1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002 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. */
51 #include "hard-reg-set.h"
52 #include "insn-config.h"
55 #include "basic-block.h"
61 #include "integrate.h"
62 #include "langhooks.h"
64 #ifndef TRAMPOLINE_ALIGNMENT
65 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
68 #ifndef LOCAL_ALIGNMENT
69 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
72 /* Some systems use __main in a way incompatible with its use in gcc, in these
73 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
74 give the same symbol without quotes for an alternative entry point. You
75 must define both, or neither. */
77 #define NAME__MAIN "__main"
78 #define SYMBOL__MAIN __main
81 /* Round a value to the lowest integer less than it that is a multiple of
82 the required alignment. Avoid using division in case the value is
83 negative. Assume the alignment is a power of two. */
84 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
86 /* Similar, but round to the next highest integer that meets the
88 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
90 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
91 during rtl generation. If they are different register numbers, this is
92 always true. It may also be true if
93 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
94 generation. See fix_lexical_addr for details. */
96 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
97 #define NEED_SEPARATE_AP
100 /* Nonzero if function being compiled doesn't contain any calls
101 (ignoring the prologue and epilogue). This is set prior to
102 local register allocation and is valid for the remaining
104 int current_function_is_leaf;
106 /* Nonzero if function being compiled doesn't contain any instructions
107 that can throw an exception. This is set prior to final. */
109 int current_function_nothrow;
111 /* Nonzero if function being compiled doesn't modify the stack pointer
112 (ignoring the prologue and epilogue). This is only valid after
113 life_analysis has run. */
114 int current_function_sp_is_unchanging;
116 /* Nonzero if the function being compiled is a leaf function which only
117 uses leaf registers. This is valid after reload (specifically after
118 sched2) and is useful only if the port defines LEAF_REGISTERS. */
119 int current_function_uses_only_leaf_regs;
121 /* Nonzero once virtual register instantiation has been done.
122 assign_stack_local uses frame_pointer_rtx when this is nonzero.
123 calls.c:emit_library_call_value_1 uses it to set up
124 post-instantiation libcalls. */
125 int virtuals_instantiated;
127 /* These variables hold pointers to functions to create and destroy
128 target specific, per-function data structures. */
129 void (*init_machine_status) PARAMS ((struct function *));
130 void (*free_machine_status) PARAMS ((struct function *));
131 /* This variable holds a pointer to a function to register any
132 data items in the target specific, per-function data structure
133 that will need garbage collection. */
134 void (*mark_machine_status) PARAMS ((struct function *));
136 /* Likewise, but for language-specific data. */
137 void (*init_lang_status) PARAMS ((struct function *));
138 void (*save_lang_status) PARAMS ((struct function *));
139 void (*restore_lang_status) PARAMS ((struct function *));
140 void (*mark_lang_status) PARAMS ((struct function *));
141 void (*free_lang_status) PARAMS ((struct function *));
143 /* The FUNCTION_DECL for an inline function currently being expanded. */
144 tree inline_function_decl;
146 /* The currently compiled function. */
147 struct function *cfun = 0;
149 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
150 static varray_type prologue;
151 static varray_type epilogue;
153 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
155 static varray_type sibcall_epilogue;
157 /* In order to evaluate some expressions, such as function calls returning
158 structures in memory, we need to temporarily allocate stack locations.
159 We record each allocated temporary in the following structure.
161 Associated with each temporary slot is a nesting level. When we pop up
162 one level, all temporaries associated with the previous level are freed.
163 Normally, all temporaries are freed after the execution of the statement
164 in which they were created. However, if we are inside a ({...}) grouping,
165 the result may be in a temporary and hence must be preserved. If the
166 result could be in a temporary, we preserve it if we can determine which
167 one it is in. If we cannot determine which temporary may contain the
168 result, all temporaries are preserved. A temporary is preserved by
169 pretending it was allocated at the previous nesting level.
171 Automatic variables are also assigned temporary slots, at the nesting
172 level where they are defined. They are marked a "kept" so that
173 free_temp_slots will not free them. */
177 /* Points to next temporary slot. */
178 struct temp_slot *next;
179 /* The rtx to used to reference the slot. */
181 /* The rtx used to represent the address if not the address of the
182 slot above. May be an EXPR_LIST if multiple addresses exist. */
184 /* The alignment (in bits) of the slot. */
186 /* The size, in units, of the slot. */
188 /* The type of the object in the slot, or zero if it doesn't correspond
189 to a type. We use this to determine whether a slot can be reused.
190 It can be reused if objects of the type of the new slot will always
191 conflict with objects of the type of the old slot. */
193 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
195 /* Non-zero if this temporary is currently in use. */
197 /* Non-zero if this temporary has its address taken. */
199 /* Nesting level at which this slot is being used. */
201 /* Non-zero if this should survive a call to free_temp_slots. */
203 /* The offset of the slot from the frame_pointer, including extra space
204 for alignment. This info is for combine_temp_slots. */
205 HOST_WIDE_INT base_offset;
206 /* The size of the slot, including extra space for alignment. This
207 info is for combine_temp_slots. */
208 HOST_WIDE_INT full_size;
211 /* This structure is used to record MEMs or pseudos used to replace VAR, any
212 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
213 maintain this list in case two operands of an insn were required to match;
214 in that case we must ensure we use the same replacement. */
216 struct fixup_replacement
220 struct fixup_replacement *next;
223 struct insns_for_mem_entry
225 /* The KEY in HE will be a MEM. */
226 struct hash_entry he;
227 /* These are the INSNS which reference the MEM. */
231 /* Forward declarations. */
233 static rtx assign_stack_local_1 PARAMS ((enum machine_mode, HOST_WIDE_INT,
234 int, struct function *));
235 static struct temp_slot *find_temp_slot_from_address PARAMS ((rtx));
236 static void put_reg_into_stack PARAMS ((struct function *, rtx, tree,
237 enum machine_mode, enum machine_mode,
238 int, unsigned int, int,
239 struct hash_table *));
240 static void schedule_fixup_var_refs PARAMS ((struct function *, rtx, tree,
242 struct hash_table *));
243 static void fixup_var_refs PARAMS ((rtx, enum machine_mode, int, rtx,
244 struct hash_table *));
245 static struct fixup_replacement
246 *find_fixup_replacement PARAMS ((struct fixup_replacement **, rtx));
247 static void fixup_var_refs_insns PARAMS ((rtx, rtx, enum machine_mode,
249 static void fixup_var_refs_insns_with_hash
250 PARAMS ((struct hash_table *, rtx,
251 enum machine_mode, int, rtx));
252 static void fixup_var_refs_insn PARAMS ((rtx, rtx, enum machine_mode,
254 static void fixup_var_refs_1 PARAMS ((rtx, enum machine_mode, rtx *, rtx,
255 struct fixup_replacement **, rtx));
256 static rtx fixup_memory_subreg PARAMS ((rtx, rtx, int));
257 static rtx walk_fixup_memory_subreg PARAMS ((rtx, rtx, int));
258 static rtx fixup_stack_1 PARAMS ((rtx, rtx));
259 static void optimize_bit_field PARAMS ((rtx, rtx, rtx *));
260 static void instantiate_decls PARAMS ((tree, int));
261 static void instantiate_decls_1 PARAMS ((tree, int));
262 static void instantiate_decl PARAMS ((rtx, HOST_WIDE_INT, int));
263 static rtx instantiate_new_reg PARAMS ((rtx, HOST_WIDE_INT *));
264 static int instantiate_virtual_regs_1 PARAMS ((rtx *, rtx, int));
265 static void delete_handlers PARAMS ((void));
266 static void pad_to_arg_alignment PARAMS ((struct args_size *, int,
267 struct args_size *));
268 #ifndef ARGS_GROW_DOWNWARD
269 static void pad_below PARAMS ((struct args_size *, enum machine_mode,
272 static rtx round_trampoline_addr PARAMS ((rtx));
273 static rtx adjust_trampoline_addr PARAMS ((rtx));
274 static tree *identify_blocks_1 PARAMS ((rtx, tree *, tree *, tree *));
275 static void reorder_blocks_0 PARAMS ((tree));
276 static void reorder_blocks_1 PARAMS ((rtx, tree, varray_type *));
277 static void reorder_fix_fragments PARAMS ((tree));
278 static tree blocks_nreverse PARAMS ((tree));
279 static int all_blocks PARAMS ((tree, tree *));
280 static tree *get_block_vector PARAMS ((tree, int *));
281 extern tree debug_find_var_in_block_tree PARAMS ((tree, tree));
282 /* We always define `record_insns' even if its not used so that we
283 can always export `prologue_epilogue_contains'. */
284 static void record_insns PARAMS ((rtx, varray_type *)) ATTRIBUTE_UNUSED;
285 static int contains PARAMS ((rtx, varray_type));
287 static void emit_return_into_block PARAMS ((basic_block, rtx));
289 static void put_addressof_into_stack PARAMS ((rtx, struct hash_table *));
290 static bool purge_addressof_1 PARAMS ((rtx *, rtx, int, int,
291 struct hash_table *));
292 static void purge_single_hard_subreg_set PARAMS ((rtx));
293 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
294 static rtx keep_stack_depressed PARAMS ((rtx));
296 static int is_addressof PARAMS ((rtx *, void *));
297 static struct hash_entry *insns_for_mem_newfunc PARAMS ((struct hash_entry *,
300 static unsigned long insns_for_mem_hash PARAMS ((hash_table_key));
301 static bool insns_for_mem_comp PARAMS ((hash_table_key, hash_table_key));
302 static int insns_for_mem_walk PARAMS ((rtx *, void *));
303 static void compute_insns_for_mem PARAMS ((rtx, rtx, struct hash_table *));
304 static void mark_function_status PARAMS ((struct function *));
305 static void maybe_mark_struct_function PARAMS ((void *));
306 static void prepare_function_start PARAMS ((void));
307 static void do_clobber_return_reg PARAMS ((rtx, void *));
308 static void do_use_return_reg PARAMS ((rtx, void *));
310 /* Pointer to chain of `struct function' for containing functions. */
311 static struct function *outer_function_chain;
313 /* Given a function decl for a containing function,
314 return the `struct function' for it. */
317 find_function_data (decl)
322 for (p = outer_function_chain; p; p = p->outer)
329 /* Save the current context for compilation of a nested function.
330 This is called from language-specific code. The caller should use
331 the save_lang_status callback to save any language-specific state,
332 since this function knows only about language-independent
336 push_function_context_to (context)
343 if (context == current_function_decl)
344 cfun->contains_functions = 1;
347 struct function *containing = find_function_data (context);
348 containing->contains_functions = 1;
353 init_dummy_function_start ();
356 p->outer = outer_function_chain;
357 outer_function_chain = p;
358 p->fixup_var_refs_queue = 0;
360 if (save_lang_status)
361 (*save_lang_status) (p);
367 push_function_context ()
369 push_function_context_to (current_function_decl);
372 /* Restore the last saved context, at the end of a nested function.
373 This function is called from language-specific code. */
376 pop_function_context_from (context)
377 tree context ATTRIBUTE_UNUSED;
379 struct function *p = outer_function_chain;
380 struct var_refs_queue *queue;
383 outer_function_chain = p->outer;
385 current_function_decl = p->decl;
388 restore_emit_status (p);
390 if (restore_lang_status)
391 (*restore_lang_status) (p);
393 /* Finish doing put_var_into_stack for any of our variables which became
394 addressable during the nested function. If only one entry has to be
395 fixed up, just do that one. Otherwise, first make a list of MEMs that
396 are not to be unshared. */
397 if (p->fixup_var_refs_queue == 0)
399 else if (p->fixup_var_refs_queue->next == 0)
400 fixup_var_refs (p->fixup_var_refs_queue->modified,
401 p->fixup_var_refs_queue->promoted_mode,
402 p->fixup_var_refs_queue->unsignedp,
403 p->fixup_var_refs_queue->modified, 0);
408 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
409 list = gen_rtx_EXPR_LIST (VOIDmode, queue->modified, list);
411 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
412 fixup_var_refs (queue->modified, queue->promoted_mode,
413 queue->unsignedp, list, 0);
417 p->fixup_var_refs_queue = 0;
419 /* Reset variables that have known state during rtx generation. */
420 rtx_equal_function_value_matters = 1;
421 virtuals_instantiated = 0;
422 generating_concat_p = 1;
426 pop_function_context ()
428 pop_function_context_from (current_function_decl);
431 /* Clear out all parts of the state in F that can safely be discarded
432 after the function has been parsed, but not compiled, to let
433 garbage collection reclaim the memory. */
436 free_after_parsing (f)
439 /* f->expr->forced_labels is used by code generation. */
440 /* f->emit->regno_reg_rtx is used by code generation. */
441 /* f->varasm is used by code generation. */
442 /* f->eh->eh_return_stub_label is used by code generation. */
444 if (free_lang_status)
445 (*free_lang_status) (f);
446 free_stmt_status (f);
449 /* Clear out all parts of the state in F that can safely be discarded
450 after the function has been compiled, to let garbage collection
451 reclaim the memory. */
454 free_after_compilation (f)
458 free_expr_status (f);
459 free_emit_status (f);
460 free_varasm_status (f);
462 if (free_machine_status)
463 (*free_machine_status) (f);
465 if (f->x_parm_reg_stack_loc)
466 free (f->x_parm_reg_stack_loc);
468 f->x_temp_slots = NULL;
469 f->arg_offset_rtx = NULL;
470 f->return_rtx = NULL;
471 f->internal_arg_pointer = NULL;
472 f->x_nonlocal_labels = NULL;
473 f->x_nonlocal_goto_handler_slots = NULL;
474 f->x_nonlocal_goto_handler_labels = NULL;
475 f->x_nonlocal_goto_stack_level = NULL;
476 f->x_cleanup_label = NULL;
477 f->x_return_label = NULL;
478 f->x_save_expr_regs = NULL;
479 f->x_stack_slot_list = NULL;
480 f->x_rtl_expr_chain = NULL;
481 f->x_tail_recursion_label = NULL;
482 f->x_tail_recursion_reentry = NULL;
483 f->x_arg_pointer_save_area = NULL;
484 f->x_clobber_return_insn = NULL;
485 f->x_context_display = NULL;
486 f->x_trampoline_list = NULL;
487 f->x_parm_birth_insn = NULL;
488 f->x_last_parm_insn = NULL;
489 f->x_parm_reg_stack_loc = NULL;
490 f->fixup_var_refs_queue = NULL;
491 f->original_arg_vector = NULL;
492 f->original_decl_initial = NULL;
493 f->inl_last_parm_insn = NULL;
494 f->epilogue_delay_list = NULL;
497 /* Allocate fixed slots in the stack frame of the current function. */
499 /* Return size needed for stack frame based on slots so far allocated in
501 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
502 the caller may have to do that. */
505 get_func_frame_size (f)
508 #ifdef FRAME_GROWS_DOWNWARD
509 return -f->x_frame_offset;
511 return f->x_frame_offset;
515 /* Return size needed for stack frame based on slots so far allocated.
516 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
517 the caller may have to do that. */
521 return get_func_frame_size (cfun);
524 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
525 with machine mode MODE.
527 ALIGN controls the amount of alignment for the address of the slot:
528 0 means according to MODE,
529 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
530 positive specifies alignment boundary in bits.
