when it was a register, are fixed up to be valid again.
1474 See function above for meaning of arguments. */
1477 schedule_fixup_var_refs (struct function *function, rtx reg, tree type,
1478 enum machine_mode promoted_mode, htab_t ht)
1480 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1484 struct var_refs_queue *temp;
1486 temp = ggc_alloc (sizeof (struct var_refs_queue));
1487 temp->modified = reg;
1488 temp->promoted_mode = promoted_mode;
1489 temp->unsignedp = unsigned_p;
1490 temp->next = function->fixup_var_refs_queue;
1491 function->fixup_var_refs_queue = temp;
1494 /* Variable is local; fix it up now. */
1495 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht);
1499 fixup_var_refs (rtx var, enum machine_mode promoted_mode, int unsignedp,
1500 rtx may_share, htab_t ht)
1503 rtx first_insn = get_insns ();
1504 struct sequence_stack *stack = seq_stack;
1505 tree rtl_exps = rtl_expr_chain;
1507 /* If there's a hash table, it must record all uses of VAR. */
1512 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp,
1517 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1518 stack == 0, may_share);
1520 /* Scan all pending sequences too. */
1521 for (; stack; stack = stack->next)
1523 push_to_full_sequence (stack->first, stack->last);
1524 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1525 stack->next != 0, may_share);
1526 /* Update remembered end of sequence
1527 in case we added an insn at the end. */
1528 stack->last = get_last_insn ();
1532 /* Scan all waiting RTL_EXPRs too. */
1533 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1535 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1536 if (seq != const0_rtx && seq != 0)
1538 push_to_sequence (seq);
1539 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1546 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1547 some part of an insn. Return a struct fixup_replacement whose OLD
1548 value is equal to X. Allocate a new structure if no such entry exists. */
1550 static struct fixup_replacement *
1551 find_fixup_replacement (struct fixup_replacement **replacements, rtx x)
1553 struct fixup_replacement *p;
1555 /* See if we have already replaced this. */
1556 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1561 p = xmalloc (sizeof (struct fixup_replacement));
1564 p->next = *replacements;
1571 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1572 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1573 for the current function. MAY_SHARE is either a MEM that is not
1574 to be unshared or a list of them. */
1577 fixup_var_refs_insns (rtx insn, rtx var, enum machine_mode promoted_mode,
1578 int unsignedp, int toplevel, rtx may_share)
1582 /* fixup_var_refs_insn might modify insn, so save its next
1584 rtx next = NEXT_INSN (insn);
1586 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1587 the three sequences they (potentially) contain, and process
1588 them recursively. The CALL_INSN itself is not interesting. */
1590 if (GET_CODE (insn) == CALL_INSN
1591 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1595 /* Look at the Normal call, sibling call and tail recursion
1596 sequences attached to the CALL_PLACEHOLDER. */
1597 for (i = 0; i < 3; i++)
1599 rtx seq = XEXP (PATTERN (insn), i);
1602 push_to_sequence (seq);
1603 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1605 XEXP (PATTERN (insn), i) = get_insns ();
1611 else if (INSN_P (insn))
1612 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel,
1619 /* Look up the insns which reference VAR in HT and fix them up. Other
1620 arguments are the same as fixup_var_refs_insns.
1622 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1623 because the hash table will point straight to the interesting insn
1624 (inside the CALL_PLACEHOLDER). */
1627 fixup_var_refs_insns_with_hash (htab_t ht, rtx var, enum machine_mode promoted_mode,
1628 int unsignedp, rtx may_share)
1630 struct insns_for_mem_entry tmp;
1631 struct insns_for_mem_entry *ime;
1635 ime = htab_find (ht, &tmp);
1636 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1))
1637 if (INSN_P (XEXP (insn_list, 0)))
1638 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode,
1639 unsignedp, 1, may_share);
1643 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1644 the insn under examination, VAR is the variable to fix up
1645 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1646 TOPLEVEL is nonzero if this is the main insn chain for this
1650 fixup_var_refs_insn (rtx insn, rtx var, enum machine_mode promoted_mode,
1651 int unsignedp, int toplevel, rtx no_share)
1654 rtx set, prev, prev_set;
1657 /* Remember the notes in case we delete the insn. */
1658 note = REG_NOTES (insn);
1660 /* If this is a CLOBBER of VAR, delete it.
1662 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1663 and REG_RETVAL notes too. */
1664 if (GET_CODE (PATTERN (insn)) == CLOBBER
1665 && (XEXP (PATTERN (insn), 0) == var
1666 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1667 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1668 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1670 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1671 /* The REG_LIBCALL note will go away since we are going to
1672 turn INSN into a NOTE, so just delete the
1673 corresponding REG_RETVAL note. */
1674 remove_note (XEXP (note, 0),
1675 find_reg_note (XEXP (note, 0), REG_RETVAL,
1681 /* The insn to load VAR from a home in the arglist
1682 is now a no-op. When we see it, just delete it.
1683 Similarly if this is storing VAR from a register from which
1684 it was loaded in the previous insn. This will occur
1685 when an ADDRESSOF was made for an arglist slot. */
1687 && (set = single_set (insn)) != 0
1688 && SET_DEST (set) == var
1689 /* If this represents the result of an insn group,
1690 don't delete the insn. */
1691 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1692 && (rtx_equal_p (SET_SRC (set), var)
1693 || (GET_CODE (SET_SRC (set)) == REG
1694 && (prev = prev_nonnote_insn (insn)) != 0
1695 && (prev_set = single_set (prev)) != 0
1696 && SET_DEST (prev_set) == SET_SRC (set)
1697 && rtx_equal_p (SET_SRC (prev_set), var))))
1703 struct fixup_replacement *replacements = 0;
1704 rtx next_insn = NEXT_INSN (insn);
1706 if (SMALL_REGISTER_CLASSES)
1708 /* If the insn that copies the results of a CALL_INSN
1709 into a pseudo now references VAR, we have to use an
1710 intermediate pseudo since we want the life of the
1711 return value register to be only a single insn.
1713 If we don't use an intermediate pseudo, such things as
1714 address computations to make the address of VAR valid
1715 if it is not can be placed between the CALL_INSN and INSN.
1717 To make sure this doesn't happen, we record the destination
1718 of the CALL_INSN and see if the next insn uses both that
1721 if (call_dest != 0 && GET_CODE (insn) == INSN
1722 && reg_mentioned_p (var, PATTERN (insn))
1723 && reg_mentioned_p (call_dest, PATTERN (insn)))
1725 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1727 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1729 PATTERN (insn) = replace_rtx (PATTERN (insn),
1733 if (GET_CODE (insn) == CALL_INSN
1734 && GET_CODE (PATTERN (insn)) == SET)
1735 call_dest = SET_DEST (PATTERN (insn));
1736 else if (GET_CODE (insn) == CALL_INSN
1737 && GET_CODE (PATTERN (insn)) == PARALLEL
1738 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1739 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1744 /* See if we have to do anything to INSN now that VAR is in
1745 memory. If it needs to be loaded into a pseudo, use a single
1746 pseudo for the entire insn in case there is a MATCH_DUP
1747 between two operands. We pass a pointer to the head of
1748 a list of struct fixup_replacements. If fixup_var_refs_1
1749 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1750 it will record them in this list.
1752 If it allocated a pseudo for any replacement, we copy into
1755 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1756 &replacements, no_share);
1758 /* If this is last_parm_insn, and any instructions were output
1759 after it to fix it up, then we must set last_parm_insn to
1760 the last such instruction emitted. */
1761 if (insn == last_parm_insn)
1762 last_parm_insn = PREV_INSN (next_insn);
1764 while (replacements)
1766 struct fixup_replacement *next;
1768 if (GET_CODE (replacements->new) == REG)
1773 /* OLD might be a (subreg (mem)). */
1774 if (GET_CODE (replacements->old) == SUBREG)
1776 = fixup_memory_subreg (replacements->old, insn,
1780 = fixup_stack_1 (replacements->old, insn);
1782 insert_before = insn;
1784 /* If we are changing the mode, do a conversion.
1785 This might be wasteful, but combine.c will
1786 eliminate much of the waste. */
1788 if (GET_MODE (replacements->new)
1789 != GET_MODE (replacements->old))
1792 convert_move (replacements->new,
1793 replacements->old, unsignedp);
1798 seq = gen_move_insn (replacements->new,
1801 emit_insn_before (seq, insert_before);
1804 next = replacements->next;
1805 free (replacements);
1806 replacements = next;
1810 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1811 But don't touch other insns referred to by reg-notes;
1812 we will get them elsewhere. */
1815 if (GET_CODE (note) != INSN_LIST)
1817 = walk_fixup_memory_subreg (XEXP (note, 0), insn,
1819 note = XEXP (note, 1);
1823 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1824 See if the rtx expression at *LOC in INSN needs to be changed.
1826 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1827 contain a list of original rtx's and replacements. If we find that we need
1828 to modify this insn by replacing a memory reference with a pseudo or by
1829 making a new MEM to implement a SUBREG, we consult that list to see if
1830 we have already chosen a replacement. If none has already been allocated,
1831 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1832 or the SUBREG, as appropriate, to the pseudo. */
1835 fixup_var_refs_1 (rtx var, enum machine_mode promoted_mode, rtx *loc, rtx insn,
1836 struct fixup_replacement **replacements, rtx no_share)
1840 RTX_CODE code = GET_CODE (x);
1843 struct fixup_replacement *replacement;
1848 if (XEXP (x, 0) == var)
1850 /* Prevent sharing of rtl that might lose. */
1851 rtx sub = copy_rtx (XEXP (var, 0));
1853 if (! validate_change (insn, loc, sub, 0))
1855 rtx y = gen_reg_rtx (GET_MODE (sub));
1858 /* We should be able to replace with a register or all is lost.
1859 Note that we can't use validate_change to verify this, since
1860 we're not caring for replacing all dups simultaneously. */
1861 if (! validate_replace_rtx (*loc, y, insn))
1864 /* Careful! First try to recognize a direct move of the
1865 value, mimicking how things are done in gen_reload wrt
1866 PLUS. Consider what happens when insn is a conditional
1867 move instruction and addsi3 clobbers flags. */
1870 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1874 if (recog_memoized (new_insn) < 0)
1876 /* That failed. Fall back on force_operand and hope. */
1879 sub = force_operand (sub, y);
1881 emit_insn (gen_move_insn (y, sub));
1887 /* Don't separate setter from user. */
1888 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1889 insn = PREV_INSN (insn);
1892 emit_insn_before (seq, insn);
1900 /* If we already have a replacement, use it. Otherwise,
1901 try to fix up this address in case it is invalid. */
1903 replacement = find_fixup_replacement (replacements, var);
1904 if (replacement->new)
1906 *loc = replacement->new;
1910 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1912 /* Unless we are forcing memory to register or we changed the mode,
1913 we can leave things the way they are if the insn is valid. */
1915 INSN_CODE (insn) = -1;
1916 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1917 && recog_memoized (insn) >= 0)
1920 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1924 /* If X contains VAR, we need to unshare it here so that we update
1925 each occurrence separately. But all identical MEMs in one insn
1926 must be replaced with the same rtx because of the possibility of
1929 if (reg_mentioned_p (var, x))
1931 replacement = find_fixup_replacement (replacements, x);
1932 if (replacement->new == 0)
1933 replacement->new = copy_most_rtx (x, no_share);
1935 *loc = x = replacement->new;
1936 code = GET_CODE (x);
1953 /* Note that in some cases those types of expressions are altered
1954 by optimize_bit_field, and do not survive to get here. */
1955 if (XEXP (x, 0) == var
1956 || (GET_CODE (XEXP (x, 0)) == SUBREG
1957 && SUBREG_REG (XEXP (x, 0)) == var))
1959 /* Get TEM as a valid MEM in the mode presently in the insn.
1961 We don't worry about the possibility of MATCH_DUP here; it
1962 is highly unlikely and would be tricky to handle. */
1965 if (GET_CODE (tem) == SUBREG)
1967 if (GET_MODE_BITSIZE (GET_MODE (tem))
1968 > GET_MODE_BITSIZE (GET_MODE (var)))
1970 replacement = find_fixup_replacement (replacements, var);
1971 if (replacement->new == 0)
1972 replacement->new = gen_reg_rtx (GET_MODE (var));
1973 SUBREG_REG (tem) = replacement->new;
1975 /* The following code works only if we have a MEM, so we
1976 need to handle the subreg here. We directly substitute
1977 it assuming that a subreg must be OK here. We already
1978 scheduled a replacement to copy the mem into the
1984 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
1987 tem = fixup_stack_1 (tem, insn);
1989 /* Unless we want to load from memory, get TEM into the proper mode
1990 for an extract from memory. This can only be done if the
1991 extract is at a constant position and length. */
1993 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
1994 && GET_CODE (XEXP (x, 2)) == CONST_INT
1995 && ! mode_dependent_address_p (XEXP (tem, 0))
1996 && ! MEM_VOLATILE_P (tem))
1998 enum machine_mode wanted_mode = VOIDmode;
1999 enum machine_mode is_mode = GET_MODE (tem);
2000 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2002 if (GET_CODE (x) == ZERO_EXTRACT)
2004 enum machine_mode new_mode
2005 = mode_for_extraction (EP_extzv, 1);
2006 if (new_mode != MAX_MACHINE_MODE)
2007 wanted_mode = new_mode;
2009 else if (GET_CODE (x) == SIGN_EXTRACT)
2011 enum machine_mode new_mode
2012 = mode_for_extraction (EP_extv, 1);
2013 if (new_mode != MAX_MACHINE_MODE)
2014 wanted_mode = new_mode;
2017 /* If we have a narrower mode, we can do something. */
2018 if (wanted_mode != VOIDmode
2019 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2021 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2022 rtx old_pos = XEXP (x, 2);
2025 /* If the bytes and bits are counted differently, we
2026 must adjust the offset. */
2027 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2028 offset = (GET_MODE_SIZE (is_mode)
2029 - GET_MODE_SIZE (wanted_mode) - offset);
2031 pos %= GET_MODE_BITSIZE (wanted_mode);
2033 newmem = adjust_address_nv (tem, wanted_mode, offset);
2035 /* Make the change and see if the insn remains valid. */
2036 INSN_CODE (insn) = -1;
2037 XEXP (x, 0) = newmem;
2038 XEXP (x, 2) = GEN_INT (pos);
2040 if (recog_memoized (insn) >= 0)
2043 /* Otherwise, restore old position. XEXP (x, 0) will be
2045 XEXP (x, 2) = old_pos;
2049 /* If we get here, the bitfield extract insn can't accept a memory
2050 reference. Copy the input into a register. */
2052 tem1 = gen_reg_rtx (GET_MODE (tem));
2053 emit_insn_before (gen_move_insn (tem1, tem), insn);
2060 if (SUBREG_REG (x) == var)
2062 /* If this is a special SUBREG made because VAR was promoted
2063 from a wider mode, replace it with VAR and call ourself
2064 recursively, this time saying that the object previously
2065 had its current mode (by virtue of the SUBREG). */
2067 if (SUBREG_PROMOTED_VAR_P (x))
2070 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements,
2075 /* If this SUBREG makes VAR wider, it has become a paradoxical
2076 SUBREG with VAR in memory, but these aren't allowed at this
2077 stage of the compilation. So load VAR into a pseudo and take
2078 a SUBREG of that pseudo. */
2079 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2081 replacement = find_fixup_replacement (replacements, var);
2082 if (replacement->new == 0)
2083 replacement->new = gen_reg_rtx (promoted_mode);
2084 SUBREG_REG (x) = replacement->new;
2088 /* See if we have already found a replacement for this SUBREG.
2089 If so, use it. Otherwise, make a MEM and see if the insn
2090 is recognized. If not, or if we should force MEM into a register,
2091 make a pseudo for this SUBREG. */
2092 replacement = find_fixup_replacement (replacements, x);
2093 if (replacement->new)
2095 *loc = replacement->new;
2099 replacement->new = *loc = fixup_memory_subreg (x, insn,
2102 INSN_CODE (insn) = -1;
2103 if (! flag_force_mem && recog_memoized (insn) >= 0)
2106 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2112 /* First do special simplification of bit-field references. */
2113 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2114 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2115 optimize_bit_field (x, insn, 0);
2116 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2117 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2118 optimize_bit_field (x, insn, 0);
2120 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2121 into a register and then store it back out. */
2122 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2123 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2124 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2125 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2126 > GET_MODE_SIZE (GET_MODE (var))))
2128 replacement = find_fixup_replacement (replacements, var);
2129 if (replacement->new == 0)
2130 replacement->new = gen_reg_rtx (GET_MODE (var));
2132 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2133 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2136 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2137 insn into a pseudo and store the low part of the pseudo into VAR. */
2138 if (GET_CODE (SET_DEST (x)) == SUBREG
2139 && SUBREG_REG (SET_DEST (x)) == var
2140 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2141 > GET_MODE_SIZE (GET_MODE (var))))
2143 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2144 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2151 rtx dest = SET_DEST (x);
2152 rtx src = SET_SRC (x);
2153 rtx outerdest = dest;
2155 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2156 || GET_CODE (dest) == SIGN_EXTRACT
2157 || GET_CODE (dest) == ZERO_EXTRACT)
2158 dest = XEXP (dest, 0);
2160 if (GET_CODE (src) == SUBREG)
2161 src = SUBREG_REG (src);
2163 /* If VAR does not appear at the top level of the SET
2164 just scan the lower levels of the tree. */
2166 if (src != var && dest != var)
2169 /* We will need to rerecognize this insn. */
2170 INSN_CODE (insn) = -1;
2172 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var
2173 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE)
2175 /* Since this case will return, ensure we fixup all the
2177 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2178 insn, replacements, no_share);
2179 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2180 insn, replacements, no_share);
2181 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2182 insn, replacements, no_share);
2184 tem = XEXP (outerdest, 0);
2186 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2187 that may appear inside a ZERO_EXTRACT.
2188 This was legitimate when the MEM was a REG. */
2189 if (GET_CODE (tem) == SUBREG
2190 && SUBREG_REG (tem) == var)
2191 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2193 tem = fixup_stack_1 (tem, insn);
2195 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2196 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2197 && ! mode_dependent_address_p (XEXP (tem, 0))
2198 && ! MEM_VOLATILE_P (tem))
2200 enum machine_mode wanted_mode;
2201 enum machine_mode is_mode = GET_MODE (tem);
2202 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2204 wanted_mode = mode_for_extraction (EP_insv, 0);
2206 /* If we have a narrower mode, we can do something. */
2207 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2209 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2210 rtx old_pos = XEXP (outerdest, 2);
2213 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2214 offset = (GET_MODE_SIZE (is_mode)
2215 - GET_MODE_SIZE (wanted_mode) - offset);
2217 pos %= GET_MODE_BITSIZE (wanted_mode);
2219 newmem = adjust_address_nv (tem, wanted_mode, offset);
2221 /* Make the change and see if the insn remains valid. */
2222 INSN_CODE (insn) = -1;
2223 XEXP (outerdest, 0) = newmem;
2224 XEXP (outerdest, 2) = GEN_INT (pos);
2226 if (recog_memoized (insn) >= 0)
2229 /* Otherwise, restore old position. XEXP (x, 0) will be
2231 XEXP (outerdest, 2) = old_pos;
2235 /* If we get here, the bit-field store doesn't allow memory
2236 or isn't located at a constant position. Load the value into
2237 a register, do the store, and put it back into memory. */
2239 tem1 = gen_reg_rtx (GET_MODE (tem));
2240 emit_insn_before (gen_move_insn (tem1, tem), insn);
2241 emit_insn_after (gen_move_insn (tem, tem1), insn);
2242 XEXP (outerdest, 0) = tem1;
2246 /* STRICT_LOW_PART is a no-op on memory references
2247 and it can cause combinations to be unrecognizable,
2250 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2251 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2253 /* A valid insn to copy VAR into or out of a register
2254 must be left alone, to avoid an infinite loop here.
2255 If the reference to VAR is by a subreg, fix that up,
2256 since SUBREG is not valid for a memref.
2257 Also fix up the address of the stack slot.
2259 Note that we must not try to recognize the insn until
2260 after we know that we have valid addresses and no
2261 (subreg (mem ...) ...) constructs, since these interfere
2262 with determining the validity of the insn. */
2264 if ((SET_SRC (x) == var
2265 || (GET_CODE (SET_SRC (x)) == SUBREG
2266 && SUBREG_REG (SET_SRC (x)) == var))
2267 && (GET_CODE (SET_DEST (x)) == REG
2268 || (GET_CODE (SET_DEST (x)) == SUBREG
2269 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2270 && GET_MODE (var) == promoted_mode
2271 && x == single_set (insn))
2275 if (GET_CODE (SET_SRC (x)) == SUBREG
2276 && (GET_MODE_SIZE (GET_MODE (SET_SRC (x)))
2277 > GET_MODE_SIZE (GET_MODE (var))))
2279 /* This (subreg VAR) is now a paradoxical subreg. We need
2280 to replace VAR instead of the subreg. */
2281 replacement = find_fixup_replacement (replacements, var);
2282 if (replacement->new == NULL_RTX)
2283 replacement->new = gen_reg_rtx (GET_MODE (var));
2284 SUBREG_REG (SET_SRC (x)) = replacement->new;
2288 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2289 if (replacement->new)
2290 SET_SRC (x) = replacement->new;
2291 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2292 SET_SRC (x) = replacement->new
2293 = fixup_memory_subreg (SET_SRC (x), insn, promoted_mode,
2296 SET_SRC (x) = replacement->new
2297 = fixup_stack_1 (SET_SRC (x), insn);
2300 if (recog_memoized (insn) >= 0)
2303 /* INSN is not valid, but we know that we want to
2304 copy SET_SRC (x) to SET_DEST (x) in some way. So
2305 we generate the move and see whether it requires more
2306 than one insn. If it does, we emit those insns and
2307 delete INSN. Otherwise, we can just replace the pattern
2308 of INSN; we have already verified above that INSN has
2309 no other function that to do X. */
2311 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2312 if (NEXT_INSN (pat) != NULL_RTX)
2314 last = emit_insn_before (pat, insn);
2316 /* INSN might have REG_RETVAL or other important notes, so
2317 we need to store the pattern of the last insn in the
2318 sequence into INSN similarly to the normal case. LAST
2319 should not have REG_NOTES, but we allow them if INSN has
2321 if (REG_NOTES (last) && REG_NOTES (insn))
2323 if (REG_NOTES (last))
2324 REG_NOTES (insn) = REG_NOTES (last);
2325 PATTERN (insn) = PATTERN (last);
2330 PATTERN (insn) = PATTERN (pat);
2335 if ((SET_DEST (x) == var
2336 || (GET_CODE (SET_DEST (x)) == SUBREG
2337 && SUBREG_REG (SET_DEST (x)) == var))
2338 && (GET_CODE (SET_SRC (x)) == REG
2339 || (GET_CODE (SET_SRC (x)) == SUBREG
2340 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2341 && GET_MODE (var) == promoted_mode
2342 && x == single_set (insn))
2346 if (GET_CODE (SET_DEST (x)) == SUBREG)
2347 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn,
2350 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2352 if (recog_memoized (insn) >= 0)
2355 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2356 if (NEXT_INSN (pat) != NULL_RTX)
2358 last = emit_insn_before (pat, insn);
2360 /* INSN might have REG_RETVAL or other important notes, so
2361 we need to store the pattern of the last insn in the
2362 sequence into INSN similarly to the normal case. LAST
2363 should not have REG_NOTES, but we allow them if INSN has
2365 if (REG_NOTES (last) && REG_NOTES (insn))
2367 if (REG_NOTES (last))
2368 REG_NOTES (insn) = REG_NOTES (last);
2369 PATTERN (insn) = PATTERN (last);
2374 PATTERN (insn) = PATTERN (pat);
2379 /* Otherwise, storing into VAR must be handled specially
2380 by storing into a temporary and copying that into VAR
2381 with a new insn after this one. Note that this case
2382 will be used when storing into a promoted scalar since
2383 the insn will now have different modes on the input
2384 and output and hence will be invalid (except for the case
2385 of setting it to a constant, which does not need any
2386 change if it is valid). We generate extra code in that case,
2387 but combine.c will eliminate it. */
2392 rtx fixeddest = SET_DEST (x);
2393 enum machine_mode temp_mode;
2395 /* STRICT_LOW_PART can be discarded, around a MEM. */
2396 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2397 fixeddest = XEXP (fixeddest, 0);
2398 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2399 if (GET_CODE (fixeddest) == SUBREG)
2401 fixeddest = fixup_memory_subreg (fixeddest, insn,
2403 temp_mode = GET_MODE (fixeddest);
2407 fixeddest = fixup_stack_1 (fixeddest, insn);
2408 temp_mode = promoted_mode;
2411 temp = gen_reg_rtx (temp_mode);
2413 emit_insn_after (gen_move_insn (fixeddest,
2414 gen_lowpart (GET_MODE (fixeddest),
2418 SET_DEST (x) = temp;
2426 /* Nothing special about this RTX; fix its operands. */
2428 fmt = GET_RTX_FORMAT (code);
2429 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2432 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements,
2434 else if (fmt[i] == 'E')
2437 for (j = 0; j < XVECLEN (x, i); j++)
2438 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2439 insn, replacements, no_share);
2444 /* Previously, X had the form (SUBREG:m1 (REG:PROMOTED_MODE ...)).
2445 The REG was placed on the stack, so X now has the form (SUBREG:m1
2448 Return an rtx (MEM:m1 newaddr) which is equivalent. If any insns
2449 must be emitted to compute NEWADDR, put them before INSN.
2451 UNCRITICAL nonzero means accept paradoxical subregs.
2452 This is used for subregs found inside REG_NOTES. */
2455 fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode, int uncritical)
2458 rtx mem = SUBREG_REG (x);
2459 rtx addr = XEXP (mem, 0);
2460 enum machine_mode mode = GET_MODE (x);
2463 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2464 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (mem)) && ! uncritical)
2467 offset = SUBREG_BYTE (x);
2468 if (BYTES_BIG_ENDIAN)
2469 /* If the PROMOTED_MODE is wider than the mode of the MEM, adjust
2470 the offset so that it points to the right location within the
2472 offset -= (GET_MODE_SIZE (promoted_mode) - GET_MODE_SIZE (GET_MODE (mem)));
2474 if (!flag_force_addr
2475 && memory_address_p (mode, plus_constant (addr, offset)))
2476 /* Shortcut if no insns need be emitted. */
2477 return adjust_address (mem, mode, offset);
2480 result = adjust_address (mem, mode, offset);
2484 emit_insn_before (seq, insn);
2488 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2489 Replace subexpressions of X in place.
2490 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2491 Otherwise return X, with its contents possibly altered.
2493 INSN, PROMOTED_MODE and UNCRITICAL are as for
2494 fixup_memory_subreg. */
2497 walk_fixup_memory_subreg (rtx x, rtx insn, enum machine_mode promoted_mode,
2507 code = GET_CODE (x);
2509 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2510 return fixup_memory_subreg (x, insn, promoted_mode, uncritical);
2512 /* Nothing special about this RTX; fix its operands. */
2514 fmt = GET_RTX_FORMAT (code);
2515 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2518 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn,
2519 promoted_mode, uncritical);
2520 else if (fmt[i] == 'E')
2523 for (j = 0; j < XVECLEN (x, i); j++)
2525 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn,
2526 promoted_mode, uncritical);
2532 /* For each memory ref within X, if it refers to a stack slot
2533 with an out of range displacement, put the address in a temp register
2534 (emitting new insns before INSN to load these registers)
2535 and alter the memory ref to use that register.
2536 Replace each such MEM rtx with a copy, to avoid clobberage. */
2539 fixup_stack_1 (rtx x, rtx insn)
2542 RTX_CODE code = GET_CODE (x);
2547 rtx ad = XEXP (x, 0);
2548 /* If we have address of a stack slot but it's not valid
2549 (displacement is too large), compute the sum in a register. */
2550 if (GET_CODE (ad) == PLUS
2551 && GET_CODE (XEXP (ad, 0)) == REG
2552 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2553 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2554 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2555 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2556 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2558 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2559 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2560 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2561 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2564 if (memory_address_p (GET_MODE (x), ad))
2568 temp = copy_to_reg (ad);
2571 emit_insn_before (seq, insn);
2572 return replace_equiv_address (x, temp);
2577 fmt = GET_RTX_FORMAT (code);
2578 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2581 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2582 else if (fmt[i] == 'E')
2585 for (j = 0; j < XVECLEN (x, i); j++)
2586 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2592 /* Optimization: a bit-field instruction whose field
2593 happens to be a byte or halfword in memory
2594 can be changed to a move instruction.
2596 We call here when INSN is an insn to examine or store into a bit-field.
2597 BODY is the SET-rtx to be altered.
2599 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2600 (Currently this is called only from function.c, and EQUIV_MEM
2604 optimize_bit_field (rtx body, rtx insn, rtx *equiv_mem)
2609 enum machine_mode mode;
2611 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2612 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2613 bitfield = SET_DEST (body), destflag = 1;
2615 bitfield = SET_SRC (body), destflag = 0;
2617 /* First check that the field being stored has constant size and position
2618 and is in fact a byte or halfword suitably aligned. */
2620 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2621 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2622 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2624 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2628 /* Now check that the containing word is memory, not a register,
2629 and that it is safe to change the machine mode. */
2631 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2632 memref = XEXP (bitfield, 0);
2633 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2635 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2636 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2637 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2638 memref = SUBREG_REG (XEXP (bitfield, 0));
2639 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2641 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2642 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2645 && ! mode_dependent_address_p (XEXP (memref, 0))
2646 && ! MEM_VOLATILE_P (memref))
2648 /* Now adjust the address, first for any subreg'ing
2649 that we are now getting rid of,
2650 and then for which byte of the word is wanted. */
2652 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2655 /* Adjust OFFSET to count bits from low-address byte. */
2656 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2657 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2658 - offset - INTVAL (XEXP (bitfield, 1)));
2660 /* Adjust OFFSET to count bytes from low-address byte. */
2661 offset /= BITS_PER_UNIT;
2662 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2664 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2665 / UNITS_PER_WORD) * UNITS_PER_WORD;
2666 if (BYTES_BIG_ENDIAN)
2667 offset -= (MIN (UNITS_PER_WORD,
2668 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2669 - MIN (UNITS_PER_WORD,
2670 GET_MODE_SIZE (GET_MODE (memref))));
2674 memref = adjust_address (memref, mode, offset);
2675 insns = get_insns ();
2677 emit_insn_before (insns, insn);
2679 /* Store this memory reference where
2680 we found the bit field reference. */
2684 validate_change (insn, &SET_DEST (body), memref, 1);
2685 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2687 rtx src = SET_SRC (body);
2688 while (GET_CODE (src) == SUBREG
2689 && SUBREG_BYTE (src) == 0)
2690 src = SUBREG_REG (src);
2691 if (GET_MODE (src) != GET_MODE (memref))
2692 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2693 validate_change (insn, &SET_SRC (body), src, 1);
2695 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2696 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2697 /* This shouldn't happen because anything that didn't have
2698 one of these modes should have got converted explicitly
2699 and then referenced through a subreg.
2700 This is so because the original bit-field was
2701 handled by agg_mode and so its tree structure had
2702 the same mode that memref now has. */
2707 rtx dest = SET_DEST (body);
2709 while (GET_CODE (dest) == SUBREG
2710 && SUBREG_BYTE (dest) == 0
2711 && (GET_MODE_CLASS (GET_MODE (dest))
2712 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2713 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2715 dest = SUBREG_REG (dest);
2717 validate_change (insn, &SET_DEST (body), dest, 1);
2719 if (GET_MODE (dest) == GET_MODE (memref))
2720 validate_change (insn, &SET_SRC (body), memref, 1);
2723 /* Convert the mem ref to the destination mode. */
2724 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2727 convert_move (newreg, memref,
2728 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2732 validate_change (insn, &SET_SRC (body), newreg, 1);
2736 /* See if we can convert this extraction or insertion into
2737 a simple move insn. We might not be able to do so if this
2738 was, for example, part of a PARALLEL.
2740 If we succeed, write out any needed conversions. If we fail,
2741 it is hard to guess why we failed, so don't do anything
2742 special; just let the optimization be suppressed. */
2744 if (apply_change_group () && seq)
2745 emit_insn_before (seq, insn);
2750 /* These routines are responsible for converting virtual register references
2751 to the actual hard register references once RTL generation is complete.
2753 The following four variables are used for communication between the
2754 routines. They contain the offsets of the virtual registers from their
2755 respective hard registers. */
2757 static int in_arg_offset;
2758 static int var_offset;
2759 static int dynamic_offset;
2760 static int out_arg_offset;
2761 static int cfa_offset;
2763 /* In most machines, the stack pointer register is equivalent to the bottom
2766 #ifndef STACK_POINTER_OFFSET
2767 #define STACK_POINTER_OFFSET 0
2770 /* If not defined, pick an appropriate default for the offset of dynamically
2771 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2772 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2774 #ifndef STACK_DYNAMIC_OFFSET
2776 /* The bottom of the stack points to the actual arguments. If
2777 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2778 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2779 stack space for register parameters is not pushed by the caller, but
2780 rather part of the fixed stack areas and hence not included in
2781 `current_function_outgoing_args_size'. Nevertheless, we must allow
2782 for it when allocating stack dynamic objects. */
2784 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2785 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2786 ((ACCUMULATE_OUTGOING_ARGS \
2787 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2788 + (STACK_POINTER_OFFSET)) \
2791 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2792 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2793 + (STACK_POINTER_OFFSET))
2797 /* On most machines, the CFA coincides with the first incoming parm. */
2799 #ifndef ARG_POINTER_CFA_OFFSET
2800 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2803 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just
2804 had its address taken. DECL is the decl or SAVE_EXPR for the
2805 object stored in the register, for later use if we do need to force
2806 REG into the stack. REG is overwritten by the MEM like in
2807 put_reg_into_stack. RESCAN is true if previously emitted
2808 instructions must be rescanned and modified now that the REG has
2809 been transformed. */
2812 gen_mem_addressof (rtx reg, tree decl, int rescan)
2814 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2817 /* Calculate this before we start messing with decl's RTL. */
2818 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0;
2820 /* If the original REG was a user-variable, then so is the REG whose
2821 address is being taken. Likewise for unchanging. */
2822 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2823 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2825 PUT_CODE (reg, MEM);
2826 MEM_ATTRS (reg) = 0;
2831 tree type = TREE_TYPE (decl);
2832 enum machine_mode decl_mode
2833 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl)));
2834 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl)
2835 : DECL_RTL_IF_SET (decl));
2837 PUT_MODE (reg, decl_mode);
2839 /* Clear DECL_RTL momentarily so functions below will work
2840 properly, then set it again. */
2841 if (DECL_P (decl) && decl_rtl == reg)
2842 SET_DECL_RTL (decl, 0);
2844 set_mem_attributes (reg, decl, 1);
2845 set_mem_alias_set (reg, set);
2847 if (DECL_P (decl) && decl_rtl == reg)
2848 SET_DECL_RTL (decl, reg);
2851 && (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0)))
2852 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), reg, 0);
2855 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0);
2860 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2863 flush_addressof (tree decl)
2865 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2866 && DECL_RTL (decl) != 0
2867 && GET_CODE (DECL_RTL (decl)) == MEM
2868 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2869 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2870 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2873 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2876 put_addressof_into_stack (rtx r, htab_t ht)
2879 int volatile_p, used_p;
2881 rtx reg = XEXP (r, 0);
2883 if (GET_CODE (reg) != REG)
2886 decl = ADDRESSOF_DECL (r);
2889 type = TREE_TYPE (decl);
2890 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2891 && TREE_THIS_VOLATILE (decl));
2892 used_p = (TREE_USED (decl)
2893 || (DECL_P (decl) && DECL_INITIAL (decl) != 0));
2902 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2903 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2906 /* List of replacements made below in purge_addressof_1 when creating
2907 bitfield insertions. */
2908 static rtx purge_bitfield_addressof_replacements;
2910 /* List of replacements made below in purge_addressof_1 for patterns
2911 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2912 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2913 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2914 enough in complex cases, e.g. when some field values can be
2915 extracted by usage MEM with narrower mode. */
2916 static rtx purge_addressof_replacements;
2918 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2919 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2920 the stack. If the function returns FALSE then the replacement could not
2921 be made. If MAY_POSTPONE is true and we would not put the addressof
2922 to stack, postpone processing of the insn. */
2925 purge_addressof_1 (rtx *loc, rtx insn, int force, int store, int may_postpone,
2933 bool libcall = false;
2935 /* Re-start here to avoid recursion in common cases. */
2942 /* Is this a libcall? */
2944 libcall = REG_NOTE_KIND (*loc) == REG_RETVAL;
2946 code = GET_CODE (x);
2948 /* If we don't return in any of the cases below, we will recurse inside
2949 the RTX, which will normally result in any ADDRESSOF being forced into
2953 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1,
2955 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0,
2959 else if (code == ADDRESSOF)
2963 if (GET_CODE (XEXP (x, 0)) != MEM)
2964 put_addressof_into_stack (x, ht);
2966 /* We must create a copy of the rtx because it was created by
2967 overwriting a REG rtx which is always shared. */
2968 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
2969 if (validate_change (insn, loc, sub, 0)
2970 || validate_replace_rtx (x, sub, insn))
2975 /* If SUB is a hard or virtual register, try it as a pseudo-register.
2976 Otherwise, perhaps SUB is an expression, so generate code to compute
2978 if (GET_CODE (sub) == REG && REGNO (sub) <= LAST_VIRTUAL_REGISTER)
2979 sub = copy_to_reg (sub);
2981 sub = force_operand (sub, NULL_RTX);
2983 if (! validate_change (insn, loc, sub, 0)
2984 && ! validate_replace_rtx (x, sub, insn))
2987 insns = get_insns ();
2989 emit_insn_before (insns, insn);
2993 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
2995 rtx sub = XEXP (XEXP (x, 0), 0);
2997 if (GET_CODE (sub) == MEM)
2998 sub = adjust_address_nv (sub, GET_MODE (x), 0);
2999 else if (GET_CODE (sub) == REG
3000 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3002 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3004 int size_x, size_sub;
3008 /* Postpone for now, so that we do not emit bitfield arithmetics
3009 unless there is some benefit from it. */
3010 if (!postponed_insns || XEXP (postponed_insns, 0) != insn)
3011 postponed_insns = alloc_INSN_LIST (insn, postponed_insns);
3017 /* When processing REG_NOTES look at the list of
3018 replacements done on the insn to find the register that X
3022 for (tem = purge_bitfield_addressof_replacements;
3024 tem = XEXP (XEXP (tem, 1), 1))
3025 if (rtx_equal_p (x, XEXP (tem, 0)))
3027 *loc = XEXP (XEXP (tem, 1), 0);
3031 /* See comment for purge_addressof_replacements. */
3032 for (tem = purge_addressof_replacements;
3034 tem = XEXP (XEXP (tem, 1), 1))
3035 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3037 rtx z = XEXP (XEXP (tem, 1), 0);
3039 if (GET_MODE (x) == GET_MODE (z)
3040 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3041 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3044 /* It can happen that the note may speak of things
3045 in a wider (or just different) mode than the
3046 code did. This is especially true of
3049 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3052 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3053 && (GET_MODE_SIZE (GET_MODE (x))
3054 > GET_MODE_SIZE (GET_MODE (z))))
3056 /* This can occur as a result in invalid
3057 pointer casts, e.g. float f; ...
3058 *(long long int *)&f.
3059 ??? We could emit a warning here, but
3060 without a line number that wouldn't be
3062 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3065 z = gen_lowpart (GET_MODE (x), z);
3071 /* When we are processing the REG_NOTES of the last instruction
3072 of a libcall, there will be typically no replacements
3073 for that insn; the replacements happened before, piecemeal
3074 fashion. OTOH we are not interested in the details of
3075 this for the REG_EQUAL note, we want to know the big picture,
3076 which can be succinctly described with a simple SUBREG.