532 We do not round to stack_boundary here.
534 FUNCTION specifies the function to allocate in. */
537 assign_stack_local_1 (mode, size, align, function)
538 enum machine_mode mode;
541 struct function *function;
544 int bigend_correction = 0;
546 int frame_off, frame_alignment, frame_phase;
553 alignment = BIGGEST_ALIGNMENT;
555 alignment = GET_MODE_ALIGNMENT (mode);
557 /* Allow the target to (possibly) increase the alignment of this
559 type = (*lang_hooks.types.type_for_mode) (mode, 0);
561 alignment = LOCAL_ALIGNMENT (type, alignment);
563 alignment /= BITS_PER_UNIT;
565 else if (align == -1)
567 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
568 size = CEIL_ROUND (size, alignment);
571 alignment = align / BITS_PER_UNIT;
573 #ifdef FRAME_GROWS_DOWNWARD
574 function->x_frame_offset -= size;
577 /* Ignore alignment we can't do with expected alignment of the boundary. */
578 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
579 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
581 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
582 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
584 /* Calculate how many bytes the start of local variables is off from
586 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
587 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
588 frame_phase = frame_off ? frame_alignment - frame_off : 0;
590 /* Round frame offset to that alignment.
591 We must be careful here, since FRAME_OFFSET might be negative and
592 division with a negative dividend isn't as well defined as we might
593 like. So we instead assume that ALIGNMENT is a power of two and
594 use logical operations which are unambiguous. */
595 #ifdef FRAME_GROWS_DOWNWARD
596 function->x_frame_offset = FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment) + frame_phase;
598 function->x_frame_offset = CEIL_ROUND (function->x_frame_offset - frame_phase, alignment) + frame_phase;
601 /* On a big-endian machine, if we are allocating more space than we will use,
602 use the least significant bytes of those that are allocated. */
603 if (BYTES_BIG_ENDIAN && mode != BLKmode)
604 bigend_correction = size - GET_MODE_SIZE (mode);
606 /* If we have already instantiated virtual registers, return the actual
607 address relative to the frame pointer. */
608 if (function == cfun && virtuals_instantiated)
609 addr = plus_constant (frame_pointer_rtx,
610 (frame_offset + bigend_correction
611 + STARTING_FRAME_OFFSET));
613 addr = plus_constant (virtual_stack_vars_rtx,
614 function->x_frame_offset + bigend_correction);
616 #ifndef FRAME_GROWS_DOWNWARD
617 function->x_frame_offset += size;
620 x = gen_rtx_MEM (mode, addr);
622 function->x_stack_slot_list
623 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
628 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
632 assign_stack_local (mode, size, align)
633 enum machine_mode mode;
637 return assign_stack_local_1 (mode, size, align, cfun);
640 /* Allocate a temporary stack slot and record it for possible later
643 MODE is the machine mode to be given to the returned rtx.
645 SIZE is the size in units of the space required. We do no rounding here
646 since assign_stack_local will do any required rounding.
648 KEEP is 1 if this slot is to be retained after a call to
649 free_temp_slots. Automatic variables for a block are allocated
650 with this flag. KEEP is 2 if we allocate a longer term temporary,
651 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
652 if we are to allocate something at an inner level to be treated as
653 a variable in the block (e.g., a SAVE_EXPR).
655 TYPE is the type that will be used for the stack slot. */
658 assign_stack_temp_for_type (mode, size, keep, type)
659 enum machine_mode mode;
665 struct temp_slot *p, *best_p = 0;
667 /* If SIZE is -1 it means that somebody tried to allocate a temporary
668 of a variable size. */
673 align = BIGGEST_ALIGNMENT;
675 align = GET_MODE_ALIGNMENT (mode);
678 type = (*lang_hooks.types.type_for_mode) (mode, 0);
681 align = LOCAL_ALIGNMENT (type, align);
683 /* Try to find an available, already-allocated temporary of the proper
684 mode which meets the size and alignment requirements. Choose the
685 smallest one with the closest alignment. */
686 for (p = temp_slots; p; p = p->next)
687 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
689 && objects_must_conflict_p (p->type, type)
690 && (best_p == 0 || best_p->size > p->size
691 || (best_p->size == p->size && best_p->align > p->align)))
693 if (p->align == align && p->size == size)
701 /* Make our best, if any, the one to use. */
704 /* If there are enough aligned bytes left over, make them into a new
705 temp_slot so that the extra bytes don't get wasted. Do this only
706 for BLKmode slots, so that we can be sure of the alignment. */
707 if (GET_MODE (best_p->slot) == BLKmode)
709 int alignment = best_p->align / BITS_PER_UNIT;
710 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
712 if (best_p->size - rounded_size >= alignment)
714 p = (struct temp_slot *) ggc_alloc (sizeof (struct temp_slot));
715 p->in_use = p->addr_taken = 0;
716 p->size = best_p->size - rounded_size;
717 p->base_offset = best_p->base_offset + rounded_size;
718 p->full_size = best_p->full_size - rounded_size;
719 p->slot = gen_rtx_MEM (BLKmode,
720 plus_constant (XEXP (best_p->slot, 0),
722 p->align = best_p->align;
725 p->type = best_p->type;
726 p->next = temp_slots;
729 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
732 best_p->size = rounded_size;
733 best_p->full_size = rounded_size;
740 /* If we still didn't find one, make a new temporary. */
743 HOST_WIDE_INT frame_offset_old = frame_offset;
745 p = (struct temp_slot *) ggc_alloc (sizeof (struct temp_slot));
747 /* We are passing an explicit alignment request to assign_stack_local.
748 One side effect of that is assign_stack_local will not round SIZE
749 to ensure the frame offset remains suitably aligned.
751 So for requests which depended on the rounding of SIZE, we go ahead
752 and round it now. We also make sure ALIGNMENT is at least
753 BIGGEST_ALIGNMENT. */
754 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
756 p->slot = assign_stack_local (mode,
758 ? CEIL_ROUND (size, align / BITS_PER_UNIT)
764 /* The following slot size computation is necessary because we don't
765 know the actual size of the temporary slot until assign_stack_local
766 has performed all the frame alignment and size rounding for the
767 requested temporary. Note that extra space added for alignment
768 can be either above or below this stack slot depending on which
769 way the frame grows. We include the extra space if and only if it
770 is above this slot. */
771 #ifdef FRAME_GROWS_DOWNWARD
772 p->size = frame_offset_old - frame_offset;
777 /* Now define the fields used by combine_temp_slots. */
778 #ifdef FRAME_GROWS_DOWNWARD
779 p->base_offset = frame_offset;
780 p->full_size = frame_offset_old - frame_offset;
782 p->base_offset = frame_offset_old;
783 p->full_size = frame_offset - frame_offset_old;
786 p->next = temp_slots;
792 p->rtl_expr = seq_rtl_expr;
797 p->level = target_temp_slot_level;
802 p->level = var_temp_slot_level;
807 p->level = temp_slot_level;
811 /* We may be reusing an old slot, so clear any MEM flags that may have been
813 RTX_UNCHANGING_P (p->slot) = 0;
814 MEM_IN_STRUCT_P (p->slot) = 0;
815 MEM_SCALAR_P (p->slot) = 0;
816 MEM_VOLATILE_P (p->slot) = 0;
817 set_mem_alias_set (p->slot, 0);
819 /* If we know the alias set for the memory that will be used, use
820 it. If there's no TYPE, then we don't know anything about the
821 alias set for the memory. */
822 set_mem_alias_set (p->slot, type ? get_alias_set (type) : 0);
823 set_mem_align (p->slot, align);
825 /* If a type is specified, set the relevant flags. */
828 RTX_UNCHANGING_P (p->slot) = TYPE_READONLY (type);
829 MEM_VOLATILE_P (p->slot) = TYPE_VOLATILE (type);
830 MEM_SET_IN_STRUCT_P (p->slot, AGGREGATE_TYPE_P (type));
836 /* Allocate a temporary stack slot and record it for possible later
837 reuse. First three arguments are same as in preceding function. */
840 assign_stack_temp (mode, size, keep)
841 enum machine_mode mode;
845 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
848 /* Assign a temporary.
849 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
850 and so that should be used in error messages. In either case, we
851 allocate of the given type.
852 KEEP is as for assign_stack_temp.
853 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
854 it is 0 if a register is OK.
855 DONT_PROMOTE is 1 if we should not promote values in register
859 assign_temp (type_or_decl, keep, memory_required, dont_promote)
863 int dont_promote ATTRIBUTE_UNUSED;
866 enum machine_mode mode;
867 #ifndef PROMOTE_FOR_CALL_ONLY
871 if (DECL_P (type_or_decl))
872 decl = type_or_decl, type = TREE_TYPE (decl);
874 decl = NULL, type = type_or_decl;
876 mode = TYPE_MODE (type);
877 #ifndef PROMOTE_FOR_CALL_ONLY
878 unsignedp = TREE_UNSIGNED (type);
881 if (mode == BLKmode || memory_required)
883 HOST_WIDE_INT size = int_size_in_bytes (type);
886 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
887 problems with allocating the stack space. */
891 /* Unfortunately, we don't yet know how to allocate variable-sized
892 temporaries. However, sometimes we have a fixed upper limit on
893 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
894 instead. This is the case for Chill variable-sized strings. */
895 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
896 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
897 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
898 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
900 /* The size of the temporary may be too large to fit into an integer. */
901 /* ??? Not sure this should happen except for user silliness, so limit
902 this to things that aren't compiler-generated temporaries. The
903 rest of the time we'll abort in assign_stack_temp_for_type. */
904 if (decl && size == -1
905 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
907 error_with_decl (decl, "size of variable `%s' is too large");
911 tmp = assign_stack_temp_for_type (mode, size, keep, type);
915 #ifndef PROMOTE_FOR_CALL_ONLY
917 mode = promote_mode (type, mode, &unsignedp, 0);
920 return gen_reg_rtx (mode);
923 /* Combine temporary stack slots which are adjacent on the stack.
925 This allows for better use of already allocated stack space. This is only
926 done for BLKmode slots because we can be sure that we won't have alignment
927 problems in this case. */
930 combine_temp_slots ()
932 struct temp_slot *p, *q;
933 struct temp_slot *prev_p, *prev_q;
936 /* We can't combine slots, because the information about which slot
937 is in which alias set will be lost. */
938 if (flag_strict_aliasing)
941 /* If there are a lot of temp slots, don't do anything unless
942 high levels of optimization. */
943 if (! flag_expensive_optimizations)
944 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
945 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
948 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
952 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
953 for (q = p->next, prev_q = p; q; q = prev_q->next)
956 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
958 if (p->base_offset + p->full_size == q->base_offset)
960 /* Q comes after P; combine Q into P. */
962 p->full_size += q->full_size;
965 else if (q->base_offset + q->full_size == p->base_offset)
967 /* P comes after Q; combine P into Q. */
969 q->full_size += p->full_size;
974 /* Either delete Q or advance past it. */
976 prev_q->next = q->next;
980 /* Either delete P or advance past it. */
984 prev_p->next = p->next;
986 temp_slots = p->next;
993 /* Find the temp slot corresponding to the object at address X. */
995 static struct temp_slot *
996 find_temp_slot_from_address (x)
1002 for (p = temp_slots; p; p = p->next)
1007 else if (XEXP (p->slot, 0) == x
1009 || (GET_CODE (x) == PLUS
1010 && XEXP (x, 0) == virtual_stack_vars_rtx
1011 && GET_CODE (XEXP (x, 1)) == CONST_INT
1012 && INTVAL (XEXP (x, 1)) >= p->base_offset
1013 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size))
1016 else if (p->address != 0 && GET_CODE (p->address) == EXPR_LIST)
1017 for (next = p->address; next; next = XEXP (next, 1))
1018 if (XEXP (next, 0) == x)
1022 /* If we have a sum involving a register, see if it points to a temp
1024 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
1025 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
1027 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
1028 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1034 /* Indicate that NEW is an alternate way of referring to the temp slot
1035 that previously was known by OLD. */
1038 update_temp_slot_address (old, new)
1041 struct temp_slot *p;
1043 if (rtx_equal_p (old, new))
1046 p = find_temp_slot_from_address (old);
1048 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1049 is a register, see if one operand of the PLUS is a temporary
1050 location. If so, NEW points into it. Otherwise, if both OLD and
1051 NEW are a PLUS and if there is a register in common between them.
1052 If so, try a recursive call on those values. */
1055 if (GET_CODE (old) != PLUS)
1058 if (GET_CODE (new) == REG)
1060 update_temp_slot_address (XEXP (old, 0), new);
1061 update_temp_slot_address (XEXP (old, 1), new);
1064 else if (GET_CODE (new) != PLUS)
1067 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1068 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1069 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1070 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1071 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1072 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1073 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1074 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1079 /* Otherwise add an alias for the temp's address. */
1080 else if (p->address == 0)
1084 if (GET_CODE (p->address) != EXPR_LIST)
1085 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1087 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1091 /* If X could be a reference to a temporary slot, mark the fact that its
1092 address was taken. */
1095 mark_temp_addr_taken (x)
1098 struct temp_slot *p;
1103 /* If X is not in memory or is at a constant address, it cannot be in
1104 a temporary slot. */
1105 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1108 p = find_temp_slot_from_address (XEXP (x, 0));
1113 /* If X could be a reference to a temporary slot, mark that slot as
1114 belonging to the to one level higher than the current level. If X
1115 matched one of our slots, just mark that one. Otherwise, we can't
1116 easily predict which it is, so upgrade all of them. Kept slots
1117 need not be touched.
1119 This is called when an ({...}) construct occurs and a statement
1120 returns a value in memory. */
1123 preserve_temp_slots (x)
1126 struct temp_slot *p = 0;
1128 /* If there is no result, we still might have some objects whose address
1129 were taken, so we need to make sure they stay around. */
1132 for (p = temp_slots; p; p = p->next)
1133 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1139 /* If X is a register that is being used as a pointer, see if we have
1140 a temporary slot we know it points to. To be consistent with
1141 the code below, we really should preserve all non-kept slots
1142 if we can't find a match, but that seems to be much too costly. */
1143 if (GET_CODE (x) == REG && REG_POINTER (x))
1144 p = find_temp_slot_from_address (x);
1146 /* If X is not in memory or is at a constant address, it cannot be in
1147 a temporary slot, but it can contain something whose address was
1149 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1151 for (p = temp_slots; p; p = p->next)
1152 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1158 /* First see if we can find a match. */
1160 p = find_temp_slot_from_address (XEXP (x, 0));
1164 /* Move everything at our level whose address was taken to our new
1165 level in case we used its address. */
1166 struct temp_slot *q;
1168 if (p->level == temp_slot_level)
1170 for (q = temp_slots; q; q = q->next)
1171 if (q != p && q->addr_taken && q->level == p->level)
1180 /* Otherwise, preserve all non-kept slots at this level. */
1181 for (p = temp_slots; p; p = p->next)
1182 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1186 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1187 with that RTL_EXPR, promote it into a temporary slot at the present
1188 level so it will not be freed when we free slots made in the
1192 preserve_rtl_expr_result (x)
1195 struct temp_slot *p;
1197 /* If X is not in memory or is at a constant address, it cannot be in
1198 a temporary slot. */
1199 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1202 /* If we can find a match, move it to our level unless it is already at
1204 p = find_temp_slot_from_address (XEXP (x, 0));
1207 p->level = MIN (p->level, temp_slot_level);
1214 /* Free all temporaries used so far. This is normally called at the end
1215 of generating code for a statement. Don't free any temporaries
1216 currently in use for an RTL_EXPR that hasn't yet been emitted.