3077 Note that removing the REG_EQUAL note is not an option
3078 on the last insn of a libcall, so we must do a replacement. */
3080 /* In compile/990107-1.c:7 compiled at -O1 -m1 for sh-elf,
3082 (mem:DI (addressof:SI (reg/v:DF 160) 159 0x401c8510)
3083 [0 S8 A32]), which can be expressed with a simple
3085 if ((GET_MODE_SIZE (GET_MODE (x))
3086 <= GET_MODE_SIZE (GET_MODE (sub)))
3087 /* Again, invalid pointer casts (as in
3088 compile/990203-1.c) can require paradoxical
3090 || (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3091 && (GET_MODE_SIZE (GET_MODE (x))
3092 > GET_MODE_SIZE (GET_MODE (sub)))
3095 *loc = gen_rtx_SUBREG (GET_MODE (x), sub, 0);
3098 /* ??? Are there other cases we should handle? */
3100 /* Sometimes we may not be able to find the replacement. For
3101 example when the original insn was a MEM in a wider mode,
3102 and the note is part of a sign extension of a narrowed
3103 version of that MEM. Gcc testcase compile/990829-1.c can
3104 generate an example of this situation. Rather than complain
3105 we return false, which will prompt our caller to remove the
3110 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3111 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3113 /* Do not frob unchanging MEMs. If a later reference forces the
3114 pseudo to the stack, we can wind up with multiple writes to
3115 an unchanging memory, which is invalid. */
3116 if (RTX_UNCHANGING_P (x) && size_x != size_sub)
3119 /* Don't even consider working with paradoxical subregs,
3120 or the moral equivalent seen here. */
3121 else if (size_x <= size_sub
3122 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3124 /* Do a bitfield insertion to mirror what would happen
3131 rtx p = PREV_INSN (insn);
3134 val = gen_reg_rtx (GET_MODE (x));
3135 if (! validate_change (insn, loc, val, 0))
3137 /* Discard the current sequence and put the
3138 ADDRESSOF on stack. */
3144 emit_insn_before (seq, insn);
3145 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3149 store_bit_field (sub, size_x, 0, GET_MODE (x),
3150 val, GET_MODE_SIZE (GET_MODE (sub)));
3152 /* Make sure to unshare any shared rtl that store_bit_field
3153 might have created. */
3154 unshare_all_rtl_again (get_insns ());
3158 p = emit_insn_after (seq, insn);
3159 if (NEXT_INSN (insn))
3160 compute_insns_for_mem (NEXT_INSN (insn),
3161 p ? NEXT_INSN (p) : NULL_RTX,
3166 rtx p = PREV_INSN (insn);
3169 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3170 GET_MODE (x), GET_MODE (x),
3171 GET_MODE_SIZE (GET_MODE (sub)));
3173 if (! validate_change (insn, loc, val, 0))
3175 /* Discard the current sequence and put the
3176 ADDRESSOF on stack. */
3183 emit_insn_before (seq, insn);
3184 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3188 /* Remember the replacement so that the same one can be done
3189 on the REG_NOTES. */
3190 purge_bitfield_addressof_replacements
3191 = gen_rtx_EXPR_LIST (VOIDmode, x,
3194 purge_bitfield_addressof_replacements));
3196 /* We replaced with a reg -- all done. */
3201 else if (validate_change (insn, loc, sub, 0))
3203 /* Remember the replacement so that the same one can be done
3204 on the REG_NOTES. */
3205 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3209 for (tem = purge_addressof_replacements;
3211 tem = XEXP (XEXP (tem, 1), 1))
3212 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3214 XEXP (XEXP (tem, 1), 0) = sub;
3217 purge_addressof_replacements
3218 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3219 gen_rtx_EXPR_LIST (VOIDmode, sub,
3220 purge_addressof_replacements));
3228 /* Scan all subexpressions. */
3229 fmt = GET_RTX_FORMAT (code);
3230 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3233 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0,
3235 else if (*fmt == 'E')
3236 for (j = 0; j < XVECLEN (x, i); j++)
3237 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0,
3244 /* Return a hash value for K, a REG. */
3247 insns_for_mem_hash (const void *k)
3249 /* Use the address of the key for the hash value. */
3250 struct insns_for_mem_entry *m = (struct insns_for_mem_entry *) k;
3251 return htab_hash_pointer (m->key);
3254 /* Return nonzero if K1 and K2 (two REGs) are the same. */
3257 insns_for_mem_comp (const void *k1, const void *k2)
3259 struct insns_for_mem_entry *m1 = (struct insns_for_mem_entry *) k1;
3260 struct insns_for_mem_entry *m2 = (struct insns_for_mem_entry *) k2;
3261 return m1->key == m2->key;
3264 struct insns_for_mem_walk_info
3266 /* The hash table that we are using to record which INSNs use which
3270 /* The INSN we are currently processing. */
3273 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3274 to find the insns that use the REGs in the ADDRESSOFs. */
3278 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3279 that might be used in an ADDRESSOF expression, record this INSN in
3280 the hash table given by DATA (which is really a pointer to an
3281 insns_for_mem_walk_info structure). */
3284 insns_for_mem_walk (rtx *r, void *data)
3286 struct insns_for_mem_walk_info *ifmwi
3287 = (struct insns_for_mem_walk_info *) data;
3288 struct insns_for_mem_entry tmp;
3289 tmp.insns = NULL_RTX;
3291 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3292 && GET_CODE (XEXP (*r, 0)) == REG)
3295 tmp.key = XEXP (*r, 0);
3296 e = htab_find_slot (ifmwi->ht, &tmp, INSERT);
3299 *e = ggc_alloc (sizeof (tmp));
3300 memcpy (*e, &tmp, sizeof (tmp));
3303 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3305 struct insns_for_mem_entry *ifme;
3307 ifme = htab_find (ifmwi->ht, &tmp);
3309 /* If we have not already recorded this INSN, do so now. Since
3310 we process the INSNs in order, we know that if we have
3311 recorded it it must be at the front of the list. */
3312 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3313 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3320 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3321 which REGs in HT. */
3324 compute_insns_for_mem (rtx insns, rtx last_insn, htab_t ht)
3327 struct insns_for_mem_walk_info ifmwi;
3330 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3331 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3335 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3339 /* Helper function for purge_addressof called through for_each_rtx.
3340 Returns true iff the rtl is an ADDRESSOF. */
3343 is_addressof (rtx *rtl, void *data ATTRIBUTE_UNUSED)
3345 return GET_CODE (*rtl) == ADDRESSOF;
3348 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3349 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3353 purge_addressof (rtx insns)
3358 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3359 requires a fixup pass over the instruction stream to correct
3360 INSNs that depended on the REG being a REG, and not a MEM. But,
3361 these fixup passes are slow. Furthermore, most MEMs are not
3362 mentioned in very many instructions. So, we speed up the process
3363 by pre-calculating which REGs occur in which INSNs; that allows
3364 us to perform the fixup passes much more quickly. */
3365 ht = htab_create_ggc (1000, insns_for_mem_hash, insns_for_mem_comp, NULL);
3366 compute_insns_for_mem (insns, NULL_RTX, ht);
3368 postponed_insns = NULL;
3370 for (insn = insns; insn; insn = NEXT_INSN (insn))
3373 if (! purge_addressof_1 (&PATTERN (insn), insn,
3374 asm_noperands (PATTERN (insn)) > 0, 0, 1, ht))
3375 /* If we could not replace the ADDRESSOFs in the insn,
3376 something is wrong. */
3379 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, 0, ht))
3381 /* If we could not replace the ADDRESSOFs in the insn's notes,
3382 we can just remove the offending notes instead. */
3385 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3387 /* If we find a REG_RETVAL note then the insn is a libcall.
3388 Such insns must have REG_EQUAL notes as well, in order
3389 for later passes of the compiler to work. So it is not
3390 safe to delete the notes here, and instead we abort. */
3391 if (REG_NOTE_KIND (note) == REG_RETVAL)
3393 if (for_each_rtx (¬e, is_addressof, NULL))
3394 remove_note (insn, note);
3399 /* Process the postponed insns. */
3400 while (postponed_insns)
3402 insn = XEXP (postponed_insns, 0);
3403 tmp = postponed_insns;
3404 postponed_insns = XEXP (postponed_insns, 1);
3405 free_INSN_LIST_node (tmp);
3407 if (! purge_addressof_1 (&PATTERN (insn), insn,
3408 asm_noperands (PATTERN (insn)) > 0, 0, 0, ht))
3413 purge_bitfield_addressof_replacements = 0;
3414 purge_addressof_replacements = 0;
3416 /* REGs are shared. purge_addressof will destructively replace a REG
3417 with a MEM, which creates shared MEMs.
3419 Unfortunately, the children of put_reg_into_stack assume that MEMs
3420 referring to the same stack slot are shared (fixup_var_refs and
3421 the associated hash table code).
3423 So, we have to do another unsharing pass after we have flushed any
3424 REGs that had their address taken into the stack.
3426 It may be worth tracking whether or not we converted any REGs into
3427 MEMs to avoid this overhead when it is not needed. */
3428 unshare_all_rtl_again (get_insns ());
3431 /* Convert a SET of a hard subreg to a set of the appropriate hard
3432 register. A subroutine of purge_hard_subreg_sets. */
3435 purge_single_hard_subreg_set (rtx pattern)
3437 rtx reg = SET_DEST (pattern);
3438 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3441 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3442 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3444 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3445 GET_MODE (SUBREG_REG (reg)),
3448 reg = SUBREG_REG (reg);
3452 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3454 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3455 SET_DEST (pattern) = reg;
3459 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3460 only such SETs that we expect to see are those left in because
3461 integrate can't handle sets of parts of a return value register.
3463 We don't use alter_subreg because we only want to eliminate subregs
3464 of hard registers. */
3467 purge_hard_subreg_sets (rtx insn)
3469 for (; insn; insn = NEXT_INSN (insn))
3473 rtx pattern = PATTERN (insn);
3474 switch (GET_CODE (pattern))
3477 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3478 purge_single_hard_subreg_set (pattern);
3483 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3485 rtx inner_pattern = XVECEXP (pattern, 0, j);
3486 if (GET_CODE (inner_pattern) == SET
3487 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3488 purge_single_hard_subreg_set (inner_pattern);
3499 /* Pass through the INSNS of function FNDECL and convert virtual register
3500 references to hard register references. */
3503 instantiate_virtual_regs (tree fndecl, rtx insns)
3508 /* Compute the offsets to use for this function. */
3509 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3510 var_offset = STARTING_FRAME_OFFSET;
3511 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3512 out_arg_offset = STACK_POINTER_OFFSET;
3513 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3515 /* Scan all variables and parameters of this function. For each that is
3516 in memory, instantiate all virtual registers if the result is a valid
3517 address. If not, we do it later. That will handle most uses of virtual
3518 regs on many machines. */
3519 instantiate_decls (fndecl, 1);
3521 /* Initialize recognition, indicating that volatile is OK. */
3524 /* Scan through all the insns, instantiating every virtual register still
3526 for (insn = insns; insn; insn = NEXT_INSN (insn))
3527 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3528 || GET_CODE (insn) == CALL_INSN)
3530 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3531 if (INSN_DELETED_P (insn))
3533 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3534 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3535 if (GET_CODE (insn) == CALL_INSN)
3536 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3539 /* Past this point all ASM statements should match. Verify that
3540 to avoid failures later in the compilation process. */
3541 if (asm_noperands (PATTERN (insn)) >= 0
3542 && ! check_asm_operands (PATTERN (insn)))
3543 instantiate_virtual_regs_lossage (insn);
3546 /* Instantiate the stack slots for the parm registers, for later use in
3547 addressof elimination. */
3548 for (i = 0; i < max_parm_reg; ++i)
3549 if (parm_reg_stack_loc[i])
3550 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3552 /* Now instantiate the remaining register equivalences for debugging info.
3553 These will not be valid addresses. */
3554 instantiate_decls (fndecl, 0);
3556 /* Indicate that, from now on, assign_stack_local should use
3557 frame_pointer_rtx. */
3558 virtuals_instantiated = 1;
3561 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3562 all virtual registers in their DECL_RTL's.
3564 If VALID_ONLY, do this only if the resulting address is still valid.
3565 Otherwise, always do it. */
3568 instantiate_decls (tree fndecl, int valid_only)
3572 /* Process all parameters of the function. */
3573 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3575 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3576 HOST_WIDE_INT size_rtl;
3578 instantiate_decl (DECL_RTL (decl), size, valid_only);
3580 /* If the parameter was promoted, then the incoming RTL mode may be
3581 larger than the declared type size. We must use the larger of
3583 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3584 size = MAX (size_rtl, size);
3585 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3588 /* Now process all variables defined in the function or its subblocks. */
3589 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3592 /* Subroutine of instantiate_decls: Process all decls in the given
3593 BLOCK node and all its subblocks. */
3596 instantiate_decls_1 (tree let, int valid_only)
3600 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3601 if (DECL_RTL_SET_P (t))
3602 instantiate_decl (DECL_RTL (t),
3603 int_size_in_bytes (TREE_TYPE (t)),
3606 /* Process all subblocks. */
3607 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3608 instantiate_decls_1 (t, valid_only);
3611 /* Subroutine of the preceding procedures: Given RTL representing a
3612 decl and the size of the object, do any instantiation required.
3614 If VALID_ONLY is nonzero, it means that the RTL should only be
3615 changed if the new address is valid. */
3618 instantiate_decl (rtx x, HOST_WIDE_INT size, int valid_only)
3620 enum machine_mode mode;
3623 /* If this is not a MEM, no need to do anything. Similarly if the
3624 address is a constant or a register that is not a virtual register. */
3626 if (x == 0 || GET_CODE (x) != MEM)
3630 if (CONSTANT_P (addr)
3631 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3632 || (GET_CODE (addr) == REG
3633 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3634 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3637 /* If we should only do this if the address is valid, copy the address.
3638 We need to do this so we can undo any changes that might make the
3639 address invalid. This copy is unfortunate, but probably can't be
3643 addr = copy_rtx (addr);
3645 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3647 if (valid_only && size >= 0)
3649 unsigned HOST_WIDE_INT decl_size = size;
3651 /* Now verify that the resulting address is valid for every integer or
3652 floating-point mode up to and including SIZE bytes long. We do this
3653 since the object might be accessed in any mode and frame addresses
3656 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3657 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3658 mode = GET_MODE_WIDER_MODE (mode))
3659 if (! memory_address_p (mode, addr))
3662 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3663 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3664 mode = GET_MODE_WIDER_MODE (mode))
3665 if (! memory_address_p (mode, addr))
3669 /* Put back the address now that we have updated it and we either know
3670 it is valid or we don't care whether it is valid. */
3675 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3676 is a virtual register, return the equivalent hard register and set the
3677 offset indirectly through the pointer. Otherwise, return 0. */
3680 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
3683 HOST_WIDE_INT offset;
3685 if (x == virtual_incoming_args_rtx)
3686 new = arg_pointer_rtx, offset = in_arg_offset;
3687 else if (x == virtual_stack_vars_rtx)
3688 new = frame_pointer_rtx, offset = var_offset;
3689 else if (x == virtual_stack_dynamic_rtx)
3690 new = stack_pointer_rtx, offset = dynamic_offset;
3691 else if (x == virtual_outgoing_args_rtx)
3692 new = stack_pointer_rtx, offset = out_arg_offset;
3693 else if (x == virtual_cfa_rtx)
3694 new = arg_pointer_rtx, offset = cfa_offset;
3703 /* Called when instantiate_virtual_regs has failed to update the instruction.
3704 Usually this means that non-matching instruction has been emit, however for
3705 asm statements it may be the problem in the constraints. */
3707 instantiate_virtual_regs_lossage (rtx insn)
3709 if (asm_noperands (PATTERN (insn)) >= 0)
3711 error_for_asm (insn, "impossible constraint in `asm'");
3717 /* Given a pointer to a piece of rtx and an optional pointer to the
3718 containing object, instantiate any virtual registers present in it.
3720 If EXTRA_INSNS, we always do the replacement and generate
3721 any extra insns before OBJECT. If it zero, we do nothing if replacement
3724 Return 1 if we either had nothing to do or if we were able to do the
3725 needed replacement. Return 0 otherwise; we only return zero if
3726 EXTRA_INSNS is zero.
3728 We first try some simple transformations to avoid the creation of extra
3732 instantiate_virtual_regs_1 (rtx *loc, rtx object, int extra_insns)
3737 HOST_WIDE_INT offset = 0;
3743 /* Re-start here to avoid recursion in common cases. */
3750 /* We may have detected and deleted invalid asm statements. */
3751 if (object && INSN_P (object) && INSN_DELETED_P (object))
3754 code = GET_CODE (x);
3756 /* Check for some special cases. */
3774 /* We are allowed to set the virtual registers. This means that
3775 the actual register should receive the source minus the
3776 appropriate offset. This is used, for example, in the handling
3777 of non-local gotos. */
3778 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3780 rtx src = SET_SRC (x);
3782 /* We are setting the register, not using it, so the relevant
3783 offset is the negative of the offset to use were we using
3786 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3788 /* The only valid sources here are PLUS or REG. Just do
3789 the simplest possible thing to handle them. */
3790 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3792 instantiate_virtual_regs_lossage (object);
3797 if (GET_CODE (src) != REG)
3798 temp = force_operand (src, NULL_RTX);
3801 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3805 emit_insn_before (seq, object);
3808 if (! validate_change (object, &SET_SRC (x), temp, 0)
3810 instantiate_virtual_regs_lossage (object);
3815 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3820 /* Handle special case of virtual register plus constant. */
3821 if (CONSTANT_P (XEXP (x, 1)))
3823 rtx old, new_offset;
3825 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3826 if (GET_CODE (XEXP (x, 0)) == PLUS)
3828 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3830 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3832 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3841 #ifdef POINTERS_EXTEND_UNSIGNED
3842 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3843 we can commute the PLUS and SUBREG because pointers into the
3844 frame are well-behaved. */
3845 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3846 && GET_CODE (XEXP (x, 1)) == CONST_INT
3848 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3850 && validate_change (object, loc,
3851 plus_constant (gen_lowpart (ptr_mode,
3854 + INTVAL (XEXP (x, 1))),
3858 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3860 /* We know the second operand is a constant. Unless the
3861 first operand is a REG (which has been already checked),
3862 it needs to be checked. */
3863 if (GET_CODE (XEXP (x, 0)) != REG)
3871 new_offset = plus_constant (XEXP (x, 1), offset);
3873 /* If the new constant is zero, try to replace the sum with just
3875 if (new_offset == const0_rtx
3876 && validate_change (object, loc, new, 0))
3879 /* Next try to replace the register and new offset.
3880 There are two changes to validate here and we can't assume that
3881 in the case of old offset equals new just changing the register
3882 will yield a valid insn. In the interests of a little efficiency,
3883 however, we only call validate change once (we don't queue up the
3884 changes and then call apply_change_group). */
3888 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3889 : (XEXP (x, 0) = new,
3890 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3898 /* Otherwise copy the new constant into a register and replace
3899 constant with that register. */
3900 temp = gen_reg_rtx (Pmode);
3902 if (validate_change (object, &XEXP (x, 1), temp, 0))
3903 emit_insn_before (gen_move_insn (temp, new_offset), object);
3906 /* If that didn't work, replace this expression with a
3907 register containing the sum. */
3910 new = gen_rtx_PLUS (Pmode, new, new_offset);
3913 temp = force_operand (new, NULL_RTX);
3917 emit_insn_before (seq, object);
3918 if (! validate_change (object, loc, temp, 0)
3919 && ! validate_replace_rtx (x, temp, object))
3921 instantiate_virtual_regs_lossage (object);
3930 /* Fall through to generic two-operand expression case. */
3936 case DIV: case UDIV:
3937 case MOD: case UMOD:
3938 case AND: case IOR: case XOR:
3939 case ROTATERT: case ROTATE:
3940 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3942 case GE: case GT: case GEU: case GTU:
3943 case LE: case LT: case LEU: case LTU:
3944 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3945 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3950 /* Most cases of MEM that convert to valid addresses have already been
3951 handled by our scan of decls. The only special handling we
3952 need here is to make a copy of the rtx to ensure it isn't being
3953 shared if we have to change it to a pseudo.