1217 We could eventually do better than this since it can be reused while
1218 generating the same RTL_EXPR, but this is complex and probably not
1224 struct temp_slot *p;
1226 for (p = temp_slots; p; p = p->next)
1227 if (p->in_use && p->level == temp_slot_level && ! p->keep
1228 && p->rtl_expr == 0)
1231 combine_temp_slots ();
1234 /* Free all temporary slots used in T, an RTL_EXPR node. */
1237 free_temps_for_rtl_expr (t)
1240 struct temp_slot *p;
1242 for (p = temp_slots; p; p = p->next)
1243 if (p->rtl_expr == t)
1245 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1246 needs to be preserved. This can happen if a temporary in
1247 the RTL_EXPR was addressed; preserve_temp_slots will move
1248 the temporary into a higher level. */
1249 if (temp_slot_level <= p->level)
1252 p->rtl_expr = NULL_TREE;
1255 combine_temp_slots ();
1258 /* Mark all temporaries ever allocated in this function as not suitable
1259 for reuse until the current level is exited. */
1262 mark_all_temps_used ()
1264 struct temp_slot *p;
1266 for (p = temp_slots; p; p = p->next)
1268 p->in_use = p->keep = 1;
1269 p->level = MIN (p->level, temp_slot_level);
1273 /* Push deeper into the nesting level for stack temporaries. */
1281 /* Likewise, but save the new level as the place to allocate variables
1286 push_temp_slots_for_block ()
1290 var_temp_slot_level = temp_slot_level;
1293 /* Likewise, but save the new level as the place to allocate temporaries
1294 for TARGET_EXPRs. */
1297 push_temp_slots_for_target ()
1301 target_temp_slot_level = temp_slot_level;
1304 /* Set and get the value of target_temp_slot_level. The only
1305 permitted use of these functions is to save and restore this value. */
1308 get_target_temp_slot_level ()
1310 return target_temp_slot_level;
1314 set_target_temp_slot_level (level)
1317 target_temp_slot_level = level;
1321 /* Pop a temporary nesting level. All slots in use in the current level
1327 struct temp_slot *p;
1329 for (p = temp_slots; p; p = p->next)
1330 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1333 combine_temp_slots ();
1338 /* Initialize temporary slots. */
1343 /* We have not allocated any temporaries yet. */
1345 temp_slot_level = 0;
1346 var_temp_slot_level = 0;
1347 target_temp_slot_level = 0;
1350 /* Retroactively move an auto variable from a register to a stack slot.
1351 This is done when an address-reference to the variable is seen. */
1354 put_var_into_stack (decl)
1358 enum machine_mode promoted_mode, decl_mode;
1359 struct function *function = 0;
1361 int can_use_addressof;
1362 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1363 int usedp = (TREE_USED (decl)
1364 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1366 context = decl_function_context (decl);
1368 /* Get the current rtl used for this object and its original mode. */
1369 reg = (TREE_CODE (decl) == SAVE_EXPR
1370 ? SAVE_EXPR_RTL (decl)
1371 : DECL_RTL_IF_SET (decl));
1373 /* No need to do anything if decl has no rtx yet
1374 since in that case caller is setting TREE_ADDRESSABLE
1375 and a stack slot will be assigned when the rtl is made. */
1379 /* Get the declared mode for this object. */
1380 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1381 : DECL_MODE (decl));
1382 /* Get the mode it's actually stored in. */
1383 promoted_mode = GET_MODE (reg);
1385 /* If this variable comes from an outer function, find that
1386 function's saved context. Don't use find_function_data here,
1387 because it might not be in any active function.
1388 FIXME: Is that really supposed to happen?
1389 It does in ObjC at least. */
1390 if (context != current_function_decl && context != inline_function_decl)
1391 for (function = outer_function_chain; function; function = function->outer)
1392 if (function->decl == context)
1395 /* If this is a variable-size object with a pseudo to address it,
1396 put that pseudo into the stack, if the var is nonlocal. */
1397 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1398 && GET_CODE (reg) == MEM
1399 && GET_CODE (XEXP (reg, 0)) == REG
1400 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1402 reg = XEXP (reg, 0);
1403 decl_mode = promoted_mode = GET_MODE (reg);
1409 /* FIXME make it work for promoted modes too */
1410 && decl_mode == promoted_mode
1411 #ifdef NON_SAVING_SETJMP
1412 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1416 /* If we can't use ADDRESSOF, make sure we see through one we already
1418 if (! can_use_addressof && GET_CODE (reg) == MEM
1419 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1420 reg = XEXP (XEXP (reg, 0), 0);
1422 /* Now we should have a value that resides in one or more pseudo regs. */
1424 if (GET_CODE (reg) == REG)
1426 /* If this variable lives in the current function and we don't need
1427 to put things in the stack for the sake of setjmp, try to keep it
1428 in a register until we know we actually need the address. */
1429 if (can_use_addressof)
1430 gen_mem_addressof (reg, decl);
1432 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1433 decl_mode, volatilep, 0, usedp, 0);
1435 else if (GET_CODE (reg) == CONCAT)
1437 /* A CONCAT contains two pseudos; put them both in the stack.
1438 We do it so they end up consecutive.
1439 We fixup references to the parts only after we fixup references
1440 to the whole CONCAT, lest we do double fixups for the latter
1442 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1443 tree part_type = (*lang_hooks.types.type_for_mode) (part_mode, 0);
1444 rtx lopart = XEXP (reg, 0);
1445 rtx hipart = XEXP (reg, 1);
1446 #ifdef FRAME_GROWS_DOWNWARD
1447 /* Since part 0 should have a lower address, do it second. */
1448 put_reg_into_stack (function, hipart, part_type, part_mode,
1449 part_mode, volatilep, 0, 0, 0);
1450 put_reg_into_stack (function, lopart, part_type, part_mode,
1451 part_mode, volatilep, 0, 0, 0);
1453 put_reg_into_stack (function, lopart, part_type, part_mode,
1454 part_mode, volatilep, 0, 0, 0);
1455 put_reg_into_stack (function, hipart, part_type, part_mode,
1456 part_mode, volatilep, 0, 0, 0);
1459 /* Change the CONCAT into a combined MEM for both parts. */
1460 PUT_CODE (reg, MEM);
1461 MEM_ATTRS (reg) = 0;
1463 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1464 already computed alias sets. Here we want to re-generate. */
1466 SET_DECL_RTL (decl, NULL);
1467 set_mem_attributes (reg, decl, 1);
1469 SET_DECL_RTL (decl, reg);
1471 /* The two parts are in memory order already.
1472 Use the lower parts address as ours. */
1473 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1474 /* Prevent sharing of rtl that might lose. */
1475 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1476 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1479 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1481 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1482 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1489 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1490 into the stack frame of FUNCTION (0 means the current function).
1491 DECL_MODE is the machine mode of the user-level data type.
1492 PROMOTED_MODE is the machine mode of the register.
1493 VOLATILE_P is nonzero if this is for a "volatile" decl.
1494 USED_P is nonzero if this reg might have already been used in an insn. */
1497 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1498 original_regno, used_p, ht)
1499 struct function *function;
1502 enum machine_mode promoted_mode, decl_mode;
1504 unsigned int original_regno;
1506 struct hash_table *ht;
1508 struct function *func = function ? function : cfun;
1510 unsigned int regno = original_regno;
1513 regno = REGNO (reg);
1515 if (regno < func->x_max_parm_reg)
1516 new = func->x_parm_reg_stack_loc[regno];
1519 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1521 PUT_CODE (reg, MEM);
1522 PUT_MODE (reg, decl_mode);
1523 XEXP (reg, 0) = XEXP (new, 0);
1524 MEM_ATTRS (reg) = 0;
1525 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1526 MEM_VOLATILE_P (reg) = volatile_p;
1528 /* If this is a memory ref that contains aggregate components,
1529 mark it as such for cse and loop optimize. If we are reusing a
1530 previously generated stack slot, then we need to copy the bit in
1531 case it was set for other reasons. For instance, it is set for
1532 __builtin_va_alist. */
1535 MEM_SET_IN_STRUCT_P (reg,
1536 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1537 set_mem_alias_set (reg, get_alias_set (type));
1541 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1544 /* Make sure that all refs to the variable, previously made
1545 when it was a register, are fixed up to be valid again.
1546 See function above for meaning of arguments. */
1549 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht)
1550 struct function *function;
1553 enum machine_mode promoted_mode;
1554 struct hash_table *ht;
1556 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1560 struct var_refs_queue *temp;
1563 = (struct var_refs_queue *) ggc_alloc (sizeof (struct var_refs_queue));
1564 temp->modified = reg;
1565 temp->promoted_mode = promoted_mode;
1566 temp->unsignedp = unsigned_p;
1567 temp->next = function->fixup_var_refs_queue;
1568 function->fixup_var_refs_queue = temp;
1571 /* Variable is local; fix it up now. */
1572 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht);
1576 fixup_var_refs (var, promoted_mode, unsignedp, may_share, ht)
1578 enum machine_mode promoted_mode;
1580 struct hash_table *ht;
1584 rtx first_insn = get_insns ();
1585 struct sequence_stack *stack = seq_stack;
1586 tree rtl_exps = rtl_expr_chain;
1588 /* If there's a hash table, it must record all uses of VAR. */
1593 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp,
1598 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1599 stack == 0, may_share);
1601 /* Scan all pending sequences too. */
1602 for (; stack; stack = stack->next)
1604 push_to_full_sequence (stack->first, stack->last);
1605 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1606 stack->next != 0, may_share);
1607 /* Update remembered end of sequence
1608 in case we added an insn at the end. */
1609 stack->last = get_last_insn ();
1613 /* Scan all waiting RTL_EXPRs too. */
1614 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1616 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1617 if (seq != const0_rtx && seq != 0)
1619 push_to_sequence (seq);
1620 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1627 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1628 some part of an insn. Return a struct fixup_replacement whose OLD
1629 value is equal to X. Allocate a new structure if no such entry exists. */
1631 static struct fixup_replacement *
1632 find_fixup_replacement (replacements, x)
1633 struct fixup_replacement **replacements;
1636 struct fixup_replacement *p;
1638 /* See if we have already replaced this. */
1639 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1644 p = (struct fixup_replacement *) xmalloc (sizeof (struct fixup_replacement));
1647 p->next = *replacements;
1654 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1655 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1656 for the current function. MAY_SHARE is either a MEM that is not
1657 to be unshared or a list of them. */
1660 fixup_var_refs_insns (insn, var, promoted_mode, unsignedp, toplevel, may_share)
1663 enum machine_mode promoted_mode;
1670 /* fixup_var_refs_insn might modify insn, so save its next
1672 rtx next = NEXT_INSN (insn);
1674 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1675 the three sequences they (potentially) contain, and process
1676 them recursively. The CALL_INSN itself is not interesting. */
1678 if (GET_CODE (insn) == CALL_INSN
1679 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1683 /* Look at the Normal call, sibling call and tail recursion
1684 sequences attached to the CALL_PLACEHOLDER. */
1685 for (i = 0; i < 3; i++)
1687 rtx seq = XEXP (PATTERN (insn), i);
1690 push_to_sequence (seq);
1691 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1693 XEXP (PATTERN (insn), i) = get_insns ();
1699 else if (INSN_P (insn))
1700 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel,
1707 /* Look up the insns which reference VAR in HT and fix them up. Other
1708 arguments are the same as fixup_var_refs_insns.
1710 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1711 because the hash table will point straight to the interesting insn
1712 (inside the CALL_PLACEHOLDER). */
1715 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp, may_share)
1716 struct hash_table *ht;
1718 enum machine_mode promoted_mode;
1722 struct insns_for_mem_entry *ime
1723 = (struct insns_for_mem_entry *) hash_lookup (ht, var,
1724 /*create=*/0, /*copy=*/0);
1727 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1))
1728 if (INSN_P (XEXP (insn_list, 0)))
1729 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode,
1730 unsignedp, 1, may_share);
1734 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1735 the insn under examination, VAR is the variable to fix up
1736 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1737 TOPLEVEL is nonzero if this is the main insn chain for this
1741 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel, no_share)
1744 enum machine_mode promoted_mode;
1750 rtx set, prev, prev_set;
1753 /* Remember the notes in case we delete the insn. */
1754 note = REG_NOTES (insn);
1756 /* If this is a CLOBBER of VAR, delete it.
1758 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1759 and REG_RETVAL notes too. */
1760 if (GET_CODE (PATTERN (insn)) == CLOBBER
1761 && (XEXP (PATTERN (insn), 0) == var
1762 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1763 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1764 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1766 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1767 /* The REG_LIBCALL note will go away since we are going to
1768 turn INSN into a NOTE, so just delete the
1769 corresponding REG_RETVAL note. */
1770 remove_note (XEXP (note, 0),
1771 find_reg_note (XEXP (note, 0), REG_RETVAL,
1777 /* The insn to load VAR from a home in the arglist
1778 is now a no-op. When we see it, just delete it.
1779 Similarly if this is storing VAR from a register from which
1780 it was loaded in the previous insn. This will occur
1781 when an ADDRESSOF was made for an arglist slot. */
1783 && (set = single_set (insn)) != 0
1784 && SET_DEST (set) == var
1785 /* If this represents the result of an insn group,
1786 don't delete the insn. */
1787 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1788 && (rtx_equal_p (SET_SRC (set), var)
1789 || (GET_CODE (SET_SRC (set)) == REG
1790 && (prev = prev_nonnote_insn (insn)) != 0
1791 && (prev_set = single_set (prev)) != 0
1792 && SET_DEST (prev_set) == SET_SRC (set)
1793 && rtx_equal_p (SET_SRC (prev_set), var))))
1799 struct fixup_replacement *replacements = 0;
1800 rtx next_insn = NEXT_INSN (insn);
1802 if (SMALL_REGISTER_CLASSES)
1804 /* If the insn that copies the results of a CALL_INSN
1805 into a pseudo now references VAR, we have to use an
1806 intermediate pseudo since we want the life of the
1807 return value register to be only a single insn.
1809 If we don't use an intermediate pseudo, such things as
1810 address computations to make the address of VAR valid
1811 if it is not can be placed between the CALL_INSN and INSN.
1813 To make sure this doesn't happen, we record the destination
1814 of the CALL_INSN and see if the next insn uses both that
1817 if (call_dest != 0 && GET_CODE (insn) == INSN
1818 && reg_mentioned_p (var, PATTERN (insn))
1819 && reg_mentioned_p (call_dest, PATTERN (insn)))
1821 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1823 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1825 PATTERN (insn) = replace_rtx (PATTERN (insn),
1829 if (GET_CODE (insn) == CALL_INSN
1830 && GET_CODE (PATTERN (insn)) == SET)
1831 call_dest = SET_DEST (PATTERN (insn));
1832 else if (GET_CODE (insn) == CALL_INSN
1833 && GET_CODE (PATTERN (insn)) == PARALLEL
1834 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1835 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1840 /* See if we have to do anything to INSN now that VAR is in
1841 memory. If it needs to be loaded into a pseudo, use a single
1842 pseudo for the entire insn in case there is a MATCH_DUP
1843 between two operands. We pass a pointer to the head of
1844 a list of struct fixup_replacements. If fixup_var_refs_1
1845 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1846 it will record them in this list.
1848 If it allocated a pseudo for any replacement, we copy into
1851 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1852 &replacements, no_share);
1854 /* If this is last_parm_insn, and any instructions were output
1855 after it to fix it up, then we must set last_parm_insn to
1856 the last such instruction emitted. */
1857 if (insn == last_parm_insn)
1858 last_parm_insn = PREV_INSN (next_insn);
1860 while (replacements)
1862 struct fixup_replacement *next;
1864 if (GET_CODE (replacements->new) == REG)
1869 /* OLD might be a (subreg (mem)). */
1870 if (GET_CODE (replacements->old) == SUBREG)
1872 = fixup_memory_subreg (replacements->old, insn, 0);
1875 = fixup_stack_1 (replacements->old, insn);
1877 insert_before = insn;
1879 /* If we are changing the mode, do a conversion.