3955 If the rtx is a simple reference to an address via a virtual register,
3956 it can potentially be shared. In such cases, first try to make it
3957 a valid address, which can also be shared. Otherwise, copy it and
3960 First check for common cases that need no processing. These are
3961 usually due to instantiation already being done on a previous instance
3965 if (CONSTANT_ADDRESS_P (temp)
3966 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3967 || temp == arg_pointer_rtx
3969 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3970 || temp == hard_frame_pointer_rtx
3972 || temp == frame_pointer_rtx)
3975 if (GET_CODE (temp) == PLUS
3976 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3977 && (XEXP (temp, 0) == frame_pointer_rtx
3978 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3979 || XEXP (temp, 0) == hard_frame_pointer_rtx
3981 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3982 || XEXP (temp, 0) == arg_pointer_rtx
3987 if (temp == virtual_stack_vars_rtx
3988 || temp == virtual_incoming_args_rtx
3989 || (GET_CODE (temp) == PLUS
3990 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3991 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3992 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3994 /* This MEM may be shared. If the substitution can be done without
3995 the need to generate new pseudos, we want to do it in place
3996 so all copies of the shared rtx benefit. The call below will
3997 only make substitutions if the resulting address is still
4000 Note that we cannot pass X as the object in the recursive call
4001 since the insn being processed may not allow all valid
4002 addresses. However, if we were not passed on object, we can
4003 only modify X without copying it if X will have a valid
4006 ??? Also note that this can still lose if OBJECT is an insn that
4007 has less restrictions on an address that some other insn.
4008 In that case, we will modify the shared address. This case
4009 doesn't seem very likely, though. One case where this could
4010 happen is in the case of a USE or CLOBBER reference, but we
4011 take care of that below. */
4013 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
4014 object ? object : x, 0))
4017 /* Otherwise make a copy and process that copy. We copy the entire
4018 RTL expression since it might be a PLUS which could also be
4020 *loc = x = copy_rtx (x);
4023 /* Fall through to generic unary operation case. */
4026 case STRICT_LOW_PART:
4028 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4029 case SIGN_EXTEND: case ZERO_EXTEND:
4030 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4031 case FLOAT: case FIX:
4032 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4037 case POPCOUNT: case PARITY:
4038 /* These case either have just one operand or we know that we need not
4039 check the rest of the operands. */
4045 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4046 go ahead and make the invalid one, but do it to a copy. For a REG,
4047 just make the recursive call, since there's no chance of a problem. */
4049 if ((GET_CODE (XEXP (x, 0)) == MEM
4050 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4052 || (GET_CODE (XEXP (x, 0)) == REG
4053 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4056 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4061 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4062 in front of this insn and substitute the temporary. */
4063 if ((new = instantiate_new_reg (x, &offset)) != 0)
4065 temp = plus_constant (new, offset);
4066 if (!validate_change (object, loc, temp, 0))
4072 temp = force_operand (temp, NULL_RTX);
4076 emit_insn_before (seq, object);
4077 if (! validate_change (object, loc, temp, 0)
4078 && ! validate_replace_rtx (x, temp, object))
4079 instantiate_virtual_regs_lossage (object);
4086 if (GET_CODE (XEXP (x, 0)) == REG)
4089 else if (GET_CODE (XEXP (x, 0)) == MEM)
4091 /* If we have a (addressof (mem ..)), do any instantiation inside
4092 since we know we'll be making the inside valid when we finally
4093 remove the ADDRESSOF. */
4094 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4103 /* Scan all subexpressions. */
4104 fmt = GET_RTX_FORMAT (code);
4105 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4108 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4111 else if (*fmt == 'E')
4112 for (j = 0; j < XVECLEN (x, i); j++)
4113 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4120 /* Optimization: assuming this function does not receive nonlocal gotos,
4121 delete the handlers for such, as well as the insns to establish
4122 and disestablish them. */
4125 delete_handlers (void)
4128 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4130 /* Delete the handler by turning off the flag that would
4131 prevent jump_optimize from deleting it.
4132 Also permit deletion of the nonlocal labels themselves
4133 if nothing local refers to them. */
4134 if (GET_CODE (insn) == CODE_LABEL)
4138 LABEL_PRESERVE_P (insn) = 0;
4140 /* Remove it from the nonlocal_label list, to avoid confusing
4142 for (t = nonlocal_labels, last_t = 0; t;
4143 last_t = t, t = TREE_CHAIN (t))
4144 if (DECL_RTL (TREE_VALUE (t)) == insn)
4149 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4151 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4154 if (GET_CODE (insn) == INSN)
4158 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4159 if (reg_mentioned_p (t, PATTERN (insn)))
4165 || (nonlocal_goto_stack_level != 0
4166 && reg_mentioned_p (nonlocal_goto_stack_level,
4168 delete_related_insns (insn);
4173 /* Return the first insn following those generated by `assign_parms'. */
4176 get_first_nonparm_insn (void)
4179 return NEXT_INSN (last_parm_insn);
4180 return get_insns ();
4183 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4184 This means a type for which function calls must pass an address to the
4185 function or get an address back from the function.
4186 EXP may be a type node or an expression (whose type is tested). */
4189 aggregate_value_p (tree exp, tree fntype)
4191 int i, regno, nregs;
4194 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4197 switch (TREE_CODE (fntype))
4200 fntype = get_callee_fndecl (fntype);
4201 fntype = fntype ? TREE_TYPE (fntype) : 0;
4204 fntype = TREE_TYPE (fntype);
4209 case IDENTIFIER_NODE:
4213 /* We don't expect other rtl types here. */
4217 if (TREE_CODE (type) == VOID_TYPE)
4219 if (targetm.calls.return_in_memory (type, fntype))
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 (tree fndecl)
4252 CUMULATIVE_ARGS args_so_far;
4253 /* Total space needed so far for args on the stack,
4254 given as a constant and a tree-expression. */
4255 struct args_size stack_args_size;
4256 tree fntype = TREE_TYPE (fndecl);
4257 tree fnargs = DECL_ARGUMENTS (fndecl), orig_fnargs;
4258 /* This is used for the arg pointer when referring to stack args. */
4259 rtx internal_arg_pointer;
4260 /* This is a dummy PARM_DECL that we used for the function result if
4261 the function returns a structure. */
4262 tree function_result_decl = 0;
4263 int varargs_setup = 0;
4264 int reg_parm_stack_space ATTRIBUTE_UNUSED = 0;
4265 rtx conversion_insns = 0;
4267 /* Nonzero if function takes extra anonymous args.
4268 This means the last named arg must be on the stack
4269 right before the anonymous ones. */
4271 = (TYPE_ARG_TYPES (fntype) != 0
4272 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4273 != void_type_node));
4275 current_function_stdarg = stdarg;
4277 /* If the reg that the virtual arg pointer will be translated into is
4278 not a fixed reg or is the stack pointer, make a copy of the virtual
4279 arg pointer, and address parms via the copy. The frame pointer is
4280 considered fixed even though it is not marked as such.
4282 The second time through, simply use ap to avoid generating rtx. */
4284 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4285 || ! (fixed_regs[ARG_POINTER_REGNUM]
4286 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4287 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4289 internal_arg_pointer = virtual_incoming_args_rtx;
4290 current_function_internal_arg_pointer = internal_arg_pointer;
4292 stack_args_size.constant = 0;
4293 stack_args_size.var = 0;
4295 /* If struct value address is treated as the first argument, make it so. */
4296 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
4297 && ! current_function_returns_pcc_struct
4298 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
4300 tree type = build_pointer_type (TREE_TYPE (fntype));
4302 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4304 DECL_ARG_TYPE (function_result_decl) = type;
4305 TREE_CHAIN (function_result_decl) = fnargs;
4306 fnargs = function_result_decl;
4309 orig_fnargs = fnargs;
4311 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4312 parm_reg_stack_loc = ggc_alloc_cleared (max_parm_reg * sizeof (rtx));
4314 if (SPLIT_COMPLEX_ARGS)
4315 fnargs = split_complex_args (fnargs);
4317 #ifdef REG_PARM_STACK_SPACE
4318 #ifdef MAYBE_REG_PARM_STACK_SPACE
4319 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
4321 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
4325 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4326 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4328 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, fndecl);
4331 /* We haven't yet found an argument that we must push and pretend the
4333 current_function_pretend_args_size = 0;
4335 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4339 enum machine_mode promoted_mode, passed_mode;
4340 enum machine_mode nominal_mode, promoted_nominal_mode;
4342 struct locate_and_pad_arg_data locate;
4343 int passed_pointer = 0;
4344 int did_conversion = 0;
4345 tree passed_type = DECL_ARG_TYPE (parm);
4346 tree nominal_type = TREE_TYPE (parm);
4347 int last_named = 0, named_arg;
4350 int pretend_bytes = 0;
4352 /* Set LAST_NAMED if this is last named arg before last
4358 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4359 if (DECL_NAME (tem))
4365 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4366 most machines, if this is a varargs/stdarg function, then we treat
4367 the last named arg as if it were anonymous too. */
4368 named_arg = targetm.calls.strict_argument_naming (&args_so_far) ? 1 : ! last_named;
4370 if (TREE_TYPE (parm) == error_mark_node
4371 /* This can happen after weird syntax errors
4372 or if an enum type is defined among the parms. */
4373 || TREE_CODE (parm) != PARM_DECL
4374 || passed_type == NULL)
4376 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4377 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4378 TREE_USED (parm) = 1;
4382 /* Find mode of arg as it is passed, and mode of arg
4383 as it should be during execution of this function. */
4384 passed_mode = TYPE_MODE (passed_type);
4385 nominal_mode = TYPE_MODE (nominal_type);
4387 /* If the parm's mode is VOID, its value doesn't matter,
4388 and avoid the usual things like emit_move_insn that could crash. */
4389 if (nominal_mode == VOIDmode)
4391 SET_DECL_RTL (parm, const0_rtx);
4392 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4396 /* If the parm is to be passed as a transparent union, use the
4397 type of the first field for the tests below. We have already
4398 verified that the modes are the same. */
4399 if (DECL_TRANSPARENT_UNION (parm)
4400 || (TREE_CODE (passed_type) == UNION_TYPE
4401 && TYPE_TRANSPARENT_UNION (passed_type)))
4402 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4404 /* See if this arg was passed by invisible reference. It is if
4405 it is an object whose size depends on the contents of the
4406 object itself or if the machine requires these objects be passed
4409 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (passed_type))
4410 || TREE_ADDRESSABLE (passed_type)
4411 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4412 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4413 passed_type, named_arg)
4417 passed_type = nominal_type = build_pointer_type (passed_type);
4419 passed_mode = nominal_mode = Pmode;
4421 /* See if the frontend wants to pass this by invisible reference. */
4422 else if (passed_type != nominal_type
4423 && POINTER_TYPE_P (passed_type)
4424 && TREE_TYPE (passed_type) == nominal_type)
4426 nominal_type = passed_type;
4428 passed_mode = nominal_mode = Pmode;
4431 promoted_mode = passed_mode;
4433 if (targetm.calls.promote_function_args (TREE_TYPE (fndecl)))
4435 /* Compute the mode in which the arg is actually extended to. */
4436 unsignedp = TREE_UNSIGNED (passed_type);
4437 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4440 /* Let machine desc say which reg (if any) the parm arrives in.
4441 0 means it arrives on the stack. */
4442 #ifdef FUNCTION_INCOMING_ARG
4443 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4444 passed_type, named_arg);
4446 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4447 passed_type, named_arg);
4450 if (entry_parm == 0)
4451 promoted_mode = passed_mode;
4453 /* If this is the last named parameter, do any required setup for
4454 varargs or stdargs. We need to know about the case of this being an
4455 addressable type, in which case we skip the registers it
4456 would have arrived in.
4458 For stdargs, LAST_NAMED will be set for two parameters, the one that
4459 is actually the last named, and the dummy parameter. We only
4460 want to do this action once.
4462 Also, indicate when RTL generation is to be suppressed. */
4463 if (last_named && !varargs_setup)
4465 int varargs_pretend_bytes = 0;
4466 targetm.calls.setup_incoming_varargs (&args_so_far, promoted_mode,
4468 &varargs_pretend_bytes, 0);
4471 /* If the back-end has requested extra stack space, record how
4472 much is needed. Do not change pretend_args_size otherwise
4473 since it may be nonzero from an earlier partial argument. */
4474 if (varargs_pretend_bytes > 0)
4475 current_function_pretend_args_size = varargs_pretend_bytes;
4478 /* Determine parm's home in the stack,
4479 in case it arrives in the stack or we should pretend it did.
4481 Compute the stack position and rtx where the argument arrives
4484 There is one complexity here: If this was a parameter that would
4485 have been passed in registers, but wasn't only because it is
4486 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4487 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4488 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4489 0 as it was the previous time. */
4490 in_regs = entry_parm != 0;
4491 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4494 if (!in_regs && !named_arg)
4497 targetm.calls.pretend_outgoing_varargs_named (&args_so_far);
4500 #ifdef FUNCTION_INCOMING_ARG
4501 in_regs = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4503 pretend_named) != 0;
4505 in_regs = FUNCTION_ARG (args_so_far, promoted_mode,
4507 pretend_named) != 0;
4512 /* If this parameter was passed both in registers and in the stack,
4513 use the copy on the stack. */
4514 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4517 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4520 partial = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4521 passed_type, named_arg);
4523 #ifndef MAYBE_REG_PARM_STACK_SPACE
4524 /* The caller might already have allocated stack space
4525 for the register parameters. */
4526 && reg_parm_stack_space == 0
4530 /* Part of this argument is passed in registers and part
4531 is passed on the stack. Ask the prologue code to extend
4532 the stack part so that we can recreate the full value.
4534 PRETEND_BYTES is the size of the registers we need to store.
4535 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
4536 stack space that the prologue should allocate.
4538 Internally, gcc assumes that the argument pointer is
4539 aligned to STACK_BOUNDARY bits. This is used both for
4540 alignment optimizations (see init_emit) and to locate
4541 arguments that are aligned to more than PARM_BOUNDARY
4542 bits. We must preserve this invariant by rounding
4543 CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to a stack
4545 pretend_bytes = partial * UNITS_PER_WORD;
4546 current_function_pretend_args_size
4547 = CEIL_ROUND (pretend_bytes, STACK_BYTES);
4549 /* If PRETEND_BYTES != CURRENT_FUNCTION_PRETEND_ARGS_SIZE,
4550 insert the padding before the start of the first pretend
4552 stack_args_size.constant
4553 = (current_function_pretend_args_size - pretend_bytes);
4558 memset (&locate, 0, sizeof (locate));
4559 locate_and_pad_parm (promoted_mode, passed_type, in_regs,
4560 entry_parm ? partial : 0, fndecl,
4561 &stack_args_size, &locate);
4566 /* If we're passing this arg using a reg, make its stack home
4567 the aligned stack slot. */
4569 offset_rtx = ARGS_SIZE_RTX (locate.slot_offset);
4571 offset_rtx = ARGS_SIZE_RTX (locate.offset);
4573 if (offset_rtx == const0_rtx)
4574 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4576 stack_parm = gen_rtx_MEM (promoted_mode,
4577 gen_rtx_PLUS (Pmode,
4578 internal_arg_pointer,
4581 set_mem_attributes (stack_parm, parm, 1);
4582 if (entry_parm && MEM_ATTRS (stack_parm)->align < PARM_BOUNDARY)
4583 set_mem_align (stack_parm, PARM_BOUNDARY);
4585 /* Set also REG_ATTRS if parameter was passed in a register. */
4587 set_reg_attrs_for_parm (entry_parm, stack_parm);
4590 /* If this parm was passed part in regs and part in memory,
4591 pretend it arrived entirely in memory
4592 by pushing the register-part onto the stack.
4594 In the special case of a DImode or DFmode that is split,
4595 we could put it together in a pseudoreg directly,
4596 but for now that's not worth bothering with. */
4600 /* Handle calls that pass values in multiple non-contiguous
4601 locations. The Irix 6 ABI has examples of this. */
4602 if (GET_CODE (entry_parm) == PARALLEL)
4603 emit_group_store (validize_mem (stack_parm), entry_parm,
4605 int_size_in_bytes (TREE_TYPE (parm)));
4608 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
4611 entry_parm = stack_parm;
4614 /* If we didn't decide this parm came in a register,
4615 by default it came on the stack. */
4616 if (entry_parm == 0)
4617 entry_parm = stack_parm;
4619 /* Record permanently how this parm was passed. */
4620 DECL_INCOMING_RTL (parm) = entry_parm;
4622 /* If there is actually space on the stack for this parm,
4623 count it in stack_args_size; otherwise set stack_parm to 0
4624 to indicate there is no preallocated stack slot for the parm. */
4626 if (entry_parm == stack_parm
4627 || (GET_CODE (entry_parm) == PARALLEL
4628 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4629 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4630 /* On some machines, even if a parm value arrives in a register
4631 there is still an (uninitialized) stack slot allocated for it.
4633 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4634 whether this parameter already has a stack slot allocated,
4635 because an arg block exists only if current_function_args_size
4636 is larger than some threshold, and we haven't calculated that
4637 yet. So, for now, we just assume that stack slots never exist
4639 || REG_PARM_STACK_SPACE (fndecl) > 0
4643 stack_args_size.constant += pretend_bytes + locate.size.constant;
4644 if (locate.size.var)
4645 ADD_PARM_SIZE (stack_args_size, locate.size.var);
4648 /* No stack slot was pushed for this parm. */
4651 /* Update info on where next arg arrives in registers. */
4653 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4654 passed_type, named_arg);
4656 /* If we can't trust the parm stack slot to be aligned enough
4657 for its ultimate type, don't use that slot after entry.
4658 We'll make another stack slot, if we need one. */
4660 unsigned int thisparm_boundary
4661 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4663 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4667 /* If parm was passed in memory, and we need to convert it on entry,
4668 don't store it back in that same slot. */
4669 if (entry_parm == stack_parm
4670 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4673 /* When an argument is passed in multiple locations, we can't
4674 make use of this information, but we can save some copying if
4675 the whole argument is passed in a single register. */
4676 if (GET_CODE (entry_parm) == PARALLEL
4677 && nominal_mode != BLKmode && passed_mode != BLKmode)
4679 int i, len = XVECLEN (entry_parm, 0);
4681 for (i = 0; i < len; i++)
4682 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4683 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4684 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4686 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4688 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4689 DECL_INCOMING_RTL (parm) = entry_parm;
4694 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4695 in the mode in which it arrives.
4696 STACK_PARM is an RTX for a stack slot where the parameter can live
4697 during the function (in case we want to put it there).
4698 STACK_PARM is 0 if no stack slot was pushed for it.
4700 Now output code if necessary to convert ENTRY_PARM to
4701 the type in which this function declares it,
4702 and store that result in an appropriate place,
4703 which may be a pseudo reg, may be STACK_PARM,
4704 or may be a local stack slot if STACK_PARM is 0.
4706 Set DECL_RTL to that place. */
4708 if (GET_CODE (entry_parm) == PARALLEL && nominal_mode != BLKmode
4709 && XVECLEN (entry_parm, 0) > 1)
4711 /* Reconstitute objects the size of a register or larger using
4712 register operations instead of the stack. */
4713 rtx parmreg = gen_reg_rtx (nominal_mode);
4715 if (REG_P (parmreg))
4717 emit_group_store (parmreg, entry_parm, TREE_TYPE (parm),
4718 int_size_in_bytes (TREE_TYPE (parm)));
4719 SET_DECL_RTL (parm, parmreg);
4723 if (nominal_mode == BLKmode
4724 #ifdef BLOCK_REG_PADDING
4725 || (locate.where_pad == (BYTES_BIG_ENDIAN ? upward : downward)
4726 && GET_MODE_SIZE (promoted_mode) < UNITS_PER_WORD)
4728 || GET_CODE (entry_parm) == PARALLEL)
4730 /* If a BLKmode arrives in registers, copy it to a stack slot.
4731 Handle calls that pass values in multiple non-contiguous
4732 locations. The Irix 6 ABI has examples of this. */
4733 if (GET_CODE (entry_parm) == REG
4734 || GET_CODE (entry_parm) == PARALLEL)
4736 int size = int_size_in_bytes (TREE_TYPE (parm));
4737 int size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
4740 /* Note that we will be storing an integral number of words.
4741 So we have to be careful to ensure that we allocate an
4742 integral number of words. We do this below in the
4743 assign_stack_local if space was not allocated in the argument
4744 list. If it was, this will not work if PARM_BOUNDARY is not
4745 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4746 if it becomes a problem. Exception is when BLKmode arrives
4747 with arguments not conforming to word_mode. */
4749 if (stack_parm == 0)
4751 stack_parm = assign_stack_local (BLKmode, size_stored, 0);
4752 PUT_MODE (stack_parm, GET_MODE (entry_parm));
4753 set_mem_attributes (stack_parm, parm, 1);
4755 else if (GET_CODE (entry_parm) == PARALLEL
4756 && GET_MODE(entry_parm) == BLKmode)
4758 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4761 mem = validize_mem (stack_parm);
4763 /* Handle calls that pass values in multiple non-contiguous
4764 locations. The Irix 6 ABI has examples of this. */
4765 if (GET_CODE (entry_parm) == PARALLEL)
4766 emit_group_store (mem, entry_parm, TREE_TYPE (parm), size);
4771 /* If SIZE is that of a mode no bigger than a word, just use
4772 that mode's store operation. */
4773 else if (size <= UNITS_PER_WORD)
4775 enum machine_mode mode
4776 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
4779 #ifdef BLOCK_REG_PADDING
4780 && (size == UNITS_PER_WORD
4781 || (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4782 != (BYTES_BIG_ENDIAN ? upward : downward)))
4786 rtx reg = gen_rtx_REG (mode, REGNO (entry_parm));
4787 emit_move_insn (change_address (mem, mode, 0), reg);
4790 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
4791 machine must be aligned to the left before storing
4792 to memory. Note that the previous test doesn't
4793 handle all cases (e.g. SIZE == 3). */
4794 else if (size != UNITS_PER_WORD
4795 #ifdef BLOCK_REG_PADDING
4796 && (BLOCK_REG_PADDING (mode, TREE_TYPE (parm), 1)
4804 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
4805 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
4807 x = expand_binop (word_mode, ashl_optab, reg,
4808 GEN_INT (by), 0, 1, OPTAB_WIDEN);
4809 tem = change_address (mem, word_mode, 0);
4810 emit_move_insn (tem, x);
4813 move_block_from_reg (REGNO (entry_parm), mem,
4814 size_stored / UNITS_PER_WORD);
4817 move_block_from_reg (REGNO (entry_parm), mem,
4818 size_stored / UNITS_PER_WORD);
4820 /* If parm is already bound to register pair, don't change
4822 if (! DECL_RTL_SET_P (parm))
4823 SET_DECL_RTL (parm, stack_parm);
4825 else if (! ((! optimize
4826 && ! DECL_REGISTER (parm))
4827 || TREE_SIDE_EFFECTS (parm)
4828 /* If -ffloat-store specified, don't put explicit
4829 float variables into registers. */
4830 || (flag_float_store
4831 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4832 /* Always assign pseudo to structure return or item passed
4833 by invisible reference. */
4834 || passed_pointer || parm == function_result_decl)
4836 /* Store the parm in a pseudoregister during the function, but we
4837 may need to do it in a wider mode. */
4840 unsigned int regno, regnoi = 0, regnor = 0;
4842 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4844 promoted_nominal_mode
4845 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4847 parmreg = gen_reg_rtx (promoted_nominal_mode);
4848 mark_user_reg (parmreg);
4850 /* If this was an item that we received a pointer to, set DECL_RTL
4854 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4856 set_mem_attributes (x, parm, 1);
4857 SET_DECL_RTL (parm, x);
4861 SET_DECL_RTL (parm, parmreg);
4862 maybe_set_unchanging (DECL_RTL (parm), parm);
4865 /* Copy the value into the register. */
4866 if (nominal_mode != passed_mode
4867 || promoted_nominal_mode != promoted_mode)
4870 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4871 mode, by the caller. We now have to convert it to
4872 NOMINAL_MODE, if different. However, PARMREG may be in
4873 a different mode than NOMINAL_MODE if it is being stored
4876 If ENTRY_PARM is a hard register, it might be in a register
4877 not valid for operating in its mode (e.g., an odd-numbered
4878 register for a DFmode). In that case, moves are the only
4879 thing valid, so we can't do a convert from there. This
4880 occurs when the calling sequence allow such misaligned
4883 In addition, the conversion may involve a call, which could
4884 clobber parameters which haven't been copied to pseudo
4885 registers yet. Therefore, we must first copy the parm to
4886 a pseudo reg here, and save the conversion until after all
4887 parameters have been moved. */
4889 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4891 emit_move_insn (tempreg, validize_mem (entry_parm));
4893 push_to_sequence (conversion_insns);
4894 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4896 if (GET_CODE (tempreg) == SUBREG
4897 && GET_MODE (tempreg) == nominal_mode
4898 && GET_CODE (SUBREG_REG (tempreg)) == REG
4899 && nominal_mode == passed_mode
4900 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4901 && GET_MODE_SIZE (GET_MODE (tempreg))
4902 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4904 /* The argument is already sign/zero extended, so note it
4906 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4907 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4910 /* TREE_USED gets set erroneously during expand_assignment. */
4911 save_tree_used = TREE_USED (parm);
4912 expand_assignment (parm,
4913 make_tree (nominal_type, tempreg), 0);
4914 TREE_USED (parm) = save_tree_used;
4915 conversion_insns = get_insns ();
4920 emit_move_insn (parmreg, validize_mem (entry_parm));
4922 /* If we were passed a pointer but the actual value
4923 can safely live in a register, put it in one. */
4924 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4925 /* If by-reference argument was promoted, demote it. */
4926 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4928 && ! DECL_REGISTER (parm))
4929 || TREE_SIDE_EFFECTS (parm)
4930 /* If -ffloat-store specified, don't put explicit
4931 float variables into registers. */
4932 || (flag_float_store
4933 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4935 /* We can't use nominal_mode, because it will have been set to
4936 Pmode above. We must use the actual mode of the parm. */
4937 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4938 mark_user_reg (parmreg);
4939 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4941 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4942 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4943 push_to_sequence (conversion_insns);
4944 emit_move_insn (tempreg, DECL_RTL (parm));
4946 convert_to_mode (GET_MODE (parmreg),
4949 emit_move_insn (parmreg, DECL_RTL (parm));
4950 conversion_insns = get_insns();
4955 emit_move_insn (parmreg, DECL_RTL (parm));
4956 SET_DECL_RTL (parm, parmreg);
4957 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4961 #ifdef FUNCTION_ARG_CALLEE_COPIES
4962 /* If we are passed an arg by reference and it is our responsibility
4963 to make a copy, do it now.
4964 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4965 original argument, so we must recreate them in the call to
4966 FUNCTION_ARG_CALLEE_COPIES. */
4967 /* ??? Later add code to handle the case that if the argument isn't
4968 modified, don't do the copy. */
4970 else if (passed_pointer
4971 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4972 TYPE_MODE (TREE_TYPE (passed_type)),
4973 TREE_TYPE (passed_type),
4975 && ! TREE_ADDRESSABLE (TREE_TYPE (passed_type)))
4978 tree type = TREE_TYPE (passed_type);
4980 /* This sequence may involve a library call perhaps clobbering
4981 registers that haven't been copied to pseudos yet. */
4983 push_to_sequence (conversion_insns);
4985 if (!COMPLETE_TYPE_P (type)
4986 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4987 /* This is a variable sized object. */
4988 copy = gen_rtx_MEM (BLKmode,
4989 allocate_dynamic_stack_space
4990 (expr_size (parm), NULL_RTX,
4991 TYPE_ALIGN (type)));
4993 copy = assign_stack_temp (TYPE_MODE (type),
4994 int_size_in_bytes (type), 1);
4995 set_mem_attributes (copy, parm, 1);
4997 store_expr (parm, copy, 0);
4998 emit_move_insn (parmreg, XEXP (copy, 0));
4999 conversion_insns = get_insns ();
5003 #endif /* FUNCTION_ARG_CALLEE_COPIES */
5005 /* In any case, record the parm's desired stack location
5006 in case we later discover it must live in the stack.
5008 If it is a COMPLEX value, store the stack location for both
5011 if (GET_CODE (parmreg) == CONCAT)
5012 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
5014 regno = REGNO (parmreg);
5016 if (regno >= max_parm_reg)
5019 int old_max_parm_reg = max_parm_reg;
5021 /* It's slow to expand this one register at a time,
5022 but it's also rare and we need max_parm_reg to be
5023 precisely correct. */
5024 max_parm_reg = regno + 1;
5025 new = ggc_realloc (parm_reg_stack_loc,
5026 max_parm_reg * sizeof (rtx));
5027 memset (new + old_max_parm_reg, 0,
5028 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
5029 parm_reg_stack_loc = new;
5032 if (GET_CODE (parmreg) == CONCAT)
5034 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
5036 regnor = REGNO (gen_realpart (submode, parmreg));
5037 regnoi = REGNO (gen_imagpart (submode, parmreg));
5039 if (stack_parm != 0)
5041 parm_reg_stack_loc[regnor]
5042 = gen_realpart (submode, stack_parm);
5043 parm_reg_stack_loc[regnoi]
5044 = gen_imagpart (submode, stack_parm);
5048 parm_reg_stack_loc[regnor] = 0;
5049 parm_reg_stack_loc[regnoi] = 0;
5053 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
5055 /* Mark the register as eliminable if we did no conversion
5056 and it was copied from memory at a fixed offset,
5057 and the arg pointer was not copied to a pseudo-reg.
5058 If the arg pointer is a pseudo reg or the offset formed
5059 an invalid address, such memory-equivalences
5060 as we make here would screw up life analysis for it. */
5061 if (nominal_mode == passed_mode
5064 && GET_CODE (stack_parm) == MEM
5065 && locate.offset.var == 0
5066 && reg_mentioned_p (virtual_incoming_args_rtx,
5067 XEXP (stack_parm, 0)))
5069 rtx linsn = get_last_insn ();
5072 /* Mark complex types separately. */
5073 if (GET_CODE (parmreg) == CONCAT)
5074 /* Scan backwards for the set of the real and
5076 for (sinsn = linsn; sinsn != 0;
5077 sinsn = prev_nonnote_insn (sinsn))
5079 set = single_set (sinsn);
5081 && SET_DEST (set) == regno_reg_rtx [regnoi])
5083 = gen_rtx_EXPR_LIST (REG_EQUIV,
5084 parm_reg_stack_loc[regnoi],
5087 && SET_DEST (set) == regno_reg_rtx [regnor])
5089 = gen_rtx_EXPR_LIST (REG_EQUIV,
5090 parm_reg_stack_loc[regnor],
5093 else if ((set = single_set (linsn)) != 0
5094 && SET_DEST (set) == parmreg)
5096 = gen_rtx_EXPR_LIST (REG_EQUIV,
5097 stack_parm, REG_NOTES (linsn));
5100 /* For pointer data type, suggest pointer register. */
5101 if (POINTER_TYPE_P (TREE_TYPE (parm)))
5102 mark_reg_pointer (parmreg,
5103 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5105 /* If something wants our address, try to use ADDRESSOF. */
5106 if (TREE_ADDRESSABLE (parm))
5108 /* If we end up putting something into the stack,
5109 fixup_var_refs_insns will need to make a pass over
5110 all the instructions. It looks through the pending
5111 sequences -- but it can't see the ones in the
5112 CONVERSION_INSNS, if they're not on the sequence
5113 stack. So, we go back to that sequence, just so that
5114 the fixups will happen. */
5115 push_to_sequence (conversion_insns);
5116 put_var_into_stack (parm, /*rescan=*/true);
5117 conversion_insns = get_insns ();
5123 /* Value must be stored in the stack slot STACK_PARM
5124 during function execution. */
5126 if (promoted_mode != nominal_mode)
5128 /* Conversion is required. */
5129 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
5131 emit_move_insn (tempreg, validize_mem (entry_parm));
5133 push_to_sequence (conversion_insns);
5134 entry_parm = convert_to_mode (nominal_mode, tempreg,
5135 TREE_UNSIGNED (TREE_TYPE (parm)));
5137 /* ??? This may need a big-endian conversion on sparc64. */
5138 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
5140 conversion_insns = get_insns ();
5145 if (entry_parm != stack_parm)
5147 if (stack_parm == 0)
5150 = assign_stack_local (GET_MODE (entry_parm),
5151 GET_MODE_SIZE (GET_MODE (entry_parm)),
5153 set_mem_attributes (stack_parm, parm, 1);
5156 if (promoted_mode != nominal_mode)
5158 push_to_sequence (conversion_insns);
5159 emit_move_insn (validize_mem (stack_parm),
5160 validize_mem (entry_parm));
5161 conversion_insns = get_insns ();
5165 emit_move_insn (validize_mem (stack_parm),
5166 validize_mem (entry_parm));
5169 SET_DECL_RTL (parm, stack_parm);
5173 if (SPLIT_COMPLEX_ARGS && fnargs != orig_fnargs)
5175 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm))
5177 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE)
5180 gen_rtx_CONCAT (DECL_MODE (parm),
5182 DECL_RTL (TREE_CHAIN (fnargs))));
5183 DECL_INCOMING_RTL (parm)
5184 = gen_rtx_CONCAT (DECL_MODE (parm),
5185 DECL_INCOMING_RTL (fnargs),
5186 DECL_INCOMING_RTL (TREE_CHAIN (fnargs)));
5187 fnargs = TREE_CHAIN (fnargs);
5191 SET_DECL_RTL (parm, DECL_RTL (fnargs));
5192 DECL_INCOMING_RTL (parm) = DECL_INCOMING_RTL (fnargs);
5194 fnargs = TREE_CHAIN (fnargs);
5198 /* Output all parameter conversion instructions (possibly including calls)
5199 now that all parameters have been copied out of hard registers. */
5200 emit_insn (conversion_insns);
5202 /* If we are receiving a struct value address as the first argument, set up
5203 the RTL for the function result. As this might require code to convert
5204 the transmitted address to Pmode, we do this here to ensure that possible
5205 preliminary conversions of the address have been emitted already. */
5206 if (function_result_decl)
5208 tree result = DECL_RESULT (fndecl);
5209 rtx addr = DECL_RTL (function_result_decl);
5212 addr = convert_memory_address (Pmode, addr);
5213 x = gen_rtx_MEM (DECL_MODE (result), addr);
5214 set_mem_attributes (x, result, 1);
5215 SET_DECL_RTL (result, x);
5218 last_parm_insn = get_last_insn ();
5220 current_function_args_size = stack_args_size.constant;
5222 /* Adjust function incoming argument size for alignment and
5225 #ifdef REG_PARM_STACK_SPACE
5226 #ifndef MAYBE_REG_PARM_STACK_SPACE
5227 current_function_args_size = MAX (current_function_args_size,
5228 REG_PARM_STACK_SPACE (fndecl));
5232 current_function_args_size
5233 = ((current_function_args_size + STACK_BYTES - 1)
5234 / STACK_BYTES) * STACK_BYTES;
5236 #ifdef ARGS_GROW_DOWNWARD
5237 current_function_arg_offset_rtx
5238 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5239 : expand_expr (size_diffop (stack_args_size.var,
5240 size_int (-stack_args_size.constant)),
5241 NULL_RTX, VOIDmode, 0));
5243 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5246 /* See how many bytes, if any, of its args a function should try to pop
5249 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5250 current_function_args_size);
5252 /* For stdarg.h function, save info about
5253 regs and stack space used by the named args. */
5255 current_function_args_info = args_so_far;
5257 /* Set the rtx used for the function return value. Put this in its
5258 own variable so any optimizers that need this information don't have
5259 to include tree.h. Do this here so it gets done when an inlined
5260 function gets output. */
5262 current_function_return_rtx
5263 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5264 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5266 /* If scalar return value was computed in a pseudo-reg, or was a named
5267 return value that got dumped to the stack, copy that to the hard
5269 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5271 tree decl_result = DECL_RESULT (fndecl);
5272 rtx decl_rtl = DECL_RTL (decl_result);
5274 if (REG_P (decl_rtl)
5275 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5276 : DECL_REGISTER (decl_result))
5280 #ifdef FUNCTION_OUTGOING_VALUE
5281 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5284 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5287 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5288 /* The delay slot scheduler assumes that current_function_return_rtx
5289 holds the hard register containing the return value, not a
5290 temporary pseudo. */
5291 current_function_return_rtx = real_decl_rtl;
5296 /* If ARGS contains entries with complex types, split the entry into two
5297 entries of the component type. Return a new list of substitutions are
5298 needed, else the old list. */
5301 split_complex_args (tree args)
5305 /* Before allocating memory, check for the common case of no complex. */
5306 for (p = args; p; p = TREE_CHAIN (p))
5307 if (TREE_CODE (TREE_TYPE (p)) == COMPLEX_TYPE)
5312 args = copy_list (args);
5314 for (p = args; p; p = TREE_CHAIN (p))
5316 tree type = TREE_TYPE (p);
5317 if (TREE_CODE (type) == COMPLEX_TYPE)
5320 tree subtype = TREE_TYPE (type);
5322 /* Rewrite the PARM_DECL's type with its component. */
5323 TREE_TYPE (p) = subtype;
5324 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
5325 DECL_MODE (p) = VOIDmode;
5326 DECL_SIZE (p) = NULL;
5327 DECL_SIZE_UNIT (p) = NULL;
5330 /* Build a second synthetic decl. */
5331 decl = build_decl (PARM_DECL, NULL_TREE, subtype);
5332 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
5333 layout_decl (decl, 0);
5335 /* Splice it in; skip the new decl. */
5336 TREE_CHAIN (decl) = TREE_CHAIN (p);
5337 TREE_CHAIN (p) = decl;
5345 /* Indicate whether REGNO is an incoming argument to the current function
5346 that was promoted to a wider mode. If so, return the RTX for the
5347 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5348 that REGNO is promoted from and whether the promotion was signed or
5352 promoted_input_arg (unsigned int regno, enum machine_mode *pmode, int *punsignedp)
5356 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5357 arg = TREE_CHAIN (arg))
5358 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5359 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5360 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5362 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5363 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5365 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5366 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5367 && mode != DECL_MODE (arg))
5369 *pmode = DECL_MODE (arg);
5370 *punsignedp = unsignedp;
5371 return DECL_INCOMING_RTL (arg);
5379 /* Compute the size and offset from the start of the stacked arguments for a
5380 parm passed in mode PASSED_MODE and with type TYPE.
5382 INITIAL_OFFSET_PTR points to the current offset into the stacked
5385 The starting offset and size for this parm are returned in
5386 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
5387 nonzero, the offset is that of stack slot, which is returned in
5388 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
5389 padding required from the initial offset ptr to the stack slot.
5391 IN_REGS is nonzero if the argument will be passed in registers. It will
5392 never be set if REG_PARM_STACK_SPACE is not defined.
5394 FNDECL is the function in which the argument was defined.
5396 There are two types of rounding that are done. The first, controlled by
5397 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5398 list to be aligned to the specific boundary (in bits). This rounding
5399 affects the initial and starting offsets, but not the argument size.