1880 This might be wasteful, but combine.c will
1881 eliminate much of the waste. */
1883 if (GET_MODE (replacements->new)
1884 != GET_MODE (replacements->old))
1887 convert_move (replacements->new,
1888 replacements->old, unsignedp);
1889 seq = gen_sequence ();
1893 seq = gen_move_insn (replacements->new,
1896 emit_insn_before (seq, insert_before);
1899 next = replacements->next;
1900 free (replacements);
1901 replacements = next;
1905 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1906 But don't touch other insns referred to by reg-notes;
1907 we will get them elsewhere. */
1910 if (GET_CODE (note) != INSN_LIST)
1912 = walk_fixup_memory_subreg (XEXP (note, 0), insn, 1);
1913 note = XEXP (note, 1);
1917 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1918 See if the rtx expression at *LOC in INSN needs to be changed.
1920 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1921 contain a list of original rtx's and replacements. If we find that we need
1922 to modify this insn by replacing a memory reference with a pseudo or by
1923 making a new MEM to implement a SUBREG, we consult that list to see if
1924 we have already chosen a replacement. If none has already been allocated,
1925 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1926 or the SUBREG, as appropriate, to the pseudo. */
1929 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements, no_share)
1931 enum machine_mode promoted_mode;
1934 struct fixup_replacement **replacements;
1939 RTX_CODE code = GET_CODE (x);
1942 struct fixup_replacement *replacement;
1947 if (XEXP (x, 0) == var)
1949 /* Prevent sharing of rtl that might lose. */
1950 rtx sub = copy_rtx (XEXP (var, 0));
1952 if (! validate_change (insn, loc, sub, 0))
1954 rtx y = gen_reg_rtx (GET_MODE (sub));
1957 /* We should be able to replace with a register or all is lost.
1958 Note that we can't use validate_change to verify this, since
1959 we're not caring for replacing all dups simultaneously. */
1960 if (! validate_replace_rtx (*loc, y, insn))
1963 /* Careful! First try to recognize a direct move of the
1964 value, mimicking how things are done in gen_reload wrt
1965 PLUS. Consider what happens when insn is a conditional
1966 move instruction and addsi3 clobbers flags. */
1969 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1970 seq = gen_sequence ();
1973 if (recog_memoized (new_insn) < 0)
1975 /* That failed. Fall back on force_operand and hope. */
1978 sub = force_operand (sub, y);
1980 emit_insn (gen_move_insn (y, sub));
1981 seq = gen_sequence ();
1986 /* Don't separate setter from user. */
1987 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1988 insn = PREV_INSN (insn);
1991 emit_insn_before (seq, insn);
1999 /* If we already have a replacement, use it. Otherwise,
2000 try to fix up this address in case it is invalid. */
2002 replacement = find_fixup_replacement (replacements, var);
2003 if (replacement->new)
2005 *loc = replacement->new;
2009 *loc = replacement->new = x = fixup_stack_1 (x, insn);
2011 /* Unless we are forcing memory to register or we changed the mode,
2012 we can leave things the way they are if the insn is valid. */
2014 INSN_CODE (insn) = -1;
2015 if (! flag_force_mem && GET_MODE (x) == promoted_mode
2016 && recog_memoized (insn) >= 0)
2019 *loc = replacement->new = gen_reg_rtx (promoted_mode);
2023 /* If X contains VAR, we need to unshare it here so that we update
2024 each occurrence separately. But all identical MEMs in one insn
2025 must be replaced with the same rtx because of the possibility of
2028 if (reg_mentioned_p (var, x))
2030 replacement = find_fixup_replacement (replacements, x);
2031 if (replacement->new == 0)
2032 replacement->new = copy_most_rtx (x, no_share);
2034 *loc = x = replacement->new;
2035 code = GET_CODE (x);
2052 /* Note that in some cases those types of expressions are altered
2053 by optimize_bit_field, and do not survive to get here. */
2054 if (XEXP (x, 0) == var
2055 || (GET_CODE (XEXP (x, 0)) == SUBREG
2056 && SUBREG_REG (XEXP (x, 0)) == var))
2058 /* Get TEM as a valid MEM in the mode presently in the insn.
2060 We don't worry about the possibility of MATCH_DUP here; it
2061 is highly unlikely and would be tricky to handle. */
2064 if (GET_CODE (tem) == SUBREG)
2066 if (GET_MODE_BITSIZE (GET_MODE (tem))
2067 > GET_MODE_BITSIZE (GET_MODE (var)))
2069 replacement = find_fixup_replacement (replacements, var);
2070 if (replacement->new == 0)
2071 replacement->new = gen_reg_rtx (GET_MODE (var));
2072 SUBREG_REG (tem) = replacement->new;
2074 /* The following code works only if we have a MEM, so we
2075 need to handle the subreg here. We directly substitute
2076 it assuming that a subreg must be OK here. We already
2077 scheduled a replacement to copy the mem into the
2083 tem = fixup_memory_subreg (tem, insn, 0);
2086 tem = fixup_stack_1 (tem, insn);
2088 /* Unless we want to load from memory, get TEM into the proper mode
2089 for an extract from memory. This can only be done if the
2090 extract is at a constant position and length. */
2092 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2093 && GET_CODE (XEXP (x, 2)) == CONST_INT
2094 && ! mode_dependent_address_p (XEXP (tem, 0))
2095 && ! MEM_VOLATILE_P (tem))
2097 enum machine_mode wanted_mode = VOIDmode;
2098 enum machine_mode is_mode = GET_MODE (tem);
2099 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2101 if (GET_CODE (x) == ZERO_EXTRACT)
2103 enum machine_mode new_mode
2104 = mode_for_extraction (EP_extzv, 1);
2105 if (new_mode != MAX_MACHINE_MODE)
2106 wanted_mode = new_mode;
2108 else if (GET_CODE (x) == SIGN_EXTRACT)
2110 enum machine_mode new_mode
2111 = mode_for_extraction (EP_extv, 1);
2112 if (new_mode != MAX_MACHINE_MODE)
2113 wanted_mode = new_mode;
2116 /* If we have a narrower mode, we can do something. */
2117 if (wanted_mode != VOIDmode
2118 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2120 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2121 rtx old_pos = XEXP (x, 2);
2124 /* If the bytes and bits are counted differently, we
2125 must adjust the offset. */
2126 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2127 offset = (GET_MODE_SIZE (is_mode)
2128 - GET_MODE_SIZE (wanted_mode) - offset);
2130 pos %= GET_MODE_BITSIZE (wanted_mode);
2132 newmem = adjust_address_nv (tem, wanted_mode, offset);
2134 /* Make the change and see if the insn remains valid. */
2135 INSN_CODE (insn) = -1;
2136 XEXP (x, 0) = newmem;
2137 XEXP (x, 2) = GEN_INT (pos);
2139 if (recog_memoized (insn) >= 0)
2142 /* Otherwise, restore old position. XEXP (x, 0) will be
2144 XEXP (x, 2) = old_pos;
2148 /* If we get here, the bitfield extract insn can't accept a memory
2149 reference. Copy the input into a register. */
2151 tem1 = gen_reg_rtx (GET_MODE (tem));
2152 emit_insn_before (gen_move_insn (tem1, tem), insn);
2159 if (SUBREG_REG (x) == var)
2161 /* If this is a special SUBREG made because VAR was promoted
2162 from a wider mode, replace it with VAR and call ourself
2163 recursively, this time saying that the object previously
2164 had its current mode (by virtue of the SUBREG). */
2166 if (SUBREG_PROMOTED_VAR_P (x))
2169 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements,
2174 /* If this SUBREG makes VAR wider, it has become a paradoxical
2175 SUBREG with VAR in memory, but these aren't allowed at this
2176 stage of the compilation. So load VAR into a pseudo and take
2177 a SUBREG of that pseudo. */
2178 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2180 replacement = find_fixup_replacement (replacements, var);
2181 if (replacement->new == 0)
2182 replacement->new = gen_reg_rtx (promoted_mode);
2183 SUBREG_REG (x) = replacement->new;
2187 /* See if we have already found a replacement for this SUBREG.
2188 If so, use it. Otherwise, make a MEM and see if the insn
2189 is recognized. If not, or if we should force MEM into a register,
2190 make a pseudo for this SUBREG. */
2191 replacement = find_fixup_replacement (replacements, x);
2192 if (replacement->new)
2194 *loc = replacement->new;
2198 replacement->new = *loc = fixup_memory_subreg (x, insn, 0);
2200 INSN_CODE (insn) = -1;
2201 if (! flag_force_mem && recog_memoized (insn) >= 0)
2204 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2210 /* First do special simplification of bit-field references. */
2211 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2212 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2213 optimize_bit_field (x, insn, 0);
2214 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2215 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2216 optimize_bit_field (x, insn, 0);
2218 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2219 into a register and then store it back out. */
2220 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2221 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2222 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2223 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2224 > GET_MODE_SIZE (GET_MODE (var))))
2226 replacement = find_fixup_replacement (replacements, var);
2227 if (replacement->new == 0)
2228 replacement->new = gen_reg_rtx (GET_MODE (var));
2230 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2231 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2234 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2235 insn into a pseudo and store the low part of the pseudo into VAR. */
2236 if (GET_CODE (SET_DEST (x)) == SUBREG
2237 && SUBREG_REG (SET_DEST (x)) == var
2238 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2239 > GET_MODE_SIZE (GET_MODE (var))))
2241 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2242 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2249 rtx dest = SET_DEST (x);
2250 rtx src = SET_SRC (x);
2251 rtx outerdest = dest;
2253 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2254 || GET_CODE (dest) == SIGN_EXTRACT
2255 || GET_CODE (dest) == ZERO_EXTRACT)
2256 dest = XEXP (dest, 0);
2258 if (GET_CODE (src) == SUBREG)
2259 src = SUBREG_REG (src);
2261 /* If VAR does not appear at the top level of the SET
2262 just scan the lower levels of the tree. */
2264 if (src != var && dest != var)
2267 /* We will need to rerecognize this insn. */
2268 INSN_CODE (insn) = -1;
2270 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var
2271 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE)
2273 /* Since this case will return, ensure we fixup all the
2275 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2276 insn, replacements, no_share);
2277 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2278 insn, replacements, no_share);
2279 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2280 insn, replacements, no_share);
2282 tem = XEXP (outerdest, 0);
2284 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2285 that may appear inside a ZERO_EXTRACT.
2286 This was legitimate when the MEM was a REG. */
2287 if (GET_CODE (tem) == SUBREG
2288 && SUBREG_REG (tem) == var)
2289 tem = fixup_memory_subreg (tem, insn, 0);
2291 tem = fixup_stack_1 (tem, insn);
2293 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2294 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2295 && ! mode_dependent_address_p (XEXP (tem, 0))
2296 && ! MEM_VOLATILE_P (tem))
2298 enum machine_mode wanted_mode;
2299 enum machine_mode is_mode = GET_MODE (tem);
2300 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2302 wanted_mode = mode_for_extraction (EP_insv, 0);
2304 /* If we have a narrower mode, we can do something. */
2305 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2307 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2308 rtx old_pos = XEXP (outerdest, 2);
2311 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2312 offset = (GET_MODE_SIZE (is_mode)
2313 - GET_MODE_SIZE (wanted_mode) - offset);
2315 pos %= GET_MODE_BITSIZE (wanted_mode);
2317 newmem = adjust_address_nv (tem, wanted_mode, offset);
2319 /* Make the change and see if the insn remains valid. */
2320 INSN_CODE (insn) = -1;
2321 XEXP (outerdest, 0) = newmem;
2322 XEXP (outerdest, 2) = GEN_INT (pos);
2324 if (recog_memoized (insn) >= 0)
2327 /* Otherwise, restore old position. XEXP (x, 0) will be
2329 XEXP (outerdest, 2) = old_pos;
2333 /* If we get here, the bit-field store doesn't allow memory
2334 or isn't located at a constant position. Load the value into
2335 a register, do the store, and put it back into memory. */
2337 tem1 = gen_reg_rtx (GET_MODE (tem));
2338 emit_insn_before (gen_move_insn (tem1, tem), insn);
2339 emit_insn_after (gen_move_insn (tem, tem1), insn);
2340 XEXP (outerdest, 0) = tem1;
2344 /* STRICT_LOW_PART is a no-op on memory references
2345 and it can cause combinations to be unrecognizable,
2348 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2349 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2351 /* A valid insn to copy VAR into or out of a register
2352 must be left alone, to avoid an infinite loop here.
2353 If the reference to VAR is by a subreg, fix that up,
2354 since SUBREG is not valid for a memref.
2355 Also fix up the address of the stack slot.
2357 Note that we must not try to recognize the insn until
2358 after we know that we have valid addresses and no
2359 (subreg (mem ...) ...) constructs, since these interfere
2360 with determining the validity of the insn. */
2362 if ((SET_SRC (x) == var
2363 || (GET_CODE (SET_SRC (x)) == SUBREG
2364 && SUBREG_REG (SET_SRC (x)) == var))
2365 && (GET_CODE (SET_DEST (x)) == REG
2366 || (GET_CODE (SET_DEST (x)) == SUBREG
2367 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2368 && GET_MODE (var) == promoted_mode
2369 && x == single_set (insn))
2373 if (GET_CODE (SET_SRC (x)) == SUBREG
2374 && (GET_MODE_SIZE (GET_MODE (SET_SRC (x)))
2375 > GET_MODE_SIZE (GET_MODE (var))))
2377 /* This (subreg VAR) is now a paradoxical subreg. We need
2378 to replace VAR instead of the subreg. */
2379 replacement = find_fixup_replacement (replacements, var);
2380 if (replacement->new == NULL_RTX)
2381 replacement->new = gen_reg_rtx (GET_MODE (var));
2382 SUBREG_REG (SET_SRC (x)) = replacement->new;
2386 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2387 if (replacement->new)
2388 SET_SRC (x) = replacement->new;
2389 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2390 SET_SRC (x) = replacement->new
2391 = fixup_memory_subreg (SET_SRC (x), insn, 0);
2393 SET_SRC (x) = replacement->new
2394 = fixup_stack_1 (SET_SRC (x), insn);
2397 if (recog_memoized (insn) >= 0)
2400 /* INSN is not valid, but we know that we want to
2401 copy SET_SRC (x) to SET_DEST (x) in some way. So
2402 we generate the move and see whether it requires more
2403 than one insn. If it does, we emit those insns and
2404 delete INSN. Otherwise, we an just replace the pattern
2405 of INSN; we have already verified above that INSN has
2406 no other function that to do X. */
2408 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2409 if (GET_CODE (pat) == SEQUENCE)
2411 last = emit_insn_before (pat, insn);
2413 /* INSN might have REG_RETVAL or other important notes, so
2414 we need to store the pattern of the last insn in the
2415 sequence into INSN similarly to the normal case. LAST
2416 should not have REG_NOTES, but we allow them if INSN has
2418 if (REG_NOTES (last) && REG_NOTES (insn))
2420 if (REG_NOTES (last))
2421 REG_NOTES (insn) = REG_NOTES (last);
2422 PATTERN (insn) = PATTERN (last);
2427 PATTERN (insn) = pat;
2432 if ((SET_DEST (x) == var
2433 || (GET_CODE (SET_DEST (x)) == SUBREG
2434 && SUBREG_REG (SET_DEST (x)) == var))
2435 && (GET_CODE (SET_SRC (x)) == REG
2436 || (GET_CODE (SET_SRC (x)) == SUBREG
2437 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2438 && GET_MODE (var) == promoted_mode
2439 && x == single_set (insn))
2443 if (GET_CODE (SET_DEST (x)) == SUBREG)
2444 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn, 0);
2446 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2448 if (recog_memoized (insn) >= 0)
2451 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2452 if (GET_CODE (pat) == SEQUENCE)
2454 last = emit_insn_before (pat, insn);
2456 /* INSN might have REG_RETVAL or other important notes, so
2457 we need to store the pattern of the last insn in the
2458 sequence into INSN similarly to the normal case. LAST
2459 should not have REG_NOTES, but we allow them if INSN has
2461 if (REG_NOTES (last) && REG_NOTES (insn))
2463 if (REG_NOTES (last))
2464 REG_NOTES (insn) = REG_NOTES (last);
2465 PATTERN (insn) = PATTERN (last);
2470 PATTERN (insn) = pat;
2475 /* Otherwise, storing into VAR must be handled specially
2476 by storing into a temporary and copying that into VAR
2477 with a new insn after this one. Note that this case
2478 will be used when storing into a promoted scalar since
2479 the insn will now have different modes on the input
2480 and output and hence will be invalid (except for the case
2481 of setting it to a constant, which does not need any
2482 change if it is valid). We generate extra code in that case,
2483 but combine.c will eliminate it. */
2488 rtx fixeddest = SET_DEST (x);
2490 /* STRICT_LOW_PART can be discarded, around a MEM. */
2491 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2492 fixeddest = XEXP (fixeddest, 0);
2493 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2494 if (GET_CODE (fixeddest) == SUBREG)
2496 fixeddest = fixup_memory_subreg (fixeddest, insn, 0);
2497 promoted_mode = GET_MODE (fixeddest);
2500 fixeddest = fixup_stack_1 (fixeddest, insn);
2502 temp = gen_reg_rtx (promoted_mode);
2504 emit_insn_after (gen_move_insn (fixeddest,
2505 gen_lowpart (GET_MODE (fixeddest),
2509 SET_DEST (x) = temp;
2517 /* Nothing special about this RTX; fix its operands. */
2519 fmt = GET_RTX_FORMAT (code);
2520 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2523 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements,
2525 else if (fmt[i] == 'E')
2528 for (j = 0; j < XVECLEN (x, i); j++)
2529 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2530 insn, replacements, no_share);
2535 /* Given X, an rtx of the form (SUBREG:m1 (MEM:m2 addr)),
2536 return an rtx (MEM:m1 newaddr) which is equivalent.