5401 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5402 optionally rounds the size of the parm to PARM_BOUNDARY. The
5403 initial offset is not affected by this rounding, while the size always
5404 is and the starting offset may be. */
5406 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
5407 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
5408 callers pass in the total size of args so far as
5409 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
5412 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
5413 int partial, tree fndecl ATTRIBUTE_UNUSED,
5414 struct args_size *initial_offset_ptr,
5415 struct locate_and_pad_arg_data *locate)
5418 enum direction where_pad;
5420 int reg_parm_stack_space = 0;
5421 int part_size_in_regs;
5423 #ifdef REG_PARM_STACK_SPACE
5424 #ifdef MAYBE_REG_PARM_STACK_SPACE
5425 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5427 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5430 /* If we have found a stack parm before we reach the end of the
5431 area reserved for registers, skip that area. */
5434 if (reg_parm_stack_space > 0)
5436 if (initial_offset_ptr->var)
5438 initial_offset_ptr->var
5439 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5440 ssize_int (reg_parm_stack_space));
5441 initial_offset_ptr->constant = 0;
5443 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5444 initial_offset_ptr->constant = reg_parm_stack_space;
5447 #endif /* REG_PARM_STACK_SPACE */
5449 part_size_in_regs = 0;
5450 if (reg_parm_stack_space == 0)
5451 part_size_in_regs = ((partial * UNITS_PER_WORD)
5452 / (PARM_BOUNDARY / BITS_PER_UNIT)
5453 * (PARM_BOUNDARY / BITS_PER_UNIT));
5456 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5457 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5458 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5459 locate->where_pad = where_pad;
5461 #ifdef ARGS_GROW_DOWNWARD
5462 locate->slot_offset.constant = -initial_offset_ptr->constant;
5463 if (initial_offset_ptr->var)
5464 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
5465 initial_offset_ptr->var);
5469 if (where_pad != none
5470 && (!host_integerp (sizetree, 1)
5471 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5472 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
5473 SUB_PARM_SIZE (locate->slot_offset, s2);
5476 locate->slot_offset.constant += part_size_in_regs;
5479 #ifdef REG_PARM_STACK_SPACE
5480 || REG_PARM_STACK_SPACE (fndecl) > 0
5483 pad_to_arg_alignment (&locate->slot_offset, boundary,
5484 &locate->alignment_pad);
5486 locate->size.constant = (-initial_offset_ptr->constant
5487 - locate->slot_offset.constant);
5488 if (initial_offset_ptr->var)
5489 locate->size.var = size_binop (MINUS_EXPR,
5490 size_binop (MINUS_EXPR,
5492 initial_offset_ptr->var),
5493 locate->slot_offset.var);
5495 /* Pad_below needs the pre-rounded size to know how much to pad
5497 locate->offset = locate->slot_offset;
5498 if (where_pad == downward)
5499 pad_below (&locate->offset, passed_mode, sizetree);
5501 #else /* !ARGS_GROW_DOWNWARD */
5503 #ifdef REG_PARM_STACK_SPACE
5504 || REG_PARM_STACK_SPACE (fndecl) > 0
5507 pad_to_arg_alignment (initial_offset_ptr, boundary,
5508 &locate->alignment_pad);
5509 locate->slot_offset = *initial_offset_ptr;
5511 #ifdef PUSH_ROUNDING
5512 if (passed_mode != BLKmode)
5513 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5516 /* Pad_below needs the pre-rounded size to know how much to pad below
5517 so this must be done before rounding up. */
5518 locate->offset = locate->slot_offset;
5519 if (where_pad == downward)
5520 pad_below (&locate->offset, passed_mode, sizetree);
5522 if (where_pad != none
5523 && (!host_integerp (sizetree, 1)
5524 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5525 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5527 ADD_PARM_SIZE (locate->size, sizetree);
5529 locate->size.constant -= part_size_in_regs;
5530 #endif /* ARGS_GROW_DOWNWARD */
5533 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5534 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5537 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
5538 struct args_size *alignment_pad)
5540 tree save_var = NULL_TREE;
5541 HOST_WIDE_INT save_constant = 0;
5542 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5543 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
5545 #ifdef SPARC_STACK_BOUNDARY_HACK
5546 /* The sparc port has a bug. It sometimes claims a STACK_BOUNDARY
5547 higher than the real alignment of %sp. However, when it does this,
5548 the alignment of %sp+STACK_POINTER_OFFSET will be STACK_BOUNDARY.
5549 This is a temporary hack while the sparc port is fixed. */
5550 if (SPARC_STACK_BOUNDARY_HACK)
5554 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5556 save_var = offset_ptr->var;
5557 save_constant = offset_ptr->constant;
5560 alignment_pad->var = NULL_TREE;
5561 alignment_pad->constant = 0;
5563 if (boundary > BITS_PER_UNIT)
5565 if (offset_ptr->var)
5567 tree sp_offset_tree = ssize_int (sp_offset);
5568 tree offset = size_binop (PLUS_EXPR,
5569 ARGS_SIZE_TREE (*offset_ptr),
5571 #ifdef ARGS_GROW_DOWNWARD
5572 tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
5574 tree rounded = round_up (offset, boundary / BITS_PER_UNIT);
5577 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
5578 /* ARGS_SIZE_TREE includes constant term. */
5579 offset_ptr->constant = 0;
5580 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5581 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5586 offset_ptr->constant = -sp_offset +
5587 #ifdef ARGS_GROW_DOWNWARD
5588 FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
5590 CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
5592 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5593 alignment_pad->constant = offset_ptr->constant - save_constant;
5599 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
5601 if (passed_mode != BLKmode)
5603 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5604 offset_ptr->constant
5605 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5606 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5607 - GET_MODE_SIZE (passed_mode));
5611 if (TREE_CODE (sizetree) != INTEGER_CST
5612 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5614 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5615 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5617 ADD_PARM_SIZE (*offset_ptr, s2);
5618 SUB_PARM_SIZE (*offset_ptr, sizetree);
5623 /* Walk the tree of blocks describing the binding levels within a function
5624 and warn about uninitialized variables.
5625 This is done after calling flow_analysis and before global_alloc
5626 clobbers the pseudo-regs to hard regs. */
5629 uninitialized_vars_warning (tree block)
5632 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5634 if (warn_uninitialized
5635 && TREE_CODE (decl) == VAR_DECL
5636 /* These warnings are unreliable for and aggregates
5637 because assigning the fields one by one can fail to convince
5638 flow.c that the entire aggregate was initialized.
5639 Unions are troublesome because members may be shorter. */
5640 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5641 && DECL_RTL (decl) != 0
5642 && GET_CODE (DECL_RTL (decl)) == REG
5643 /* Global optimizations can make it difficult to determine if a
5644 particular variable has been initialized. However, a VAR_DECL
5645 with a nonzero DECL_INITIAL had an initializer, so do not
5646 claim it is potentially uninitialized.
5648 When the DECL_INITIAL is NULL call the language hook to tell us
5649 if we want to warn. */
5650 && (DECL_INITIAL (decl) == NULL_TREE || lang_hooks.decl_uninit (decl))
5651 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5652 warning ("%J'%D' might be used uninitialized in this function",
5655 && TREE_CODE (decl) == VAR_DECL
5656 && DECL_RTL (decl) != 0
5657 && GET_CODE (DECL_RTL (decl)) == REG
5658 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5659 warning ("%Jvariable '%D' might be clobbered by `longjmp' or `vfork'",
5662 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5663 uninitialized_vars_warning (sub);
5666 /* Do the appropriate part of uninitialized_vars_warning
5667 but for arguments instead of local variables. */
5670 setjmp_args_warning (void)
5673 for (decl = DECL_ARGUMENTS (current_function_decl);
5674 decl; decl = TREE_CHAIN (decl))
5675 if (DECL_RTL (decl) != 0
5676 && GET_CODE (DECL_RTL (decl)) == REG
5677 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5678 warning ("%Jargument '%D' might be clobbered by `longjmp' or `vfork'",
5682 /* If this function call setjmp, put all vars into the stack
5683 unless they were declared `register'. */
5686 setjmp_protect (tree block)
5689 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5690 if ((TREE_CODE (decl) == VAR_DECL
5691 || TREE_CODE (decl) == PARM_DECL)
5692 && DECL_RTL (decl) != 0
5693 && (GET_CODE (DECL_RTL (decl)) == REG
5694 || (GET_CODE (DECL_RTL (decl)) == MEM
5695 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5696 /* If this variable came from an inline function, it must be
5697 that its life doesn't overlap the setjmp. If there was a
5698 setjmp in the function, it would already be in memory. We
5699 must exclude such variable because their DECL_RTL might be
5700 set to strange things such as virtual_stack_vars_rtx. */
5701 && ! DECL_FROM_INLINE (decl)
5703 #ifdef NON_SAVING_SETJMP
5704 /* If longjmp doesn't restore the registers,
5705 don't put anything in them. */
5709 ! DECL_REGISTER (decl)))
5710 put_var_into_stack (decl, /*rescan=*/true);
5711 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5712 setjmp_protect (sub);
5715 /* Like the previous function, but for args instead of local variables. */
5718 setjmp_protect_args (void)
5721 for (decl = DECL_ARGUMENTS (current_function_decl);
5722 decl; decl = TREE_CHAIN (decl))
5723 if ((TREE_CODE (decl) == VAR_DECL
5724 || TREE_CODE (decl) == PARM_DECL)
5725 && DECL_RTL (decl) != 0
5726 && (GET_CODE (DECL_RTL (decl)) == REG
5727 || (GET_CODE (DECL_RTL (decl)) == MEM
5728 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5730 /* If longjmp doesn't restore the registers,
5731 don't put anything in them. */
5732 #ifdef NON_SAVING_SETJMP
5736 ! DECL_REGISTER (decl)))
5737 put_var_into_stack (decl, /*rescan=*/true);
5740 /* Return the context-pointer register corresponding to DECL,
5741 or 0 if it does not need one. */
5744 lookup_static_chain (tree decl)
5746 tree context = decl_function_context (decl);
5750 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5753 /* We treat inline_function_decl as an alias for the current function
5754 because that is the inline function whose vars, types, etc.
5755 are being merged into the current function.
5756 See expand_inline_function. */
5757 if (context == current_function_decl || context == inline_function_decl)
5758 return virtual_stack_vars_rtx;
5760 for (link = context_display; link; link = TREE_CHAIN (link))
5761 if (TREE_PURPOSE (link) == context)
5762 return RTL_EXPR_RTL (TREE_VALUE (link));
5767 /* Convert a stack slot address ADDR for variable VAR
5768 (from a containing function)
5769 into an address valid in this function (using a static chain). */
5772 fix_lexical_addr (rtx addr, tree var)
5775 HOST_WIDE_INT displacement;
5776 tree context = decl_function_context (var);
5777 struct function *fp;
5780 /* If this is the present function, we need not do anything. */
5781 if (context == current_function_decl || context == inline_function_decl)
5784 fp = find_function_data (context);
5786 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5787 addr = XEXP (XEXP (addr, 0), 0);
5789 /* Decode given address as base reg plus displacement. */
5790 if (GET_CODE (addr) == REG)
5791 basereg = addr, displacement = 0;
5792 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5793 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5797 /* We accept vars reached via the containing function's
5798 incoming arg pointer and via its stack variables pointer. */
5799 if (basereg == fp->internal_arg_pointer)
5801 /* If reached via arg pointer, get the arg pointer value
5802 out of that function's stack frame.
5804 There are two cases: If a separate ap is needed, allocate a
5805 slot in the outer function for it and dereference it that way.
5806 This is correct even if the real ap is actually a pseudo.
5807 Otherwise, just adjust the offset from the frame pointer to
5810 #ifdef NEED_SEPARATE_AP
5813 addr = get_arg_pointer_save_area (fp);
5814 addr = fix_lexical_addr (XEXP (addr, 0), var);
5815 addr = memory_address (Pmode, addr);
5817 base = gen_rtx_MEM (Pmode, addr);
5818 set_mem_alias_set (base, get_frame_alias_set ());
5819 base = copy_to_reg (base);
5821 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5822 base = lookup_static_chain (var);
5826 else if (basereg == virtual_stack_vars_rtx)
5828 /* This is the same code as lookup_static_chain, duplicated here to
5829 avoid an extra call to decl_function_context. */
5832 for (link = context_display; link; link = TREE_CHAIN (link))
5833 if (TREE_PURPOSE (link) == context)
5835 base = RTL_EXPR_RTL (TREE_VALUE (link));
5843 /* Use same offset, relative to appropriate static chain or argument
5845 return plus_constant (base, displacement);
5848 /* Return the address of the trampoline for entering nested fn FUNCTION.
5849 If necessary, allocate a trampoline (in the stack frame)
5850 and emit rtl to initialize its contents (at entry to this function). */
5853 trampoline_address (tree function)
5858 struct function *fp;
5861 /* Find an existing trampoline and return it. */
5862 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5863 if (TREE_PURPOSE (link) == function)
5865 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5867 for (fp = outer_function_chain; fp; fp = fp->outer)
5868 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5869 if (TREE_PURPOSE (link) == function)
5871 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5873 return adjust_trampoline_addr (tramp);
5876 /* None exists; we must make one. */
5878 /* Find the `struct function' for the function containing FUNCTION. */
5880 fn_context = decl_function_context (function);
5881 if (fn_context != current_function_decl
5882 && fn_context != inline_function_decl)
5883 fp = find_function_data (fn_context);
5885 /* Allocate run-time space for this trampoline. */
5886 /* If rounding needed, allocate extra space
5887 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5888 #define TRAMPOLINE_REAL_SIZE \
5889 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5890 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5892 /* Record the trampoline for reuse and note it for later initialization
5893 by expand_function_end. */
5896 rtlexp = make_node (RTL_EXPR);
5897 RTL_EXPR_RTL (rtlexp) = tramp;
5898 fp->x_trampoline_list = tree_cons (function, rtlexp,
5899 fp->x_trampoline_list);
5903 /* Make the RTL_EXPR node temporary, not momentary, so that the
5904 trampoline_list doesn't become garbage. */
5905 rtlexp = make_node (RTL_EXPR);
5907 RTL_EXPR_RTL (rtlexp) = tramp;
5908 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5911 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5912 return adjust_trampoline_addr (tramp);
5915 /* Given a trampoline address,
5916 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5919 round_trampoline_addr (rtx tramp)
5921 /* Round address up to desired boundary. */
5922 rtx temp = gen_reg_rtx (Pmode);
5923 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
5924 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5926 temp = expand_simple_binop (Pmode, PLUS, tramp, addend,
5927 temp, 0, OPTAB_LIB_WIDEN);
5928 tramp = expand_simple_binop (Pmode, AND, temp, mask,
5929 temp, 0, OPTAB_LIB_WIDEN);
5934 /* Given a trampoline address, round it then apply any
5935 platform-specific adjustments so that the result can be used for a
5939 adjust_trampoline_addr (rtx tramp)
5941 tramp = round_trampoline_addr (tramp);
5942 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5943 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5948 /* Put all this function's BLOCK nodes including those that are chained
5949 onto the first block into a vector, and return it.
5950 Also store in each NOTE for the beginning or end of a block
5951 the index of that block in the vector.
5952 The arguments are BLOCK, the chain of top-level blocks of the function,
5953 and INSNS, the insn chain of the function. */
5956 identify_blocks (void)
5959 tree *block_vector, *last_block_vector;
5961 tree block = DECL_INITIAL (current_function_decl);
5966 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5967 depth-first order. */
5968 block_vector = get_block_vector (block, &n_blocks);
5969 block_stack = xmalloc (n_blocks * sizeof (tree));
5971 last_block_vector = identify_blocks_1 (get_insns (),
5973 block_vector + n_blocks,
5976 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5977 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5978 if (0 && last_block_vector != block_vector + n_blocks)
5981 free (block_vector);
5985 /* Subroutine of identify_blocks. Do the block substitution on the
5986 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5988 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5989 BLOCK_VECTOR is incremented for each block seen. */
5992 identify_blocks_1 (rtx insns, tree *block_vector, tree *end_block_vector,
5993 tree *orig_block_stack)
5996 tree *block_stack = orig_block_stack;
5998 for (insn = insns; insn; insn = NEXT_INSN (insn))
6000 if (GET_CODE (insn) == NOTE)
6002 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
6006 /* If there are more block notes than BLOCKs, something
6008 if (block_vector == end_block_vector)
6011 b = *block_vector++;
6012 NOTE_BLOCK (insn) = b;
6015 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
6017 /* If there are more NOTE_INSN_BLOCK_ENDs than
6018 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
6019 if (block_stack == orig_block_stack)
6022 NOTE_BLOCK (insn) = *--block_stack;
6025 else if (GET_CODE (insn) == CALL_INSN
6026 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
6028 rtx cp = PATTERN (insn);
6030 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
6031 end_block_vector, block_stack);
6033 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
6034 end_block_vector, block_stack);
6036 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
6037 end_block_vector, block_stack);
6041 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
6042 something is badly wrong. */
6043 if (block_stack != orig_block_stack)
6046 return block_vector;
6049 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
6050 and create duplicate blocks. */
6051 /* ??? Need an option to either create block fragments or to create
6052 abstract origin duplicates of a source block. It really depends
6053 on what optimization has been performed. */
6056 reorder_blocks (void)
6058 tree block = DECL_INITIAL (current_function_decl);
6059 varray_type block_stack;
6061 if (block == NULL_TREE)
6064 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
6066 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
6067 reorder_blocks_0 (block);
6069 /* Prune the old trees away, so that they don't get in the way. */
6070 BLOCK_SUBBLOCKS (block) = NULL_TREE;
6071 BLOCK_CHAIN (block) = NULL_TREE;
6073 /* Recreate the block tree from the note nesting. */
6074 reorder_blocks_1 (get_insns (), block, &block_stack);
6075 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
6077 /* Remove deleted blocks from the block fragment chains. */
6078 reorder_fix_fragments (block);
6081 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
6084 reorder_blocks_0 (tree block)
6088 TREE_ASM_WRITTEN (block) = 0;
6089 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
6090 block = BLOCK_CHAIN (block);
6095 reorder_blocks_1 (rtx insns, tree current_block, varray_type *p_block_stack)
6099 for (insn = insns; insn; insn = NEXT_INSN (insn))
6101 if (GET_CODE (insn) == NOTE)
6103 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
6105 tree block = NOTE_BLOCK (insn);
6107 /* If we have seen this block before, that means it now
6108 spans multiple address regions. Create a new fragment. */
6109 if (TREE_ASM_WRITTEN (block))
6111 tree new_block = copy_node (block);
6114 origin = (BLOCK_FRAGMENT_ORIGIN (block)
6115 ? BLOCK_FRAGMENT_ORIGIN (block)
6117 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
6118 BLOCK_FRAGMENT_CHAIN (new_block)
6119 = BLOCK_FRAGMENT_CHAIN (origin);
6120 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
6122 NOTE_BLOCK (insn) = new_block;
6126 BLOCK_SUBBLOCKS (block) = 0;
6127 TREE_ASM_WRITTEN (block) = 1;
6128 /* When there's only one block for the entire function,
6129 current_block == block and we mustn't do this, it
6130 will cause infinite recursion. */
6131 if (block != current_block)
6133 BLOCK_SUPERCONTEXT (block) = current_block;
6134 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
6135 BLOCK_SUBBLOCKS (current_block) = block;
6136 current_block = block;
6138 VARRAY_PUSH_TREE (*p_block_stack, block);
6140 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
6142 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
6143 VARRAY_POP (*p_block_stack);
6144 BLOCK_SUBBLOCKS (current_block)
6145 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
6146 current_block = BLOCK_SUPERCONTEXT (current_block);
6149 else if (GET_CODE (insn) == CALL_INSN
6150 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
6152 rtx cp = PATTERN (insn);
6153 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
6155 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
6157 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
6162 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
6163 appears in the block tree, select one of the fragments to become
6164 the new origin block. */
6167 reorder_fix_fragments (tree block)
6171 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
6172 tree new_origin = NULL_TREE;
6176 if (! TREE_ASM_WRITTEN (dup_origin))
6178 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
6180 /* Find the first of the remaining fragments. There must
6181 be at least one -- the current block. */
6182 while (! TREE_ASM_WRITTEN (new_origin))
6183 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
6184 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
6187 else if (! dup_origin)
6190 /* Re-root the rest of the fragments to the new origin. In the
6191 case that DUP_ORIGIN was null, that means BLOCK was the origin
6192 of a chain of fragments and we want to remove those fragments
6193 that didn't make it to the output. */
6196 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
6201 if (TREE_ASM_WRITTEN (chain))
6203 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
6205 pp = &BLOCK_FRAGMENT_CHAIN (chain);
6207 chain = BLOCK_FRAGMENT_CHAIN (chain);
6212 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
6213 block = BLOCK_CHAIN (block);
6217 /* Reverse the order of elements in the chain T of blocks,
6218 and return the new head of the chain (old last element). */
6221 blocks_nreverse (tree t)
6223 tree prev = 0, decl, next;
6224 for (decl = t; decl; decl = next)
6226 next = BLOCK_CHAIN (decl);
6227 BLOCK_CHAIN (decl) = prev;
6233 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6234 non-NULL, list them all into VECTOR, in a depth-first preorder
6235 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6239 all_blocks (tree block, tree *vector)
6245 TREE_ASM_WRITTEN (block) = 0;
6247 /* Record this block. */
6249 vector[n_blocks] = block;
6253 /* Record the subblocks, and their subblocks... */
6254 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6255 vector ? vector + n_blocks : 0);
6256 block = BLOCK_CHAIN (block);
6262 /* Return a vector containing all the blocks rooted at BLOCK. The
6263 number of elements in the vector is stored in N_BLOCKS_P. The
6264 vector is dynamically allocated; it is the caller's responsibility
6265 to call `free' on the pointer returned. */
6268 get_block_vector (tree block, int *n_blocks_p)
6272 *n_blocks_p = all_blocks (block, NULL);
6273 block_vector = xmalloc (*n_blocks_p * sizeof (tree));
6274 all_blocks (block, block_vector);
6276 return block_vector;
6279 static GTY(()) int next_block_index = 2;
6281 /* Set BLOCK_NUMBER for all the blocks in FN. */
6284 number_blocks (tree fn)
6290 /* For SDB and XCOFF debugging output, we start numbering the blocks
6291 from 1 within each function, rather than keeping a running
6293 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6294 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6295 next_block_index = 1;
6298 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6300 /* The top-level BLOCK isn't numbered at all. */
6301 for (i = 1; i < n_blocks; ++i)
6302 /* We number the blocks from two. */
6303 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6305 free (block_vector);
6310 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6313 debug_find_var_in_block_tree (tree var, tree block)
6317 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6321 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6323 tree ret = debug_find_var_in_block_tree (var, t);
6331 /* Allocate a function structure for FNDECL and set its contents
6335 allocate_struct_function (tree fndecl)
6339 cfun = ggc_alloc_cleared (sizeof (struct function));
6341 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6343 cfun->stack_alignment_needed = STACK_BOUNDARY;
6344 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6346 current_function_funcdef_no = funcdef_no++;
6348 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
6350 init_stmt_for_function ();
6351 init_eh_for_function ();
6354 init_varasm_status (cfun);
6356 (*lang_hooks.function.init) (cfun);
6357 if (init_machine_status)
6358 cfun->machine = (*init_machine_status) ();
6363 DECL_SAVED_INSNS (fndecl) = cfun;
6364 cfun->decl = fndecl;
6366 current_function_name = (*lang_hooks.decl_printable_name) (fndecl, 2);
6368 result = DECL_RESULT (fndecl);
6369 if (aggregate_value_p (result, fndecl))
6371 #ifdef PCC_STATIC_STRUCT_RETURN
6372 current_function_returns_pcc_struct = 1;
6374 current_function_returns_struct = 1;
6377 current_function_returns_pointer = POINTER_TYPE_P (TREE_TYPE (result));
6379 current_function_needs_context
6380 = (decl_function_context (current_function_decl) != 0
6381 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6384 /* Reset cfun, and other non-struct-function variables to defaults as
6385 appropriate for emitting rtl at the start of a function. */
6388 prepare_function_start (tree fndecl)
6390 if (fndecl && DECL_SAVED_INSNS (fndecl))
6391 cfun = DECL_SAVED_INSNS (fndecl);
6393 allocate_struct_function (fndecl);
6395 cse_not_expected = ! optimize;
6397 /* Caller save not needed yet. */
6398 caller_save_needed = 0;
6400 /* We haven't done register allocation yet. */
6403 /* Indicate that we need to distinguish between the return value of the
6404 present function and the return value of a function being called. */
6405 rtx_equal_function_value_matters = 1;
6407 /* Indicate that we have not instantiated virtual registers yet. */
6408 virtuals_instantiated = 0;
6410 /* Indicate that we want CONCATs now. */
6411 generating_concat_p = 1;
6413 /* Indicate we have no need of a frame pointer yet. */
6414 frame_pointer_needed = 0;
6417 /* Initialize the rtl expansion mechanism so that we can do simple things
6418 like generate sequences. This is used to provide a context during global
6419 initialization of some passes. */
6421 init_dummy_function_start (void)
6423 prepare_function_start (NULL);
6426 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6427 and initialize static variables for generating RTL for the statements
6431 init_function_start (tree subr)
6433 prepare_function_start (subr);
6435 /* Within function body, compute a type's size as soon it is laid out. */
6436 immediate_size_expand++;
6438 /* Prevent ever trying to delete the first instruction of a
6439 function. Also tell final how to output a linenum before the
6440 function prologue. Note linenums could be missing, e.g. when
6441 compiling a Java .class file. */
6442 if (DECL_SOURCE_LINE (subr))
6443 emit_line_note (DECL_SOURCE_LOCATION (subr));
6445 /* Make sure first insn is a note even if we don't want linenums.