2537 If any insns must be emitted to compute NEWADDR, put them before INSN.
2539 UNCRITICAL nonzero means accept paradoxical subregs.
2540 This is used for subregs found inside REG_NOTES. */
2543 fixup_memory_subreg (x, insn, uncritical)
2548 int offset = SUBREG_BYTE (x);
2549 rtx addr = XEXP (SUBREG_REG (x), 0);
2550 enum machine_mode mode = GET_MODE (x);
2553 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2554 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))
2558 if (!flag_force_addr
2559 && memory_address_p (mode, plus_constant (addr, offset)))
2560 /* Shortcut if no insns need be emitted. */
2561 return adjust_address (SUBREG_REG (x), mode, offset);
2564 result = adjust_address (SUBREG_REG (x), mode, offset);
2565 emit_insn_before (gen_sequence (), insn);
2570 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2571 Replace subexpressions of X in place.
2572 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2573 Otherwise return X, with its contents possibly altered.
2575 If any insns must be emitted to compute NEWADDR, put them before INSN.
2577 UNCRITICAL is as in fixup_memory_subreg. */
2580 walk_fixup_memory_subreg (x, insn, uncritical)
2592 code = GET_CODE (x);
2594 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2595 return fixup_memory_subreg (x, insn, uncritical);
2597 /* Nothing special about this RTX; fix its operands. */
2599 fmt = GET_RTX_FORMAT (code);
2600 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2603 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn, uncritical);
2604 else if (fmt[i] == 'E')
2607 for (j = 0; j < XVECLEN (x, i); j++)
2609 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn, uncritical);
2615 /* For each memory ref within X, if it refers to a stack slot
2616 with an out of range displacement, put the address in a temp register
2617 (emitting new insns before INSN to load these registers)
2618 and alter the memory ref to use that register.
2619 Replace each such MEM rtx with a copy, to avoid clobberage. */
2622 fixup_stack_1 (x, insn)
2627 RTX_CODE code = GET_CODE (x);
2632 rtx ad = XEXP (x, 0);
2633 /* If we have address of a stack slot but it's not valid
2634 (displacement is too large), compute the sum in a register. */
2635 if (GET_CODE (ad) == PLUS
2636 && GET_CODE (XEXP (ad, 0)) == REG
2637 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2638 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2639 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2640 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2641 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2643 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2644 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2645 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2646 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2649 if (memory_address_p (GET_MODE (x), ad))
2653 temp = copy_to_reg (ad);
2654 seq = gen_sequence ();
2656 emit_insn_before (seq, insn);
2657 return replace_equiv_address (x, temp);
2662 fmt = GET_RTX_FORMAT (code);
2663 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2666 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2667 else if (fmt[i] == 'E')
2670 for (j = 0; j < XVECLEN (x, i); j++)
2671 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2677 /* Optimization: a bit-field instruction whose field
2678 happens to be a byte or halfword in memory
2679 can be changed to a move instruction.
2681 We call here when INSN is an insn to examine or store into a bit-field.
2682 BODY is the SET-rtx to be altered.
2684 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2685 (Currently this is called only from function.c, and EQUIV_MEM
2689 optimize_bit_field (body, insn, equiv_mem)
2697 enum machine_mode mode;
2699 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2700 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2701 bitfield = SET_DEST (body), destflag = 1;
2703 bitfield = SET_SRC (body), destflag = 0;
2705 /* First check that the field being stored has constant size and position
2706 and is in fact a byte or halfword suitably aligned. */
2708 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2709 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2710 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2712 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2716 /* Now check that the containing word is memory, not a register,
2717 and that it is safe to change the machine mode. */
2719 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2720 memref = XEXP (bitfield, 0);
2721 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2723 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2724 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2725 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2726 memref = SUBREG_REG (XEXP (bitfield, 0));
2727 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2729 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2730 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2733 && ! mode_dependent_address_p (XEXP (memref, 0))
2734 && ! MEM_VOLATILE_P (memref))
2736 /* Now adjust the address, first for any subreg'ing
2737 that we are now getting rid of,
2738 and then for which byte of the word is wanted. */
2740 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2743 /* Adjust OFFSET to count bits from low-address byte. */
2744 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2745 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2746 - offset - INTVAL (XEXP (bitfield, 1)));
2748 /* Adjust OFFSET to count bytes from low-address byte. */
2749 offset /= BITS_PER_UNIT;
2750 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2752 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2753 / UNITS_PER_WORD) * UNITS_PER_WORD;
2754 if (BYTES_BIG_ENDIAN)
2755 offset -= (MIN (UNITS_PER_WORD,
2756 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2757 - MIN (UNITS_PER_WORD,
2758 GET_MODE_SIZE (GET_MODE (memref))));
2762 memref = adjust_address (memref, mode, offset);
2763 insns = get_insns ();
2765 emit_insns_before (insns, insn);
2767 /* Store this memory reference where
2768 we found the bit field reference. */
2772 validate_change (insn, &SET_DEST (body), memref, 1);
2773 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2775 rtx src = SET_SRC (body);
2776 while (GET_CODE (src) == SUBREG
2777 && SUBREG_BYTE (src) == 0)
2778 src = SUBREG_REG (src);
2779 if (GET_MODE (src) != GET_MODE (memref))
2780 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2781 validate_change (insn, &SET_SRC (body), src, 1);
2783 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2784 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2785 /* This shouldn't happen because anything that didn't have
2786 one of these modes should have got converted explicitly
2787 and then referenced through a subreg.
2788 This is so because the original bit-field was
2789 handled by agg_mode and so its tree structure had
2790 the same mode that memref now has. */
2795 rtx dest = SET_DEST (body);
2797 while (GET_CODE (dest) == SUBREG
2798 && SUBREG_BYTE (dest) == 0
2799 && (GET_MODE_CLASS (GET_MODE (dest))
2800 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2801 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2803 dest = SUBREG_REG (dest);
2805 validate_change (insn, &SET_DEST (body), dest, 1);
2807 if (GET_MODE (dest) == GET_MODE (memref))
2808 validate_change (insn, &SET_SRC (body), memref, 1);
2811 /* Convert the mem ref to the destination mode. */
2812 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2815 convert_move (newreg, memref,
2816 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2820 validate_change (insn, &SET_SRC (body), newreg, 1);
2824 /* See if we can convert this extraction or insertion into
2825 a simple move insn. We might not be able to do so if this
2826 was, for example, part of a PARALLEL.
2828 If we succeed, write out any needed conversions. If we fail,
2829 it is hard to guess why we failed, so don't do anything
2830 special; just let the optimization be suppressed. */
2832 if (apply_change_group () && seq)
2833 emit_insns_before (seq, insn);
2838 /* These routines are responsible for converting virtual register references
2839 to the actual hard register references once RTL generation is complete.
2841 The following four variables are used for communication between the
2842 routines. They contain the offsets of the virtual registers from their
2843 respective hard registers. */
2845 static int in_arg_offset;
2846 static int var_offset;
2847 static int dynamic_offset;
2848 static int out_arg_offset;
2849 static int cfa_offset;
2851 /* In most machines, the stack pointer register is equivalent to the bottom
2854 #ifndef STACK_POINTER_OFFSET
2855 #define STACK_POINTER_OFFSET 0
2858 /* If not defined, pick an appropriate default for the offset of dynamically
2859 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2860 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2862 #ifndef STACK_DYNAMIC_OFFSET
2864 /* The bottom of the stack points to the actual arguments. If
2865 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2866 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2867 stack space for register parameters is not pushed by the caller, but
2868 rather part of the fixed stack areas and hence not included in
2869 `current_function_outgoing_args_size'. Nevertheless, we must allow
2870 for it when allocating stack dynamic objects. */
2872 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2873 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2874 ((ACCUMULATE_OUTGOING_ARGS \
2875 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2876 + (STACK_POINTER_OFFSET)) \
2879 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2880 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2881 + (STACK_POINTER_OFFSET))
2885 /* On most machines, the CFA coincides with the first incoming parm. */
2887 #ifndef ARG_POINTER_CFA_OFFSET
2888 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2891 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had its
2892 address taken. DECL is the decl or SAVE_EXPR for the object stored in the
2893 register, for later use if we do need to force REG into the stack. REG is
2894 overwritten by the MEM like in put_reg_into_stack. */
2897 gen_mem_addressof (reg, decl)
2901 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2904 /* Calculate this before we start messing with decl's RTL. */
2905 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0;
2907 /* If the original REG was a user-variable, then so is the REG whose
2908 address is being taken. Likewise for unchanging. */
2909 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2910 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2912 PUT_CODE (reg, MEM);
2913 MEM_ATTRS (reg) = 0;
2918 tree type = TREE_TYPE (decl);
2919 enum machine_mode decl_mode
2920 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl)));
2921 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl)
2922 : DECL_RTL_IF_SET (decl));
2924 PUT_MODE (reg, decl_mode);
2926 /* Clear DECL_RTL momentarily so functions below will work
2927 properly, then set it again. */
2928 if (DECL_P (decl) && decl_rtl == reg)
2929 SET_DECL_RTL (decl, 0);
2931 set_mem_attributes (reg, decl, 1);
2932 set_mem_alias_set (reg, set);
2934 if (DECL_P (decl) && decl_rtl == reg)
2935 SET_DECL_RTL (decl, reg);
2937 if (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0))
2938 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), reg, 0);
2941 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0);
2946 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2949 flush_addressof (decl)
2952 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2953 && DECL_RTL (decl) != 0
2954 && GET_CODE (DECL_RTL (decl)) == MEM
2955 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2956 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2957 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2960 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2963 put_addressof_into_stack (r, ht)
2965 struct hash_table *ht;
2968 int volatile_p, used_p;
2970 rtx reg = XEXP (r, 0);
2972 if (GET_CODE (reg) != REG)
2975 decl = ADDRESSOF_DECL (r);
2978 type = TREE_TYPE (decl);
2979 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2980 && TREE_THIS_VOLATILE (decl));
2981 used_p = (TREE_USED (decl)
2982 || (DECL_P (decl) && DECL_INITIAL (decl) != 0));
2991 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2992 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2995 /* List of replacements made below in purge_addressof_1 when creating
2996 bitfield insertions. */
2997 static rtx purge_bitfield_addressof_replacements;
2999 /* List of replacements made below in purge_addressof_1 for patterns
3000 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
3001 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
3002 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
3003 enough in complex cases, e.g. when some field values can be
3004 extracted by usage MEM with narrower mode. */
3005 static rtx purge_addressof_replacements;
3007 /* Helper function for purge_addressof. See if the rtx expression at *LOC
3008 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
3009 the stack. If the function returns FALSE then the replacement could not
3013 purge_addressof_1 (loc, insn, force, store, ht)
3017 struct hash_table *ht;
3025 /* Re-start here to avoid recursion in common cases. */
3032 code = GET_CODE (x);
3034 /* If we don't return in any of the cases below, we will recurse inside
3035 the RTX, which will normally result in any ADDRESSOF being forced into
3039 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
3040 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
3043 else if (code == ADDRESSOF)
3047 if (GET_CODE (XEXP (x, 0)) != MEM)
3049 put_addressof_into_stack (x, ht);
3053 /* We must create a copy of the rtx because it was created by
3054 overwriting a REG rtx which is always shared. */
3055 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
3056 if (validate_change (insn, loc, sub, 0)
3057 || validate_replace_rtx (x, sub, insn))
3061 sub = force_operand (sub, NULL_RTX);
3062 if (! validate_change (insn, loc, sub, 0)
3063 && ! validate_replace_rtx (x, sub, insn))
3066 insns = gen_sequence ();
3068 emit_insn_before (insns, insn);
3072 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3074 rtx sub = XEXP (XEXP (x, 0), 0);
3076 if (GET_CODE (sub) == MEM)
3077 sub = adjust_address_nv (sub, GET_MODE (x), 0);
3078 else if (GET_CODE (sub) == REG
3079 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3081 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3083 int size_x, size_sub;
3087 /* When processing REG_NOTES look at the list of
3088 replacements done on the insn to find the register that X
3092 for (tem = purge_bitfield_addressof_replacements;
3094 tem = XEXP (XEXP (tem, 1), 1))
3095 if (rtx_equal_p (x, XEXP (tem, 0)))
3097 *loc = XEXP (XEXP (tem, 1), 0);
3101 /* See comment for purge_addressof_replacements. */
3102 for (tem = purge_addressof_replacements;
3104 tem = XEXP (XEXP (tem, 1), 1))
3105 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3107 rtx z = XEXP (XEXP (tem, 1), 0);
3109 if (GET_MODE (x) == GET_MODE (z)
3110 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3111 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3114 /* It can happen that the note may speak of things
3115 in a wider (or just different) mode than the
3116 code did. This is especially true of
3119 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3122 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3123 && (GET_MODE_SIZE (GET_MODE (x))
3124 > GET_MODE_SIZE (GET_MODE (z))))
3126 /* This can occur as a result in invalid
3127 pointer casts, e.g. float f; ...
3128 *(long long int *)&f.
3129 ??? We could emit a warning here, but
3130 without a line number that wouldn't be
3132 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3135 z = gen_lowpart (GET_MODE (x), z);
3141 /* Sometimes we may not be able to find the replacement. For
3142 example when the original insn was a MEM in a wider mode,
3143 and the note is part of a sign extension of a narrowed
3144 version of that MEM. Gcc testcase compile/990829-1.c can
3145 generate an example of this situation. Rather than complain
3146 we return false, which will prompt our caller to remove the
3151 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3152 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3154 /* Don't even consider working with paradoxical subregs,
3155 or the moral equivalent seen here. */
3156 if (size_x <= size_sub
3157 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3159 /* Do a bitfield insertion to mirror what would happen
3166 rtx p = PREV_INSN (insn);
3169 val = gen_reg_rtx (GET_MODE (x));
3170 if (! validate_change (insn, loc, val, 0))
3172 /* Discard the current sequence and put the
3173 ADDRESSOF on stack. */
3177 seq = gen_sequence ();
3179 emit_insn_before (seq, insn);
3180 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3184 store_bit_field (sub, size_x, 0, GET_MODE (x),
3185 val, GET_MODE_SIZE (GET_MODE (sub)));
3187 /* Make sure to unshare any shared rtl that store_bit_field
3188 might have created. */
3189 unshare_all_rtl_again (get_insns ());
3191 seq = gen_sequence ();
3193 p = emit_insn_after (seq, insn);
3194 if (NEXT_INSN (insn))
3195 compute_insns_for_mem (NEXT_INSN (insn),
3196 p ? NEXT_INSN (p) : NULL_RTX,
3201 rtx p = PREV_INSN (insn);
3204 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3205 GET_MODE (x), GET_MODE (x),
3206 GET_MODE_SIZE (GET_MODE (sub)));
3208 if (! validate_change (insn, loc, val, 0))
3210 /* Discard the current sequence and put the
3211 ADDRESSOF on stack. */
3216 seq = gen_sequence ();
3218 emit_insn_before (seq, insn);
3219 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3223 /* Remember the replacement so that the same one can be done
3224 on the REG_NOTES. */
3225 purge_bitfield_addressof_replacements
3226 = gen_rtx_EXPR_LIST (VOIDmode, x,
3229 purge_bitfield_addressof_replacements));
3231 /* We replaced with a reg -- all done. */
3236 else if (validate_change (insn, loc, sub, 0))
3238 /* Remember the replacement so that the same one can be done
3239 on the REG_NOTES. */
3240 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3244 for (tem = purge_addressof_replacements;
3246 tem = XEXP (XEXP (tem, 1), 1))
3247 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3249 XEXP (XEXP (tem, 1), 0) = sub;
3252 purge_addressof_replacements
3253 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3254 gen_rtx_EXPR_LIST (VOIDmode, sub,
3255 purge_addressof_replacements));
3263 /* Scan all subexpressions. */
3264 fmt = GET_RTX_FORMAT (code);
3265 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3268 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0, ht);
3269 else if (*fmt == 'E')
3270 for (j = 0; j < XVECLEN (x, i); j++)
3271 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, ht);
3277 /* Return a new hash table entry in HT. */
3279 static struct hash_entry *
3280 insns_for_mem_newfunc (he, ht, k)
3281 struct hash_entry *he;
3282 struct hash_table *ht;
3283 hash_table_key k ATTRIBUTE_UNUSED;
3285 struct insns_for_mem_entry *ifmhe;
3289 ifmhe = ((struct insns_for_mem_entry *)
3290 hash_allocate (ht, sizeof (struct insns_for_mem_entry)));
3291 ifmhe->insns = NULL_RTX;
3296 /* Return a hash value for K, a REG. */
3298 static unsigned long
3299 insns_for_mem_hash (k)
3302 /* K is really a RTX. Just use the address as the hash value. */
3303 return (unsigned long) k;
3306 /* Return non-zero if K1 and K2 (two REGs) are the same. */
3309 insns_for_mem_comp (k1, k2)
3316 struct insns_for_mem_walk_info
3318 /* The hash table that we are using to record which INSNs use which
3320 struct hash_table *ht;
3322 /* The INSN we are currently processing. */
3325 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3326 to find the insns that use the REGs in the ADDRESSOFs. */
3330 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3331 that might be used in an ADDRESSOF expression, record this INSN in
3332 the hash table given by DATA (which is really a pointer to an
3333 insns_for_mem_walk_info structure). */
3336 insns_for_mem_walk (r, data)
3340 struct insns_for_mem_walk_info *ifmwi
3341 = (struct insns_for_mem_walk_info *) data;
3343 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3344 && GET_CODE (XEXP (*r, 0)) == REG)
3345 hash_lookup (ifmwi->ht, XEXP (*r, 0), /*create=*/1, /*copy=*/0);
3346 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3348 /* Lookup this MEM in the hashtable, creating it if necessary. */
3349 struct insns_for_mem_entry *ifme
3350 = (struct insns_for_mem_entry *) hash_lookup (ifmwi->ht,
3355 /* If we have not already recorded this INSN, do so now. Since
3356 we process the INSNs in order, we know that if we have
3357 recorded it it must be at the front of the list. */
3358 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3359 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3366 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3367 which REGs in HT. */
3370 compute_insns_for_mem (insns, last_insn, ht)
3373 struct hash_table *ht;
3376 struct insns_for_mem_walk_info ifmwi;
3379 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3380 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3384 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3388 /* Helper function for purge_addressof called through for_each_rtx.
3389 Returns true iff the rtl is an ADDRESSOF. */
3392 is_addressof (rtl, data)
3394 void *data ATTRIBUTE_UNUSED;
3396 return GET_CODE (*rtl) == ADDRESSOF;
3399 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3400 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3404 purge_addressof (insns)
3408 struct hash_table ht;
3410 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3411 requires a fixup pass over the instruction stream to correct
3412 INSNs that depended on the REG being a REG, and not a MEM. But,
3413 these fixup passes are slow. Furthermore, most MEMs are not
3414 mentioned in very many instructions. So, we speed up the process
3415 by pre-calculating which REGs occur in which INSNs; that allows
3416 us to perform the fixup passes much more quickly. */
3417 hash_table_init (&ht,
3418 insns_for_mem_newfunc,
3420 insns_for_mem_comp);
3421 compute_insns_for_mem (insns, NULL_RTX, &ht);
3423 for (insn = insns; insn; insn = NEXT_INSN (insn))
3424 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3425 || GET_CODE (insn) == CALL_INSN)
3427 if (! purge_addressof_1 (&PATTERN (insn), insn,
3428 asm_noperands (PATTERN (insn)) > 0, 0, &ht))
3429 /* If we could not replace the ADDRESSOFs in the insn,
3430 something is wrong. */
3433 if (! purge_addressof_1 (®_NOTES (insn), NULL_RTX, 0, 0, &ht))
3435 /* If we could not replace the ADDRESSOFs in the insn's notes,
3436 we can just remove the offending notes instead. */
3439 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3441 /* If we find a REG_RETVAL note then the insn is a libcall.
3442 Such insns must have REG_EQUAL notes as well, in order
3443 for later passes of the compiler to work. So it is not
3444 safe to delete the notes here, and instead we abort. */
3445 if (REG_NOTE_KIND (note) == REG_RETVAL)
3447 if (for_each_rtx (¬e, is_addressof, NULL))
3448 remove_note (insn, note);
3454 hash_table_free (&ht);
3455 purge_bitfield_addressof_replacements = 0;
3456 purge_addressof_replacements = 0;
3458 /* REGs are shared. purge_addressof will destructively replace a REG
3459 with a MEM, which creates shared MEMs.
3461 Unfortunately, the children of put_reg_into_stack assume that MEMs
3462 referring to the same stack slot are shared (fixup_var_refs and
3463 the associated hash table code).
3465 So, we have to do another unsharing pass after we have flushed any
3466 REGs that had their address taken into the stack.
3468 It may be worth tracking whether or not we converted any REGs into
3469 MEMs to avoid this overhead when it is not needed. */
3470 unshare_all_rtl_again (get_insns ());
3473 /* Convert a SET of a hard subreg to a set of the appropriate hard
3474 register. A subroutine of purge_hard_subreg_sets. */
3477 purge_single_hard_subreg_set (pattern)
3480 rtx reg = SET_DEST (pattern);
3481 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3484 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3485 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3487 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3488 GET_MODE (SUBREG_REG (reg)),
3491 reg = SUBREG_REG (reg);
3495 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3497 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3498 SET_DEST (pattern) = reg;
3502 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3503 only such SETs that we expect to see are those left in because
3504 integrate can't handle sets of parts of a return value register.
3506 We don't use alter_subreg because we only want to eliminate subregs
3507 of hard registers. */
3510 purge_hard_subreg_sets (insn)
3513 for (; insn; insn = NEXT_INSN (insn))
3517 rtx pattern = PATTERN (insn);
3518 switch (GET_CODE (pattern))
3521 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3522 purge_single_hard_subreg_set (pattern);
3527 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3529 rtx inner_pattern = XVECEXP (pattern, 0, j);
3530 if (GET_CODE (inner_pattern) == SET
3531 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3532 purge_single_hard_subreg_set (inner_pattern);
3543 /* Pass through the INSNS of function FNDECL and convert virtual register
3544 references to hard register references. */
3547 instantiate_virtual_regs (fndecl, insns)
3554 /* Compute the offsets to use for this function. */
3555 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3556 var_offset = STARTING_FRAME_OFFSET;
3557 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3558 out_arg_offset = STACK_POINTER_OFFSET;
3559 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3561 /* Scan all variables and parameters of this function. For each that is
3562 in memory, instantiate all virtual registers if the result is a valid
3563 address. If not, we do it later. That will handle most uses of virtual
3564 regs on many machines. */
3565 instantiate_decls (fndecl, 1);
3567 /* Initialize recognition, indicating that volatile is OK. */
3570 /* Scan through all the insns, instantiating every virtual register still
3572 for (insn = insns; insn; insn = NEXT_INSN (insn))
3573 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3574 || GET_CODE (insn) == CALL_INSN)
3576 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3577 instantiate_virtual_regs_1 (®_NOTES (insn), NULL_RTX, 0);
3578 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3579 if (GET_CODE (insn) == CALL_INSN)
3580 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3584 /* Instantiate the stack slots for the parm registers, for later use in
3585 addressof elimination. */
3586 for (i = 0; i < max_parm_reg; ++i)
3587 if (parm_reg_stack_loc[i])
3588 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3590 /* Now instantiate the remaining register equivalences for debugging info.
3591 These will not be valid addresses. */
3592 instantiate_decls (fndecl, 0);
3594 /* Indicate that, from now on, assign_stack_local should use
3595 frame_pointer_rtx. */
3596 virtuals_instantiated = 1;
3599 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3600 all virtual registers in their DECL_RTL's.
3602 If VALID_ONLY, do this only if the resulting address is still valid.
3603 Otherwise, always do it. */
3606 instantiate_decls (fndecl, valid_only)
3612 /* Process all parameters of the function. */
3613 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3615 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3616 HOST_WIDE_INT size_rtl;
3618 instantiate_decl (DECL_RTL (decl), size, valid_only);
3620 /* If the parameter was promoted, then the incoming RTL mode may be
3621 larger than the declared type size. We must use the larger of
3623 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3624 size = MAX (size_rtl, size);
3625 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3628 /* Now process all variables defined in the function or its subblocks. */
3629 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3632 /* Subroutine of instantiate_decls: Process all decls in the given
3633 BLOCK node and all its subblocks. */
3636 instantiate_decls_1 (let, valid_only)
3642 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3643 if (DECL_RTL_SET_P (t))
3644 instantiate_decl (DECL_RTL (t),
3645 int_size_in_bytes (TREE_TYPE (t)),
3648 /* Process all subblocks. */
3649 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3650 instantiate_decls_1 (t, valid_only);
3653 /* Subroutine of the preceding procedures: Given RTL representing a
3654 decl and the size of the object, do any instantiation required.
3656 If VALID_ONLY is non-zero, it means that the RTL should only be
3657 changed if the new address is valid. */
3660 instantiate_decl (x, size, valid_only)
3665 enum machine_mode mode;
3668 /* If this is not a MEM, no need to do anything. Similarly if the
3669 address is a constant or a register that is not a virtual register. */
3671 if (x == 0 || GET_CODE (x) != MEM)
3675 if (CONSTANT_P (addr)
3676 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3677 || (GET_CODE (addr) == REG
3678 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3679 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3682 /* If we should only do this if the address is valid, copy the address.
3683 We need to do this so we can undo any changes that might make the
3684 address invalid. This copy is unfortunate, but probably can't be
3688 addr = copy_rtx (addr);
3690 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3692 if (valid_only && size >= 0)
3694 unsigned HOST_WIDE_INT decl_size = size;
3696 /* Now verify that the resulting address is valid for every integer or
3697 floating-point mode up to and including SIZE bytes long. We do this
3698 since the object might be accessed in any mode and frame addresses
3701 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3702 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3703 mode = GET_MODE_WIDER_MODE (mode))
3704 if (! memory_address_p (mode, addr))
3707 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3708 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3709 mode = GET_MODE_WIDER_MODE (mode))
3710 if (! memory_address_p (mode, addr))
3714 /* Put back the address now that we have updated it and we either know
3715 it is valid or we don't care whether it is valid. */
3720 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3721 is a virtual register, return the equivalent hard register and set the
3722 offset indirectly through the pointer. Otherwise, return 0. */
3725 instantiate_new_reg (x, poffset)
3727 HOST_WIDE_INT *poffset;
3730 HOST_WIDE_INT offset;
3732 if (x == virtual_incoming_args_rtx)
3733 new = arg_pointer_rtx, offset = in_arg_offset;
3734 else if (x == virtual_stack_vars_rtx)
3735 new = frame_pointer_rtx, offset = var_offset;
3736 else if (x == virtual_stack_dynamic_rtx)
3737 new = stack_pointer_rtx, offset = dynamic_offset;
3738 else if (x == virtual_outgoing_args_rtx)
3739 new = stack_pointer_rtx, offset = out_arg_offset;
3740 else if (x == virtual_cfa_rtx)
3741 new = arg_pointer_rtx, offset = cfa_offset;
3749 /* Given a pointer to a piece of rtx and an optional pointer to the
3750 containing object, instantiate any virtual registers present in it.
3752 If EXTRA_INSNS, we always do the replacement and generate
3753 any extra insns before OBJECT. If it zero, we do nothing if replacement
3756 Return 1 if we either had nothing to do or if we were able to do the
3757 needed replacement. Return 0 otherwise; we only return zero if
3758 EXTRA_INSNS is zero.
3760 We first try some simple transformations to avoid the creation of extra
3764 instantiate_virtual_regs_1 (loc, object, extra_insns)
3772 HOST_WIDE_INT offset = 0;
3778 /* Re-start here to avoid recursion in common cases. */
3785 code = GET_CODE (x);
3787 /* Check for some special cases. */
3805 /* We are allowed to set the virtual registers. This means that
3806 the actual register should receive the source minus the
3807 appropriate offset. This is used, for example, in the handling
3808 of non-local gotos. */
3809 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3811 rtx src = SET_SRC (x);
3813 /* We are setting the register, not using it, so the relevant
3814 offset is the negative of the offset to use were we using
3817 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3819 /* The only valid sources here are PLUS or REG. Just do
3820 the simplest possible thing to handle them. */
3821 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3825 if (GET_CODE (src) != REG)
3826 temp = force_operand (src, NULL_RTX);
3829 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3833 emit_insns_before (seq, object);
3836 if (! validate_change (object, &SET_SRC (x), temp, 0)
3843 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3848 /* Handle special case of virtual register plus constant. */
3849 if (CONSTANT_P (XEXP (x, 1)))
3851 rtx old, new_offset;
3853 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3854 if (GET_CODE (XEXP (x, 0)) == PLUS)
3856 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3858 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3860 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3869 #ifdef POINTERS_EXTEND_UNSIGNED
3870 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3871 we can commute the PLUS and SUBREG because pointers into the
3872 frame are well-behaved. */
3873 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3874 && GET_CODE (XEXP (x, 1)) == CONST_INT
3876 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3878 && validate_change (object, loc,
3879 plus_constant (gen_lowpart (ptr_mode,
3882 + INTVAL (XEXP (x, 1))),
3886 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3888 /* We know the second operand is a constant. Unless the
3889 first operand is a REG (which has been already checked),
3890 it needs to be checked. */
3891 if (GET_CODE (XEXP (x, 0)) != REG)
3899 new_offset = plus_constant (XEXP (x, 1), offset);
3901 /* If the new constant is zero, try to replace the sum with just
3903 if (new_offset == const0_rtx
3904 && validate_change (object, loc, new, 0))
3907 /* Next try to replace the register and new offset.