6446 This makes sure the first insn will never be deleted.
6447 Also, final expects a note to appear there. */
6448 emit_note (NOTE_INSN_DELETED);
6450 /* Warn if this value is an aggregate type,
6451 regardless of which calling convention we are using for it. */
6452 if (warn_aggregate_return
6453 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6454 warning ("function returns an aggregate");
6457 /* Make sure all values used by the optimization passes have sane
6460 init_function_for_compilation (void)
6464 /* No prologue/epilogue insns yet. */
6465 VARRAY_GROW (prologue, 0);
6466 VARRAY_GROW (epilogue, 0);
6467 VARRAY_GROW (sibcall_epilogue, 0);
6470 /* Expand a call to __main at the beginning of a possible main function. */
6472 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6473 #undef HAS_INIT_SECTION
6474 #define HAS_INIT_SECTION
6478 expand_main_function (void)
6480 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6481 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6483 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6487 /* Forcibly align the stack. */
6488 #ifdef STACK_GROWS_DOWNWARD
6489 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6490 stack_pointer_rtx, 1, OPTAB_WIDEN);
6492 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6493 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6494 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6495 stack_pointer_rtx, 1, OPTAB_WIDEN);
6497 if (tmp != stack_pointer_rtx)
6498 emit_move_insn (stack_pointer_rtx, tmp);
6500 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6501 tmp = force_reg (Pmode, const0_rtx);
6502 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6506 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6507 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6510 emit_insn_before (seq, tmp);
6516 #ifndef HAS_INIT_SECTION
6517 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
6521 /* The PENDING_SIZES represent the sizes of variable-sized types.
6522 Create RTL for the various sizes now (using temporary variables),
6523 so that we can refer to the sizes from the RTL we are generating
6524 for the current function. The PENDING_SIZES are a TREE_LIST. The
6525 TREE_VALUE of each node is a SAVE_EXPR. */
6528 expand_pending_sizes (tree pending_sizes)
6532 /* Evaluate now the sizes of any types declared among the arguments. */
6533 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6535 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6536 /* Flush the queue in case this parameter declaration has
6542 /* Start the RTL for a new function, and set variables used for
6544 SUBR is the FUNCTION_DECL node.
6545 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6546 the function's parameters, which must be run at any return statement. */
6549 expand_function_start (tree subr, int parms_have_cleanups)
6552 rtx last_ptr = NULL_RTX;
6554 /* Make sure volatile mem refs aren't considered
6555 valid operands of arithmetic insns. */
6556 init_recog_no_volatile ();
6558 current_function_instrument_entry_exit
6559 = (flag_instrument_function_entry_exit
6560 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6562 current_function_profile
6564 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6566 current_function_limit_stack
6567 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6569 /* If function gets a static chain arg, store it in the stack frame.
6570 Do this first, so it gets the first stack slot offset. */
6571 if (current_function_needs_context)
6573 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6575 /* Delay copying static chain if it is not a register to avoid
6576 conflicts with regs used for parameters. */
6577 if (! SMALL_REGISTER_CLASSES
6578 || GET_CODE (static_chain_incoming_rtx) == REG)
6579 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6582 /* If the parameters of this function need cleaning up, get a label
6583 for the beginning of the code which executes those cleanups. This must
6584 be done before doing anything with return_label. */
6585 if (parms_have_cleanups)
6586 cleanup_label = gen_label_rtx ();
6590 /* Make the label for return statements to jump to. Do not special
6591 case machines with special return instructions -- they will be
6592 handled later during jump, ifcvt, or epilogue creation. */
6593 return_label = gen_label_rtx ();
6595 /* Initialize rtx used to return the value. */
6596 /* Do this before assign_parms so that we copy the struct value address
6597 before any library calls that assign parms might generate. */
6599 /* Decide whether to return the value in memory or in a register. */
6600 if (aggregate_value_p (DECL_RESULT (subr), subr))
6602 /* Returning something that won't go in a register. */
6603 rtx value_address = 0;
6605 #ifdef PCC_STATIC_STRUCT_RETURN
6606 if (current_function_returns_pcc_struct)
6608 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6609 value_address = assemble_static_space (size);
6614 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 1);
6615 /* Expect to be passed the address of a place to store the value.
6616 If it is passed as an argument, assign_parms will take care of
6620 value_address = gen_reg_rtx (Pmode);
6621 emit_move_insn (value_address, sv);
6626 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6627 set_mem_attributes (x, DECL_RESULT (subr), 1);
6628 SET_DECL_RTL (DECL_RESULT (subr), x);
6631 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6632 /* If return mode is void, this decl rtl should not be used. */
6633 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6636 /* Compute the return values into a pseudo reg, which we will copy
6637 into the true return register after the cleanups are done. */
6639 /* In order to figure out what mode to use for the pseudo, we
6640 figure out what the mode of the eventual return register will
6641 actually be, and use that. */
6643 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6646 /* Structures that are returned in registers are not aggregate_value_p,
6647 so we may see a PARALLEL or a REG. */
6648 if (REG_P (hard_reg))
6649 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6650 else if (GET_CODE (hard_reg) == PARALLEL)
6651 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
6655 /* Set DECL_REGISTER flag so that expand_function_end will copy the
6656 result to the real return register(s). */
6657 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6660 /* Initialize rtx for parameters and local variables.
6661 In some cases this requires emitting insns. */
6663 assign_parms (subr);
6665 /* Copy the static chain now if it wasn't a register. The delay is to
6666 avoid conflicts with the parameter passing registers. */
6668 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6669 if (GET_CODE (static_chain_incoming_rtx) != REG)
6670 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6672 /* The following was moved from init_function_start.
6673 The move is supposed to make sdb output more accurate. */
6674 /* Indicate the beginning of the function body,
6675 as opposed to parm setup. */
6676 emit_note (NOTE_INSN_FUNCTION_BEG);
6678 if (GET_CODE (get_last_insn ()) != NOTE)
6679 emit_note (NOTE_INSN_DELETED);
6680 parm_birth_insn = get_last_insn ();
6682 context_display = 0;
6683 if (current_function_needs_context)
6685 /* Fetch static chain values for containing functions. */
6686 tem = decl_function_context (current_function_decl);
6687 /* Copy the static chain pointer into a pseudo. If we have
6688 small register classes, copy the value from memory if
6689 static_chain_incoming_rtx is a REG. */
6692 /* If the static chain originally came in a register, put it back
6693 there, then move it out in the next insn. The reason for
6694 this peculiar code is to satisfy function integration. */
6695 if (SMALL_REGISTER_CLASSES
6696 && GET_CODE (static_chain_incoming_rtx) == REG)
6697 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6698 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6703 tree rtlexp = make_node (RTL_EXPR);
6705 RTL_EXPR_RTL (rtlexp) = last_ptr;
6706 context_display = tree_cons (tem, rtlexp, context_display);
6707 tem = decl_function_context (tem);
6710 /* Chain thru stack frames, assuming pointer to next lexical frame
6711 is found at the place we always store it. */
6712 #ifdef FRAME_GROWS_DOWNWARD
6713 last_ptr = plus_constant (last_ptr,
6714 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6716 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6717 set_mem_alias_set (last_ptr, get_frame_alias_set ());
6718 last_ptr = copy_to_reg (last_ptr);
6720 /* If we are not optimizing, ensure that we know that this
6721 piece of context is live over the entire function. */
6723 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6728 if (current_function_instrument_entry_exit)
6730 rtx fun = DECL_RTL (current_function_decl);
6731 if (GET_CODE (fun) == MEM)
6732 fun = XEXP (fun, 0);
6735 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode,
6737 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6739 hard_frame_pointer_rtx),
6743 if (current_function_profile)
6746 PROFILE_HOOK (current_function_funcdef_no);
6750 /* After the display initializations is where the tail-recursion label
6751 should go, if we end up needing one. Ensure we have a NOTE here
6752 since some things (like trampolines) get placed before this. */
6753 tail_recursion_reentry = emit_note (NOTE_INSN_DELETED);
6755 /* Evaluate now the sizes of any types declared among the arguments. */
6756 expand_pending_sizes (nreverse (get_pending_sizes ()));
6758 /* Make sure there is a line number after the function entry setup code. */
6759 force_next_line_note ();
6762 /* Undo the effects of init_dummy_function_start. */
6764 expand_dummy_function_end (void)
6766 /* End any sequences that failed to be closed due to syntax errors. */
6767 while (in_sequence_p ())
6770 /* Outside function body, can't compute type's actual size
6771 until next function's body starts. */
6773 free_after_parsing (cfun);
6774 free_after_compilation (cfun);
6778 /* Call DOIT for each hard register used as a return value from
6779 the current function. */
6782 diddle_return_value (void (*doit) (rtx, void *), void *arg)
6784 rtx outgoing = current_function_return_rtx;
6789 if (GET_CODE (outgoing) == REG)
6790 (*doit) (outgoing, arg);
6791 else if (GET_CODE (outgoing) == PARALLEL)
6795 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6797 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6799 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6806 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6808 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6812 clobber_return_register (void)
6814 diddle_return_value (do_clobber_return_reg, NULL);
6816 /* In case we do use pseudo to return value, clobber it too. */
6817 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6819 tree decl_result = DECL_RESULT (current_function_decl);
6820 rtx decl_rtl = DECL_RTL (decl_result);
6821 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6823 do_clobber_return_reg (decl_rtl, NULL);
6829 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
6831 emit_insn (gen_rtx_USE (VOIDmode, reg));
6835 use_return_register (void)
6837 diddle_return_value (do_use_return_reg, NULL);
6840 static GTY(()) rtx initial_trampoline;
6842 /* Generate RTL for the end of the current function. */
6845 expand_function_end (void)
6850 finish_expr_for_function ();
6852 /* If arg_pointer_save_area was referenced only from a nested
6853 function, we will not have initialized it yet. Do that now. */
6854 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6855 get_arg_pointer_save_area (cfun);
6857 #ifdef NON_SAVING_SETJMP
6858 /* Don't put any variables in registers if we call setjmp
6859 on a machine that fails to restore the registers. */
6860 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6862 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6863 setjmp_protect (DECL_INITIAL (current_function_decl));
6865 setjmp_protect_args ();
6869 /* Initialize any trampolines required by this function. */
6870 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6872 tree function = TREE_PURPOSE (link);
6873 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6874 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6875 #ifdef TRAMPOLINE_TEMPLATE
6880 #ifdef TRAMPOLINE_TEMPLATE
6881 /* First make sure this compilation has a template for
6882 initializing trampolines. */
6883 if (initial_trampoline == 0)
6886 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6887 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
6891 /* Generate insns to initialize the trampoline. */
6893 tramp = round_trampoline_addr (XEXP (tramp, 0));
6894 #ifdef TRAMPOLINE_TEMPLATE
6895 blktramp = replace_equiv_address (initial_trampoline, tramp);
6896 emit_block_move (blktramp, initial_trampoline,
6897 GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL);
6899 trampolines_created = 1;
6900 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6904 /* Put those insns at entry to the containing function (this one). */
6905 emit_insn_before (seq, tail_recursion_reentry);
6908 /* If we are doing stack checking and this function makes calls,
6909 do a stack probe at the start of the function to ensure we have enough
6910 space for another stack frame. */
6911 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6915 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6916 if (GET_CODE (insn) == CALL_INSN)
6919 probe_stack_range (STACK_CHECK_PROTECT,
6920 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6923 emit_insn_before (seq, tail_recursion_reentry);
6928 /* Possibly warn about unused parameters. */
6929 if (warn_unused_parameter)
6933 for (decl = DECL_ARGUMENTS (current_function_decl);
6934 decl; decl = TREE_CHAIN (decl))
6935 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6936 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6937 warning ("%Junused parameter '%D'", decl, decl);
6940 /* Delete handlers for nonlocal gotos if nothing uses them. */
6941 if (nonlocal_goto_handler_slots != 0
6942 && ! current_function_has_nonlocal_label)
6945 /* End any sequences that failed to be closed due to syntax errors. */
6946 while (in_sequence_p ())
6949 /* Outside function body, can't compute type's actual size
6950 until next function's body starts. */
6951 immediate_size_expand--;
6953 clear_pending_stack_adjust ();
6954 do_pending_stack_adjust ();
6956 /* Mark the end of the function body.
6957 If control reaches this insn, the function can drop through
6958 without returning a value. */
6959 emit_note (NOTE_INSN_FUNCTION_END);
6961 /* Must mark the last line number note in the function, so that the test
6962 coverage code can avoid counting the last line twice. This just tells
6963 the code to ignore the immediately following line note, since there
6964 already exists a copy of this note somewhere above. This line number
6965 note is still needed for debugging though, so we can't delete it. */
6966 if (flag_test_coverage)
6967 emit_note (NOTE_INSN_REPEATED_LINE_NUMBER);
6969 /* Output a linenumber for the end of the function.
6970 SDB depends on this. */
6971 force_next_line_note ();
6972 emit_line_note (input_location);
6974 /* Before the return label (if any), clobber the return
6975 registers so that they are not propagated live to the rest of
6976 the function. This can only happen with functions that drop
6977 through; if there had been a return statement, there would
6978 have either been a return rtx, or a jump to the return label.
6980 We delay actual code generation after the current_function_value_rtx
6982 clobber_after = get_last_insn ();
6984 /* Output the label for the actual return from the function,
6985 if one is expected. This happens either because a function epilogue
6986 is used instead of a return instruction, or because a return was done
6987 with a goto in order to run local cleanups, or because of pcc-style
6988 structure returning. */
6990 emit_label (return_label);
6992 if (current_function_instrument_entry_exit)
6994 rtx fun = DECL_RTL (current_function_decl);
6995 if (GET_CODE (fun) == MEM)
6996 fun = XEXP (fun, 0);
6999 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode,
7001 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
7003 hard_frame_pointer_rtx),
7007 /* Let except.c know where it should emit the call to unregister
7008 the function context for sjlj exceptions. */
7009 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
7010 sjlj_emit_function_exit_after (get_last_insn ());
7012 /* If we had calls to alloca, and this machine needs
7013 an accurate stack pointer to exit the function,
7014 insert some code to save and restore the stack pointer. */
7015 #ifdef EXIT_IGNORE_STACK
7016 if (! EXIT_IGNORE_STACK)
7018 if (current_function_calls_alloca)
7022 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
7023 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
7026 /* If scalar return value was computed in a pseudo-reg, or was a named
7027 return value that got dumped to the stack, copy that to the hard
7029 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
7031 tree decl_result = DECL_RESULT (current_function_decl);
7032 rtx decl_rtl = DECL_RTL (decl_result);
7034 if (REG_P (decl_rtl)
7035 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
7036 : DECL_REGISTER (decl_result))
7038 rtx real_decl_rtl = current_function_return_rtx;
7040 /* This should be set in assign_parms. */
7041 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
7044 /* If this is a BLKmode structure being returned in registers,
7045 then use the mode computed in expand_return. Note that if
7046 decl_rtl is memory, then its mode may have been changed,
7047 but that current_function_return_rtx has not. */
7048 if (GET_MODE (real_decl_rtl) == BLKmode)
7049 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
7051 /* If a named return value dumped decl_return to memory, then
7052 we may need to re-do the PROMOTE_MODE signed/unsigned
7054 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
7056 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
7058 if (targetm.calls.promote_function_return (TREE_TYPE (current_function_decl)))
7059 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
7062 convert_move (real_decl_rtl, decl_rtl, unsignedp);
7064 else if (GET_CODE (real_decl_rtl) == PARALLEL)
7066 /* If expand_function_start has created a PARALLEL for decl_rtl,
7067 move the result to the real return registers. Otherwise, do
7068 a group load from decl_rtl for a named return. */
7069 if (GET_CODE (decl_rtl) == PARALLEL)
7070 emit_group_move (real_decl_rtl, decl_rtl);
7072 emit_group_load (real_decl_rtl, decl_rtl,
7073 TREE_TYPE (decl_result),
7074 int_size_in_bytes (TREE_TYPE (decl_result)));
7077 emit_move_insn (real_decl_rtl, decl_rtl);
7081 /* If returning a structure, arrange to return the address of the value
7082 in a place where debuggers expect to find it.
7084 If returning a structure PCC style,
7085 the caller also depends on this value.
7086 And current_function_returns_pcc_struct is not necessarily set. */
7087 if (current_function_returns_struct
7088 || current_function_returns_pcc_struct)
7091 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
7092 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
7093 #ifdef FUNCTION_OUTGOING_VALUE
7095 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
7096 current_function_decl);
7099 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
7102 /* Mark this as a function return value so integrate will delete the
7103 assignment and USE below when inlining this function. */
7104 REG_FUNCTION_VALUE_P (outgoing) = 1;
7106 /* The address may be ptr_mode and OUTGOING may be Pmode. */
7107 value_address = convert_memory_address (GET_MODE (outgoing),
7110 emit_move_insn (outgoing, value_address);
7112 /* Show return register used to hold result (in this case the address
7114 current_function_return_rtx = outgoing;
7117 /* If this is an implementation of throw, do what's necessary to
7118 communicate between __builtin_eh_return and the epilogue. */
7119 expand_eh_return ();
7121 /* Emit the actual code to clobber return register. */
7126 clobber_return_register ();
7130 after = emit_insn_after (seq, clobber_after);
7132 if (clobber_after != after)
7133 cfun->x_clobber_return_insn = after;
7136 /* Output the label for the naked return from the function, if one is
7137 expected. This is currently used only by __builtin_return. */
7138 if (naked_return_label)
7139 emit_label (naked_return_label);
7141 /* ??? This should no longer be necessary since stupid is no longer with
7142 us, but there are some parts of the compiler (eg reload_combine, and
7143 sh mach_dep_reorg) that still try and compute their own lifetime info
7144 instead of using the general framework. */
7145 use_return_register ();
7147 /* Fix up any gotos that jumped out to the outermost
7148 binding level of the function.