3908 There are two changes to validate here and we can't assume that
3909 in the case of old offset equals new just changing the register
3910 will yield a valid insn. In the interests of a little efficiency,
3911 however, we only call validate change once (we don't queue up the
3912 changes and then call apply_change_group). */
3916 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3917 : (XEXP (x, 0) = new,
3918 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3926 /* Otherwise copy the new constant into a register and replace
3927 constant with that register. */
3928 temp = gen_reg_rtx (Pmode);
3930 if (validate_change (object, &XEXP (x, 1), temp, 0))
3931 emit_insn_before (gen_move_insn (temp, new_offset), object);
3934 /* If that didn't work, replace this expression with a
3935 register containing the sum. */
3938 new = gen_rtx_PLUS (Pmode, new, new_offset);
3941 temp = force_operand (new, NULL_RTX);
3945 emit_insns_before (seq, object);
3946 if (! validate_change (object, loc, temp, 0)
3947 && ! validate_replace_rtx (x, temp, object))
3955 /* Fall through to generic two-operand expression case. */
3961 case DIV: case UDIV:
3962 case MOD: case UMOD:
3963 case AND: case IOR: case XOR:
3964 case ROTATERT: case ROTATE:
3965 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3967 case GE: case GT: case GEU: case GTU:
3968 case LE: case LT: case LEU: case LTU:
3969 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3970 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3975 /* Most cases of MEM that convert to valid addresses have already been
3976 handled by our scan of decls. The only special handling we
3977 need here is to make a copy of the rtx to ensure it isn't being
3978 shared if we have to change it to a pseudo.
3980 If the rtx is a simple reference to an address via a virtual register,
3981 it can potentially be shared. In such cases, first try to make it
3982 a valid address, which can also be shared. Otherwise, copy it and
3985 First check for common cases that need no processing. These are
3986 usually due to instantiation already being done on a previous instance
3990 if (CONSTANT_ADDRESS_P (temp)
3991 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3992 || temp == arg_pointer_rtx
3994 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3995 || temp == hard_frame_pointer_rtx
3997 || temp == frame_pointer_rtx)
4000 if (GET_CODE (temp) == PLUS
4001 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4002 && (XEXP (temp, 0) == frame_pointer_rtx
4003 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4004 || XEXP (temp, 0) == hard_frame_pointer_rtx
4006 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4007 || XEXP (temp, 0) == arg_pointer_rtx
4012 if (temp == virtual_stack_vars_rtx
4013 || temp == virtual_incoming_args_rtx
4014 || (GET_CODE (temp) == PLUS
4015 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
4016 && (XEXP (temp, 0) == virtual_stack_vars_rtx
4017 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
4019 /* This MEM may be shared. If the substitution can be done without
4020 the need to generate new pseudos, we want to do it in place
4021 so all copies of the shared rtx benefit. The call below will
4022 only make substitutions if the resulting address is still
4025 Note that we cannot pass X as the object in the recursive call
4026 since the insn being processed may not allow all valid
4027 addresses. However, if we were not passed on object, we can
4028 only modify X without copying it if X will have a valid
4031 ??? Also note that this can still lose if OBJECT is an insn that
4032 has less restrictions on an address that some other insn.
4033 In that case, we will modify the shared address. This case
4034 doesn't seem very likely, though. One case where this could
4035 happen is in the case of a USE or CLOBBER reference, but we
4036 take care of that below. */
4038 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
4039 object ? object : x, 0))
4042 /* Otherwise make a copy and process that copy. We copy the entire
4043 RTL expression since it might be a PLUS which could also be
4045 *loc = x = copy_rtx (x);
4048 /* Fall through to generic unary operation case. */
4051 case STRICT_LOW_PART:
4053 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4054 case SIGN_EXTEND: case ZERO_EXTEND:
4055 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4056 case FLOAT: case FIX:
4057 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4061 /* These case either have just one operand or we know that we need not
4062 check the rest of the operands. */
4068 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4069 go ahead and make the invalid one, but do it to a copy. For a REG,
4070 just make the recursive call, since there's no chance of a problem. */
4072 if ((GET_CODE (XEXP (x, 0)) == MEM
4073 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4075 || (GET_CODE (XEXP (x, 0)) == REG
4076 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4079 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4084 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4085 in front of this insn and substitute the temporary. */
4086 if ((new = instantiate_new_reg (x, &offset)) != 0)
4088 temp = plus_constant (new, offset);
4089 if (!validate_change (object, loc, temp, 0))
4095 temp = force_operand (temp, NULL_RTX);
4099 emit_insns_before (seq, object);
4100 if (! validate_change (object, loc, temp, 0)
4101 && ! validate_replace_rtx (x, temp, object))
4109 if (GET_CODE (XEXP (x, 0)) == REG)
4112 else if (GET_CODE (XEXP (x, 0)) == MEM)
4114 /* If we have a (addressof (mem ..)), do any instantiation inside
4115 since we know we'll be making the inside valid when we finally
4116 remove the ADDRESSOF. */
4117 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4126 /* Scan all subexpressions. */
4127 fmt = GET_RTX_FORMAT (code);
4128 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4131 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4134 else if (*fmt == 'E')
4135 for (j = 0; j < XVECLEN (x, i); j++)
4136 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4143 /* Optimization: assuming this function does not receive nonlocal gotos,
4144 delete the handlers for such, as well as the insns to establish
4145 and disestablish them. */
4151 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4153 /* Delete the handler by turning off the flag that would
4154 prevent jump_optimize from deleting it.
4155 Also permit deletion of the nonlocal labels themselves
4156 if nothing local refers to them. */
4157 if (GET_CODE (insn) == CODE_LABEL)
4161 LABEL_PRESERVE_P (insn) = 0;
4163 /* Remove it from the nonlocal_label list, to avoid confusing
4165 for (t = nonlocal_labels, last_t = 0; t;
4166 last_t = t, t = TREE_CHAIN (t))
4167 if (DECL_RTL (TREE_VALUE (t)) == insn)
4172 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4174 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4177 if (GET_CODE (insn) == INSN)
4181 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4182 if (reg_mentioned_p (t, PATTERN (insn)))
4188 || (nonlocal_goto_stack_level != 0
4189 && reg_mentioned_p (nonlocal_goto_stack_level,
4191 delete_related_insns (insn);
4199 return max_parm_reg;
4202 /* Return the first insn following those generated by `assign_parms'. */
4205 get_first_nonparm_insn ()
4208 return NEXT_INSN (last_parm_insn);
4209 return get_insns ();
4212 /* Return the first NOTE_INSN_BLOCK_BEG note in the function.
4213 Crash if there is none. */
4216 get_first_block_beg ()
4219 rtx insn = get_first_nonparm_insn ();
4221 for (searcher = insn; searcher; searcher = NEXT_INSN (searcher))
4222 if (GET_CODE (searcher) == NOTE
4223 && NOTE_LINE_NUMBER (searcher) == NOTE_INSN_BLOCK_BEG)
4226 abort (); /* Invalid call to this function. (See comments above.) */
4230 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4231 This means a type for which function calls must pass an address to the
4232 function or get an address back from the function.
4233 EXP may be a type node or an expression (whose type is tested). */
4236 aggregate_value_p (exp)
4239 int i, regno, nregs;
4242 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4244 if (TREE_CODE (type) == VOID_TYPE)
4246 if (RETURN_IN_MEMORY (type))
4248 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4249 and thus can't be returned in registers. */
4250 if (TREE_ADDRESSABLE (type))
4252 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4254 /* Make sure we have suitable call-clobbered regs to return
4255 the value in; if not, we must return it in memory. */
4256 reg = hard_function_value (type, 0, 0);
4258 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4260 if (GET_CODE (reg) != REG)
4263 regno = REGNO (reg);
4264 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4265 for (i = 0; i < nregs; i++)
4266 if (! call_used_regs[regno + i])
4271 /* Assign RTL expressions to the function's parameters.
4272 This may involve copying them into registers and using
4273 those registers as the RTL for them. */
4276 assign_parms (fndecl)
4282 CUMULATIVE_ARGS args_so_far;
4283 enum machine_mode promoted_mode, passed_mode;
4284 enum machine_mode nominal_mode, promoted_nominal_mode;
4286 /* Total space needed so far for args on the stack,
4287 given as a constant and a tree-expression. */
4288 struct args_size stack_args_size;
4289 tree fntype = TREE_TYPE (fndecl);
4290 tree fnargs = DECL_ARGUMENTS (fndecl);
4291 /* This is used for the arg pointer when referring to stack args. */
4292 rtx internal_arg_pointer;
4293 /* This is a dummy PARM_DECL that we used for the function result if
4294 the function returns a structure. */
4295 tree function_result_decl = 0;
4296 #ifdef SETUP_INCOMING_VARARGS
4297 int varargs_setup = 0;
4299 rtx conversion_insns = 0;
4300 struct args_size alignment_pad;
4302 /* Nonzero if the last arg is named `__builtin_va_alist',
4303 which is used on some machines for old-fashioned non-ANSI varargs.h;
4304 this should be stuck onto the stack as if it had arrived there. */
4306 = (current_function_varargs
4308 && (parm = tree_last (fnargs)) != 0
4310 && (! strcmp (IDENTIFIER_POINTER (DECL_NAME (parm)),
4311 "__builtin_va_alist")));
4313 /* Nonzero if function takes extra anonymous args.
4314 This means the last named arg must be on the stack
4315 right before the anonymous ones. */
4317 = (TYPE_ARG_TYPES (fntype) != 0
4318 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4319 != void_type_node));
4321 current_function_stdarg = stdarg;
4323 /* If the reg that the virtual arg pointer will be translated into is
4324 not a fixed reg or is the stack pointer, make a copy of the virtual
4325 arg pointer, and address parms via the copy. The frame pointer is
4326 considered fixed even though it is not marked as such.
4328 The second time through, simply use ap to avoid generating rtx. */
4330 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4331 || ! (fixed_regs[ARG_POINTER_REGNUM]
4332 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4333 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4335 internal_arg_pointer = virtual_incoming_args_rtx;
4336 current_function_internal_arg_pointer = internal_arg_pointer;
4338 stack_args_size.constant = 0;
4339 stack_args_size.var = 0;
4341 /* If struct value address is treated as the first argument, make it so. */
4342 if (aggregate_value_p (DECL_RESULT (fndecl))
4343 && ! current_function_returns_pcc_struct
4344 && struct_value_incoming_rtx == 0)
4346 tree type = build_pointer_type (TREE_TYPE (fntype));
4348 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4350 DECL_ARG_TYPE (function_result_decl) = type;
4351 TREE_CHAIN (function_result_decl) = fnargs;
4352 fnargs = function_result_decl;
4355 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4356 parm_reg_stack_loc = (rtx *) xcalloc (max_parm_reg, sizeof (rtx));
4358 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4359 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4361 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
4364 /* We haven't yet found an argument that we must push and pretend the
4366 current_function_pretend_args_size = 0;
4368 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4370 struct args_size stack_offset;
4371 struct args_size arg_size;
4372 int passed_pointer = 0;
4373 int did_conversion = 0;
4374 tree passed_type = DECL_ARG_TYPE (parm);
4375 tree nominal_type = TREE_TYPE (parm);
4377 int last_named = 0, named_arg;
4379 /* Set LAST_NAMED if this is last named arg before last
4381 if (stdarg || current_function_varargs)
4385 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4386 if (DECL_NAME (tem))
4392 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4393 most machines, if this is a varargs/stdarg function, then we treat
4394 the last named arg as if it were anonymous too. */
4395 named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4397 if (TREE_TYPE (parm) == error_mark_node
4398 /* This can happen after weird syntax errors
4399 or if an enum type is defined among the parms. */
4400 || TREE_CODE (parm) != PARM_DECL
4401 || passed_type == NULL)
4403 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4404 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4405 TREE_USED (parm) = 1;
4409 /* For varargs.h function, save info about regs and stack space
4410 used by the individual args, not including the va_alist arg. */
4411 if (hide_last_arg && last_named)
4412 current_function_args_info = args_so_far;
4414 /* Find mode of arg as it is passed, and mode of arg
4415 as it should be during execution of this function. */
4416 passed_mode = TYPE_MODE (passed_type);
4417 nominal_mode = TYPE_MODE (nominal_type);
4419 /* If the parm's mode is VOID, its value doesn't matter,
4420 and avoid the usual things like emit_move_insn that could crash. */
4421 if (nominal_mode == VOIDmode)
4423 SET_DECL_RTL (parm, const0_rtx);
4424 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4428 /* If the parm is to be passed as a transparent union, use the
4429 type of the first field for the tests below. We have already
4430 verified that the modes are the same. */
4431 if (DECL_TRANSPARENT_UNION (parm)
4432 || (TREE_CODE (passed_type) == UNION_TYPE
4433 && TYPE_TRANSPARENT_UNION (passed_type)))
4434 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4436 /* See if this arg was passed by invisible reference. It is if
4437 it is an object whose size depends on the contents of the
4438 object itself or if the machine requires these objects be passed
4441 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4442 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4443 || TREE_ADDRESSABLE (passed_type)
4444 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4445 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4446 passed_type, named_arg)
4450 passed_type = nominal_type = build_pointer_type (passed_type);
4452 passed_mode = nominal_mode = Pmode;
4455 promoted_mode = passed_mode;
4457 #ifdef PROMOTE_FUNCTION_ARGS
4458 /* Compute the mode in which the arg is actually extended to. */
4459 unsignedp = TREE_UNSIGNED (passed_type);
4460 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4463 /* Let machine desc say which reg (if any) the parm arrives in.
4464 0 means it arrives on the stack. */
4465 #ifdef FUNCTION_INCOMING_ARG
4466 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4467 passed_type, named_arg);
4469 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4470 passed_type, named_arg);
4473 if (entry_parm == 0)
4474 promoted_mode = passed_mode;
4476 #ifdef SETUP_INCOMING_VARARGS
4477 /* If this is the last named parameter, do any required setup for
4478 varargs or stdargs. We need to know about the case of this being an
4479 addressable type, in which case we skip the registers it
4480 would have arrived in.
4482 For stdargs, LAST_NAMED will be set for two parameters, the one that
4483 is actually the last named, and the dummy parameter. We only
4484 want to do this action once.
4486 Also, indicate when RTL generation is to be suppressed. */
4487 if (last_named && !varargs_setup)
4489 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4490 current_function_pretend_args_size, 0);
4495 /* Determine parm's home in the stack,
4496 in case it arrives in the stack or we should pretend it did.
4498 Compute the stack position and rtx where the argument arrives
4501 There is one complexity here: If this was a parameter that would
4502 have been passed in registers, but wasn't only because it is
4503 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4504 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4505 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4506 0 as it was the previous time. */
4508 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4509 locate_and_pad_parm (promoted_mode, passed_type,
4510 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4513 #ifdef FUNCTION_INCOMING_ARG
4514 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4516 pretend_named) != 0,
4518 FUNCTION_ARG (args_so_far, promoted_mode,
4520 pretend_named) != 0,
4523 fndecl, &stack_args_size, &stack_offset, &arg_size,
4527 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4529 if (offset_rtx == const0_rtx)
4530 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4532 stack_parm = gen_rtx_MEM (promoted_mode,
4533 gen_rtx_PLUS (Pmode,
4534 internal_arg_pointer,
4537 set_mem_attributes (stack_parm, parm, 1);
4540 /* If this parameter was passed both in registers and in the stack,
4541 use the copy on the stack. */
4542 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4545 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4546 /* If this parm was passed part in regs and part in memory,
4547 pretend it arrived entirely in memory
4548 by pushing the register-part onto the stack.