7149 Must follow emitting RETURN_LABEL. */
7151 /* If you have any cleanups to do at this point,
7152 and they need to create temporary variables,
7153 then you will lose. */
7154 expand_fixups (get_insns ());
7158 get_arg_pointer_save_area (struct function *f)
7160 rtx ret = f->x_arg_pointer_save_area;
7164 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
7165 f->x_arg_pointer_save_area = ret;
7168 if (f == cfun && ! f->arg_pointer_save_area_init)
7172 /* Save the arg pointer at the beginning of the function. The
7173 generated stack slot may not be a valid memory address, so we
7174 have to check it and fix it if necessary. */
7176 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
7180 push_topmost_sequence ();
7181 emit_insn_after (seq, get_insns ());
7182 pop_topmost_sequence ();
7188 /* Extend a vector that records the INSN_UIDs of INSNS
7189 (a list of one or more insns). */
7192 record_insns (rtx insns, varray_type *vecp)
7199 while (tmp != NULL_RTX)
7202 tmp = NEXT_INSN (tmp);
7205 i = VARRAY_SIZE (*vecp);
7206 VARRAY_GROW (*vecp, i + len);
7208 while (tmp != NULL_RTX)
7210 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
7212 tmp = NEXT_INSN (tmp);
7216 /* Set the specified locator to the insn chain. */
7218 set_insn_locators (rtx insn, int loc)
7220 while (insn != NULL_RTX)
7223 INSN_LOCATOR (insn) = loc;
7224 insn = NEXT_INSN (insn);
7228 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
7229 be running after reorg, SEQUENCE rtl is possible. */
7232 contains (rtx insn, varray_type vec)
7236 if (GET_CODE (insn) == INSN
7237 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7240 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7241 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7242 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7248 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7249 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7256 prologue_epilogue_contains (rtx insn)
7258 if (contains (insn, prologue))
7260 if (contains (insn, epilogue))
7266 sibcall_epilogue_contains (rtx insn)
7268 if (sibcall_epilogue)
7269 return contains (insn, sibcall_epilogue);
7274 /* Insert gen_return at the end of block BB. This also means updating
7275 block_for_insn appropriately. */
7278 emit_return_into_block (basic_block bb, rtx line_note)
7280 emit_jump_insn_after (gen_return (), bb->end);
7282 emit_note_copy_after (line_note, PREV_INSN (bb->end));
7284 #endif /* HAVE_return */
7286 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7288 /* These functions convert the epilogue into a variant that does not modify the
7289 stack pointer. This is used in cases where a function returns an object
7290 whose size is not known until it is computed. The called function leaves the
7291 object on the stack, leaves the stack depressed, and returns a pointer to
7294 What we need to do is track all modifications and references to the stack
7295 pointer, deleting the modifications and changing the references to point to
7296 the location the stack pointer would have pointed to had the modifications
7299 These functions need to be portable so we need to make as few assumptions
7300 about the epilogue as we can. However, the epilogue basically contains
7301 three things: instructions to reset the stack pointer, instructions to
7302 reload registers, possibly including the frame pointer, and an
7303 instruction to return to the caller.
7305 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7306 We also make no attempt to validate the insns we make since if they are
7307 invalid, we probably can't do anything valid. The intent is that these
7308 routines get "smarter" as more and more machines start to use them and
7309 they try operating on different epilogues.
7311 We use the following structure to track what the part of the epilogue that
7312 we've already processed has done. We keep two copies of the SP equivalence,
7313 one for use during the insn we are processing and one for use in the next
7314 insn. The difference is because one part of a PARALLEL may adjust SP
7315 and the other may use it. */
7319 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7320 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7321 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7322 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7323 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7324 should be set to once we no longer need
7326 rtx const_equiv[FIRST_PSEUDO_REGISTER]; /* Any known constant equivalences
7330 static void handle_epilogue_set (rtx, struct epi_info *);
7331 static void update_epilogue_consts (rtx, rtx, void *);
7332 static void emit_equiv_load (struct epi_info *);
7334 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
7335 no modifications to the stack pointer. Return the new list of insns. */
7338 keep_stack_depressed (rtx insns)
7341 struct epi_info info;
7344 /* If the epilogue is just a single instruction, it must be OK as is. */
7345 if (NEXT_INSN (insns) == NULL_RTX)
7348 /* Otherwise, start a sequence, initialize the information we have, and
7349 process all the insns we were given. */
7352 info.sp_equiv_reg = stack_pointer_rtx;
7354 info.equiv_reg_src = 0;
7356 for (j = 0; j < FIRST_PSEUDO_REGISTER; j++)
7357 info.const_equiv[j] = 0;
7361 while (insn != NULL_RTX)
7363 next = NEXT_INSN (insn);
7372 /* If this insn references the register that SP is equivalent to and
7373 we have a pending load to that register, we must force out the load
7374 first and then indicate we no longer know what SP's equivalent is. */
7375 if (info.equiv_reg_src != 0
7376 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7378 emit_equiv_load (&info);
7379 info.sp_equiv_reg = 0;
7382 info.new_sp_equiv_reg = info.sp_equiv_reg;
7383 info.new_sp_offset = info.sp_offset;
7385 /* If this is a (RETURN) and the return address is on the stack,
7386 update the address and change to an indirect jump. */
7387 if (GET_CODE (PATTERN (insn)) == RETURN
7388 || (GET_CODE (PATTERN (insn)) == PARALLEL
7389 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7391 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7393 HOST_WIDE_INT offset = 0;
7394 rtx jump_insn, jump_set;
7396 /* If the return address is in a register, we can emit the insn
7397 unchanged. Otherwise, it must be a MEM and we see what the
7398 base register and offset are. In any case, we have to emit any
7399 pending load to the equivalent reg of SP, if any. */
7400 if (GET_CODE (retaddr) == REG)
7402 emit_equiv_load (&info);
7407 else if (GET_CODE (retaddr) == MEM
7408 && GET_CODE (XEXP (retaddr, 0)) == REG)
7409 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7410 else if (GET_CODE (retaddr) == MEM
7411 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7412 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7413 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7415 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7416 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7421 /* If the base of the location containing the return pointer
7422 is SP, we must update it with the replacement address. Otherwise,
7423 just build the necessary MEM. */
7424 retaddr = plus_constant (base, offset);
7425 if (base == stack_pointer_rtx)
7426 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7427 plus_constant (info.sp_equiv_reg,
7430 retaddr = gen_rtx_MEM (Pmode, retaddr);
7432 /* If there is a pending load to the equivalent register for SP
7433 and we reference that register, we must load our address into
7434 a scratch register and then do that load. */
7435 if (info.equiv_reg_src
7436 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7441 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7442 if (HARD_REGNO_MODE_OK (regno, Pmode)
7443 && !fixed_regs[regno]
7444 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7445 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7447 && !refers_to_regno_p (regno,
7448 regno + HARD_REGNO_NREGS (regno,
7450 info.equiv_reg_src, NULL)
7451 && info.const_equiv[regno] == 0)
7454 if (regno == FIRST_PSEUDO_REGISTER)
7457 reg = gen_rtx_REG (Pmode, regno);
7458 emit_move_insn (reg, retaddr);
7462 emit_equiv_load (&info);
7463 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7465 /* Show the SET in the above insn is a RETURN. */
7466 jump_set = single_set (jump_insn);
7470 SET_IS_RETURN_P (jump_set) = 1;
7473 /* If SP is not mentioned in the pattern and its equivalent register, if
7474 any, is not modified, just emit it. Otherwise, if neither is set,
7475 replace the reference to SP and emit the insn. If none of those are
7476 true, handle each SET individually. */
7477 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7478 && (info.sp_equiv_reg == stack_pointer_rtx
7479 || !reg_set_p (info.sp_equiv_reg, insn)))
7481 else if (! reg_set_p (stack_pointer_rtx, insn)
7482 && (info.sp_equiv_reg == stack_pointer_rtx
7483 || !reg_set_p (info.sp_equiv_reg, insn)))
7485 if (! validate_replace_rtx (stack_pointer_rtx,
7486 plus_constant (info.sp_equiv_reg,
7493 else if (GET_CODE (PATTERN (insn)) == SET)
7494 handle_epilogue_set (PATTERN (insn), &info);
7495 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7497 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7498 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7499 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7504 info.sp_equiv_reg = info.new_sp_equiv_reg;
7505 info.sp_offset = info.new_sp_offset;
7507 /* Now update any constants this insn sets. */
7508 note_stores (PATTERN (insn), update_epilogue_consts, &info);
7512 insns = get_insns ();
7517 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7518 structure that contains information about what we've seen so far. We
7519 process this SET by either updating that data or by emitting one or
7523 handle_epilogue_set (rtx set, struct epi_info *p)
7525 /* First handle the case where we are setting SP. Record what it is being
7526 set from. If unknown, abort. */
7527 if (reg_set_p (stack_pointer_rtx, set))
7529 if (SET_DEST (set) != stack_pointer_rtx)
7532 if (GET_CODE (SET_SRC (set)) == PLUS)
7534 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7535 if (GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7536 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7537 else if (GET_CODE (XEXP (SET_SRC (set), 1)) == REG
7538 && REGNO (XEXP (SET_SRC (set), 1)) < FIRST_PSEUDO_REGISTER
7539 && p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))] != 0)
7541 = INTVAL (p->const_equiv[REGNO (XEXP (SET_SRC (set), 1))]);
7546 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7548 /* If we are adjusting SP, we adjust from the old data. */
7549 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7551 p->new_sp_equiv_reg = p->sp_equiv_reg;
7552 p->new_sp_offset += p->sp_offset;
7555 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7561 /* Next handle the case where we are setting SP's equivalent register.
7562 If we already have a value to set it to, abort. We could update, but
7563 there seems little point in handling that case. Note that we have
7564 to allow for the case where we are setting the register set in
7565 the previous part of a PARALLEL inside a single insn. But use the
7566 old offset for any updates within this insn. We must allow for the case
7567 where the register is being set in a different (usually wider) mode than
7569 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7571 if (p->equiv_reg_src != 0
7572 || GET_CODE (p->new_sp_equiv_reg) != REG
7573 || GET_CODE (SET_DEST (set)) != REG
7574 || GET_MODE_BITSIZE (GET_MODE (SET_DEST (set))) > BITS_PER_WORD
7575 || REGNO (p->new_sp_equiv_reg) != REGNO (SET_DEST (set)))
7579 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7580 plus_constant (p->sp_equiv_reg,
7584 /* Otherwise, replace any references to SP in the insn to its new value
7585 and emit the insn. */
7588 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7589 plus_constant (p->sp_equiv_reg,
7591 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7592 plus_constant (p->sp_equiv_reg,
7598 /* Update the tracking information for registers set to constants. */
7601 update_epilogue_consts (rtx dest, rtx x, void *data)
7603 struct epi_info *p = (struct epi_info *) data;
7605 if (GET_CODE (dest) != REG || REGNO (dest) >= FIRST_PSEUDO_REGISTER)
7607 else if (GET_CODE (x) == CLOBBER || ! rtx_equal_p (dest, SET_DEST (x))
7608 || GET_CODE (SET_SRC (x)) != CONST_INT)
7609 p->const_equiv[REGNO (dest)] = 0;
7611 p->const_equiv[REGNO (dest)] = SET_SRC (x);
7614 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7617 emit_equiv_load (struct epi_info *p)
7619 if (p->equiv_reg_src != 0)
7621 rtx dest = p->sp_equiv_reg;
7623 if (GET_MODE (p->equiv_reg_src) != GET_MODE (dest))
7624 dest = gen_rtx_REG (GET_MODE (p->equiv_reg_src),
7625 REGNO (p->sp_equiv_reg));
7627 emit_move_insn (dest, p->equiv_reg_src);
7628 p->equiv_reg_src = 0;
7633 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7634 this into place with notes indicating where the prologue ends and where
7635 the epilogue begins. Update the basic block information when possible. */
7638 thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED)
7642 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7645 #ifdef HAVE_prologue
7646 rtx prologue_end = NULL_RTX;
7648 #if defined (HAVE_epilogue) || defined(HAVE_return)
7649 rtx epilogue_end = NULL_RTX;
7652 #ifdef HAVE_prologue
7656 seq = gen_prologue ();
7659 /* Retain a map of the prologue insns. */
7660 record_insns (seq, &prologue);
7661 prologue_end = emit_note (NOTE_INSN_PROLOGUE_END);
7665 set_insn_locators (seq, prologue_locator);
7667 /* Can't deal with multiple successors of the entry block
7668 at the moment. Function should always have at least one
7670 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7673 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7678 /* If the exit block has no non-fake predecessors, we don't need
7680 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7681 if ((e->flags & EDGE_FAKE) == 0)
7687 if (optimize && HAVE_return)
7689 /* If we're allowed to generate a simple return instruction,
7690 then by definition we don't need a full epilogue. Examine
7691 the block that falls through to EXIT. If it does not
7692 contain any code, examine its predecessors and try to
7693 emit (conditional) return instructions. */
7699 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7700 if (e->flags & EDGE_FALLTHRU)
7706 /* Verify that there are no active instructions in the last block. */
7708 while (label && GET_CODE (label) != CODE_LABEL)
7710 if (active_insn_p (label))
7712 label = PREV_INSN (label);
7715 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7717 rtx epilogue_line_note = NULL_RTX;
7719 /* Locate the line number associated with the closing brace,
7720 if we can find one. */
7721 for (seq = get_last_insn ();
7722 seq && ! active_insn_p (seq);
7723 seq = PREV_INSN (seq))
7724 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7726 epilogue_line_note = seq;
7730 for (e = last->pred; e; e = e_next)
7732 basic_block bb = e->src;
7735 e_next = e->pred_next;
7736 if (bb == ENTRY_BLOCK_PTR)
7740 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7743 /* If we have an unconditional jump, we can replace that
7744 with a simple return instruction. */
7745 if (simplejump_p (jump))
7747 emit_return_into_block (bb, epilogue_line_note);
7751 /* If we have a conditional jump, we can try to replace
7752 that with a conditional return instruction. */
7753 else if (condjump_p (jump))
7755 if (! redirect_jump (jump, 0, 0))
7758 /* If this block has only one successor, it both jumps
7759 and falls through to the fallthru block, so we can't
7761 if (bb->succ->succ_next == NULL)
7767 /* Fix up the CFG for the successful change we just made. */
7768 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7771 /* Emit a return insn for the exit fallthru block. Whether
7772 this is still reachable will be determined later. */
7774 emit_barrier_after (last->end);
7775 emit_return_into_block (last, epilogue_line_note);
7776 epilogue_end = last->end;
7777 last->succ->flags &= ~EDGE_FALLTHRU;
7782 #ifdef HAVE_epilogue
7785 /* Find the edge that falls through to EXIT. Other edges may exist
7786 due to RETURN instructions, but those don't need epilogues.
7787 There really shouldn't be a mixture -- either all should have
7788 been converted or none, however... */
7790 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7791 if (e->flags & EDGE_FALLTHRU)
7797 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
7799 seq = gen_epilogue ();
7801 #ifdef INCOMING_RETURN_ADDR_RTX
7802 /* If this function returns with the stack depressed and we can support
7803 it, massage the epilogue to actually do that. */
7804 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7805 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7806 seq = keep_stack_depressed (seq);
7809 emit_jump_insn (seq);
7811 /* Retain a map of the epilogue insns. */
7812 record_insns (seq, &epilogue);
7813 set_insn_locators (seq, epilogue_locator);
7818 insert_insn_on_edge (seq, e);
7825 commit_edge_insertions ();
7827 #ifdef HAVE_sibcall_epilogue
7828 /* Emit sibling epilogues before any sibling call sites. */
7829 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7831 basic_block bb = e->src;
7836 if (GET_CODE (insn) != CALL_INSN
7837 || ! SIBLING_CALL_P (insn))
7841 emit_insn (gen_sibcall_epilogue ());
7845 /* Retain a map of the epilogue insns. Used in life analysis to
7846 avoid getting rid of sibcall epilogue insns. Do this before we
7847 actually emit the sequence. */
7848 record_insns (seq, &sibcall_epilogue);
7849 set_insn_locators (seq, epilogue_locator);
7851 i = PREV_INSN (insn);
7852 newinsn = emit_insn_before (seq, insn);
7856 #ifdef HAVE_prologue
7861 /* GDB handles `break f' by setting a breakpoint on the first
7862 line note after the prologue. Which means (1) that if
7863 there are line number notes before where we inserted the
7864 prologue we should move them, and (2) we should generate a
7865 note before the end of the first basic block, if there isn't
7868 ??? This behavior is completely broken when dealing with
7869 multiple entry functions. We simply place the note always
7870 into first basic block and let alternate entry points
7874 for (insn = prologue_end; insn; insn = prev)
7876 prev = PREV_INSN (insn);
7877 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7879 /* Note that we cannot reorder the first insn in the
7880 chain, since rest_of_compilation relies on that
7881 remaining constant. */
7884 reorder_insns (insn, insn, prologue_end);
7888 /* Find the last line number note in the first block. */
7889 for (insn = ENTRY_BLOCK_PTR->next_bb->end;
7890 insn != prologue_end && insn;
7891 insn = PREV_INSN (insn))
7892 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7895 /* If we didn't find one, make a copy of the first line number
7899 for (insn = next_active_insn (prologue_end);
7901 insn = PREV_INSN (insn))
7902 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7904 emit_note_copy_after (insn, prologue_end);
7910 #ifdef HAVE_epilogue
7915 /* Similarly, move any line notes that appear after the epilogue.
7916 There is no need, however, to be quite so anal about the existence
7918 for (insn = epilogue_end; insn; insn = next)
7920 next = NEXT_INSN (insn);
7921 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7922 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7928 /* Reposition the prologue-end and epilogue-begin notes after instruction
7929 scheduling and delayed branch scheduling. */
7932 reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED)
7934 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7935 rtx insn, last, note;
7938 if ((len = VARRAY_SIZE (prologue)) > 0)
7942 /* Scan from the beginning until we reach the last prologue insn.
7943 We apparently can't depend on basic_block_{head,end} after
7945 for (insn = f; insn; insn = NEXT_INSN (insn))
7947 if (GET_CODE (insn) == NOTE)
7949 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7952 else if (contains (insn, prologue))
7962 /* Find the prologue-end note if we haven't already, and
7963 move it to just after the last prologue insn. */
7966 for (note = last; (note = NEXT_INSN (note));)
7967 if (GET_CODE (note) == NOTE
7968 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7972 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7973 if (GET_CODE (last) == CODE_LABEL)
7974 last = NEXT_INSN (last);
7975 reorder_insns (note, note, last);
7979 if ((len = VARRAY_SIZE (epilogue)) > 0)
7983 /* Scan from the end until we reach the first epilogue insn.
7984 We apparently can't depend on basic_block_{head,end} after
7986 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
7988 if (GET_CODE (insn) == NOTE)
7990 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7993 else if (contains (insn, epilogue))
8003 /* Find the epilogue-begin note if we haven't already, and
8004 move it to just before the first epilogue insn. */
8007 for (note = insn; (note = PREV_INSN (note));)
8008 if (GET_CODE (note) == NOTE
8009 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
8013 if (PREV_INSN (last) != note)
8014 reorder_insns (note, note, PREV_INSN (last));
8017 #endif /* HAVE_prologue or HAVE_epilogue */
8020 /* Called once, at initialization, to initialize function.c. */
8023 init_function_once (void)
8025 VARRAY_INT_INIT (prologue, 0, "prologue");
8026 VARRAY_INT_INIT (epilogue, 0, "epilogue");
8027 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
8030 #include "gt-function.h"