4550 In the special case of a DImode or DFmode that is split,
4551 we could put it together in a pseudoreg directly,
4552 but for now that's not worth bothering with. */
4556 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4557 passed_type, named_arg);
4561 current_function_pretend_args_size
4562 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4563 / (PARM_BOUNDARY / BITS_PER_UNIT)
4564 * (PARM_BOUNDARY / BITS_PER_UNIT));
4566 /* Handle calls that pass values in multiple non-contiguous
4567 locations. The Irix 6 ABI has examples of this. */
4568 if (GET_CODE (entry_parm) == PARALLEL)
4569 emit_group_store (validize_mem (stack_parm), entry_parm,
4570 int_size_in_bytes (TREE_TYPE (parm)));
4573 move_block_from_reg (REGNO (entry_parm),
4574 validize_mem (stack_parm), nregs,
4575 int_size_in_bytes (TREE_TYPE (parm)));
4577 entry_parm = stack_parm;
4582 /* If we didn't decide this parm came in a register,
4583 by default it came on the stack. */
4584 if (entry_parm == 0)
4585 entry_parm = stack_parm;
4587 /* Record permanently how this parm was passed. */
4588 DECL_INCOMING_RTL (parm) = entry_parm;
4590 /* If there is actually space on the stack for this parm,
4591 count it in stack_args_size; otherwise set stack_parm to 0
4592 to indicate there is no preallocated stack slot for the parm. */
4594 if (entry_parm == stack_parm
4595 || (GET_CODE (entry_parm) == PARALLEL
4596 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4597 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4598 /* On some machines, even if a parm value arrives in a register
4599 there is still an (uninitialized) stack slot allocated for it.
4601 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4602 whether this parameter already has a stack slot allocated,
4603 because an arg block exists only if current_function_args_size
4604 is larger than some threshold, and we haven't calculated that
4605 yet. So, for now, we just assume that stack slots never exist
4607 || REG_PARM_STACK_SPACE (fndecl) > 0
4611 stack_args_size.constant += arg_size.constant;
4613 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4616 /* No stack slot was pushed for this parm. */
4619 /* Update info on where next arg arrives in registers. */
4621 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4622 passed_type, named_arg);
4624 /* If we can't trust the parm stack slot to be aligned enough
4625 for its ultimate type, don't use that slot after entry.
4626 We'll make another stack slot, if we need one. */
4628 unsigned int thisparm_boundary
4629 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4631 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4635 /* If parm was passed in memory, and we need to convert it on entry,
4636 don't store it back in that same slot. */
4638 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4641 /* When an argument is passed in multiple locations, we can't
4642 make use of this information, but we can save some copying if
4643 the whole argument is passed in a single register. */
4644 if (GET_CODE (entry_parm) == PARALLEL
4645 && nominal_mode != BLKmode && passed_mode != BLKmode)
4647 int i, len = XVECLEN (entry_parm, 0);
4649 for (i = 0; i < len; i++)
4650 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4651 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4652 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4654 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4656 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4657 DECL_INCOMING_RTL (parm) = entry_parm;
4662 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4663 in the mode in which it arrives.
4664 STACK_PARM is an RTX for a stack slot where the parameter can live
4665 during the function (in case we want to put it there).
4666 STACK_PARM is 0 if no stack slot was pushed for it.
4668 Now output code if necessary to convert ENTRY_PARM to
4669 the type in which this function declares it,
4670 and store that result in an appropriate place,
4671 which may be a pseudo reg, may be STACK_PARM,
4672 or may be a local stack slot if STACK_PARM is 0.
4674 Set DECL_RTL to that place. */
4676 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4678 /* If a BLKmode arrives in registers, copy it to a stack slot.
4679 Handle calls that pass values in multiple non-contiguous
4680 locations. The Irix 6 ABI has examples of this. */
4681 if (GET_CODE (entry_parm) == REG
4682 || GET_CODE (entry_parm) == PARALLEL)
4685 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4688 /* Note that we will be storing an integral number of words.
4689 So we have to be careful to ensure that we allocate an
4690 integral number of words. We do this below in the
4691 assign_stack_local if space was not allocated in the argument
4692 list. If it was, this will not work if PARM_BOUNDARY is not
4693 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4694 if it becomes a problem. */
4696 if (stack_parm == 0)
4699 = assign_stack_local (GET_MODE (entry_parm),
4701 set_mem_attributes (stack_parm, parm, 1);
4704 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4707 /* Handle calls that pass values in multiple non-contiguous
4708 locations. The Irix 6 ABI has examples of this. */
4709 if (GET_CODE (entry_parm) == PARALLEL)
4710 emit_group_store (validize_mem (stack_parm), entry_parm,
4711 int_size_in_bytes (TREE_TYPE (parm)));
4713 move_block_from_reg (REGNO (entry_parm),
4714 validize_mem (stack_parm),
4715 size_stored / UNITS_PER_WORD,
4716 int_size_in_bytes (TREE_TYPE (parm)));
4718 SET_DECL_RTL (parm, stack_parm);
4720 else if (! ((! optimize
4721 && ! DECL_REGISTER (parm))
4722 || TREE_SIDE_EFFECTS (parm)
4723 /* If -ffloat-store specified, don't put explicit
4724 float variables into registers. */
4725 || (flag_float_store
4726 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4727 /* Always assign pseudo to structure return or item passed
4728 by invisible reference. */
4729 || passed_pointer || parm == function_result_decl)
4731 /* Store the parm in a pseudoregister during the function, but we
4732 may need to do it in a wider mode. */
4735 unsigned int regno, regnoi = 0, regnor = 0;
4737 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4739 promoted_nominal_mode
4740 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4742 parmreg = gen_reg_rtx (promoted_nominal_mode);
4743 mark_user_reg (parmreg);
4745 /* If this was an item that we received a pointer to, set DECL_RTL
4749 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4751 set_mem_attributes (x, parm, 1);
4752 SET_DECL_RTL (parm, x);
4756 SET_DECL_RTL (parm, parmreg);
4757 maybe_set_unchanging (DECL_RTL (parm), parm);
4760 /* Copy the value into the register. */
4761 if (nominal_mode != passed_mode
4762 || promoted_nominal_mode != promoted_mode)
4765 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4766 mode, by the caller. We now have to convert it to
4767 NOMINAL_MODE, if different. However, PARMREG may be in
4768 a different mode than NOMINAL_MODE if it is being stored
4771 If ENTRY_PARM is a hard register, it might be in a register
4772 not valid for operating in its mode (e.g., an odd-numbered
4773 register for a DFmode). In that case, moves are the only
4774 thing valid, so we can't do a convert from there. This
4775 occurs when the calling sequence allow such misaligned
4778 In addition, the conversion may involve a call, which could
4779 clobber parameters which haven't been copied to pseudo
4780 registers yet. Therefore, we must first copy the parm to
4781 a pseudo reg here, and save the conversion until after all
4782 parameters have been moved. */
4784 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4786 emit_move_insn (tempreg, validize_mem (entry_parm));
4788 push_to_sequence (conversion_insns);
4789 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4791 if (GET_CODE (tempreg) == SUBREG
4792 && GET_MODE (tempreg) == nominal_mode
4793 && GET_CODE (SUBREG_REG (tempreg)) == REG
4794 && nominal_mode == passed_mode
4795 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4796 && GET_MODE_SIZE (GET_MODE (tempreg))
4797 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4799 /* The argument is already sign/zero extended, so note it
4801 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4802 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4805 /* TREE_USED gets set erroneously during expand_assignment. */
4806 save_tree_used = TREE_USED (parm);
4807 expand_assignment (parm,
4808 make_tree (nominal_type, tempreg), 0, 0);
4809 TREE_USED (parm) = save_tree_used;
4810 conversion_insns = get_insns ();
4815 emit_move_insn (parmreg, validize_mem (entry_parm));
4817 /* If we were passed a pointer but the actual value
4818 can safely live in a register, put it in one. */
4819 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4820 /* If by-reference argument was promoted, demote it. */
4821 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4823 && ! DECL_REGISTER (parm))
4824 || TREE_SIDE_EFFECTS (parm)
4825 /* If -ffloat-store specified, don't put explicit
4826 float variables into registers. */
4827 || (flag_float_store
4828 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4830 /* We can't use nominal_mode, because it will have been set to
4831 Pmode above. We must use the actual mode of the parm. */
4832 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4833 mark_user_reg (parmreg);
4834 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4836 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4837 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4838 push_to_sequence (conversion_insns);
4839 emit_move_insn (tempreg, DECL_RTL (parm));
4841 convert_to_mode (GET_MODE (parmreg),
4844 emit_move_insn (parmreg, DECL_RTL (parm));
4845 conversion_insns = get_insns();
4850 emit_move_insn (parmreg, DECL_RTL (parm));
4851 SET_DECL_RTL (parm, parmreg);
4852 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4856 #ifdef FUNCTION_ARG_CALLEE_COPIES
4857 /* If we are passed an arg by reference and it is our responsibility
4858 to make a copy, do it now.
4859 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4860 original argument, so we must recreate them in the call to
4861 FUNCTION_ARG_CALLEE_COPIES. */
4862 /* ??? Later add code to handle the case that if the argument isn't
4863 modified, don't do the copy. */
4865 else if (passed_pointer
4866 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4867 TYPE_MODE (DECL_ARG_TYPE (parm)),
4868 DECL_ARG_TYPE (parm),
4870 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4873 tree type = DECL_ARG_TYPE (parm);
4875 /* This sequence may involve a library call perhaps clobbering
4876 registers that haven't been copied to pseudos yet. */
4878 push_to_sequence (conversion_insns);
4880 if (!COMPLETE_TYPE_P (type)
4881 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4882 /* This is a variable sized object. */
4883 copy = gen_rtx_MEM (BLKmode,
4884 allocate_dynamic_stack_space
4885 (expr_size (parm), NULL_RTX,
4886 TYPE_ALIGN (type)));
4888 copy = assign_stack_temp (TYPE_MODE (type),
4889 int_size_in_bytes (type), 1);
4890 set_mem_attributes (copy, parm, 1);
4892 store_expr (parm, copy, 0);
4893 emit_move_insn (parmreg, XEXP (copy, 0));
4894 conversion_insns = get_insns ();
4898 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4900 /* In any case, record the parm's desired stack location
4901 in case we later discover it must live in the stack.
4903 If it is a COMPLEX value, store the stack location for both
4906 if (GET_CODE (parmreg) == CONCAT)
4907 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4909 regno = REGNO (parmreg);
4911 if (regno >= max_parm_reg)
4914 int old_max_parm_reg = max_parm_reg;
4916 /* It's slow to expand this one register at a time,
4917 but it's also rare and we need max_parm_reg to be
4918 precisely correct. */
4919 max_parm_reg = regno + 1;
4920 new = (rtx *) xrealloc (parm_reg_stack_loc,
4921 max_parm_reg * sizeof (rtx));
4922 memset ((char *) (new + old_max_parm_reg), 0,
4923 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4924 parm_reg_stack_loc = new;
4927 if (GET_CODE (parmreg) == CONCAT)
4929 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4931 regnor = REGNO (gen_realpart (submode, parmreg));
4932 regnoi = REGNO (gen_imagpart (submode, parmreg));
4934 if (stack_parm != 0)
4936 parm_reg_stack_loc[regnor]
4937 = gen_realpart (submode, stack_parm);
4938 parm_reg_stack_loc[regnoi]
4939 = gen_imagpart (submode, stack_parm);
4943 parm_reg_stack_loc[regnor] = 0;
4944 parm_reg_stack_loc[regnoi] = 0;
4948 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4950 /* Mark the register as eliminable if we did no conversion
4951 and it was copied from memory at a fixed offset,
4952 and the arg pointer was not copied to a pseudo-reg.
4953 If the arg pointer is a pseudo reg or the offset formed
4954 an invalid address, such memory-equivalences
4955 as we make here would screw up life analysis for it. */
4956 if (nominal_mode == passed_mode
4959 && GET_CODE (stack_parm) == MEM
4960 && stack_offset.var == 0
4961 && reg_mentioned_p (virtual_incoming_args_rtx,
4962 XEXP (stack_parm, 0)))
4964 rtx linsn = get_last_insn ();
4967 /* Mark complex types separately. */
4968 if (GET_CODE (parmreg) == CONCAT)
4969 /* Scan backwards for the set of the real and
4971 for (sinsn = linsn; sinsn != 0;
4972 sinsn = prev_nonnote_insn (sinsn))
4974 set = single_set (sinsn);
4976 && SET_DEST (set) == regno_reg_rtx [regnoi])
4978 = gen_rtx_EXPR_LIST (REG_EQUIV,
4979 parm_reg_stack_loc[regnoi],
4982 && SET_DEST (set) == regno_reg_rtx [regnor])
4984 = gen_rtx_EXPR_LIST (REG_EQUIV,
4985 parm_reg_stack_loc[regnor],
4988 else if ((set = single_set (linsn)) != 0
4989 && SET_DEST (set) == parmreg)
4991 = gen_rtx_EXPR_LIST (REG_EQUIV,
4992 stack_parm, REG_NOTES (linsn));
4995 /* For pointer data type, suggest pointer register. */
4996 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4997 mark_reg_pointer (parmreg,
4998 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5000 /* If something wants our address, try to use ADDRESSOF. */
5001 if (TREE_ADDRESSABLE (parm))
5003 /* If we end up putting something into the stack,
5004 fixup_var_refs_insns will need to make a pass over
5005 all the instructions. It looks through the pending
5006 sequences -- but it can't see the ones in the
5007 CONVERSION_INSNS, if they're not on the sequence
5008 stack. So, we go back to that sequence, just so that
5009 the fixups will happen. */
5010 push_to_sequence (conversion_insns);
5011 put_var_into_stack (parm);
5012 conversion_insns = get_insns ();
5018 /* Value must be stored in the stack slot STACK_PARM
5019 during function execution. */
5021 if (promoted_mode != nominal_mode)
5023 /* Conversion is required. */
5024 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
5026 emit_move_insn (tempreg, validize_mem (entry_parm));
5028 push_to_sequence (conversion_insns);
5029 entry_parm = convert_to_mode (nominal_mode, tempreg,
5030 TREE_UNSIGNED (TREE_TYPE (parm)));
5032 /* ??? This may need a big-endian conversion on sparc64. */
5033 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
5035 conversion_insns = get_insns ();
5040 if (entry_parm != stack_parm)
5042 if (stack_parm == 0)
5045 = assign_stack_local (GET_MODE (entry_parm),
5046 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
5047 set_mem_attributes (stack_parm, parm, 1);
5050 if (promoted_mode != nominal_mode)
5052 push_to_sequence (conversion_insns);
5053 emit_move_insn (validize_mem (stack_parm),
5054 validize_mem (entry_parm));
5055 conversion_insns = get_insns ();
5059 emit_move_insn (validize_mem (stack_parm),
5060 validize_mem (entry_parm));
5063 SET_DECL_RTL (parm, stack_parm);
5066 /* If this "parameter" was the place where we are receiving the
5067 function's incoming structure pointer, set up the result. */
5068 if (parm == function_result_decl)
5070 tree result = DECL_RESULT (fndecl);
5071 rtx addr = DECL_RTL (parm);
5074 #ifdef POINTERS_EXTEND_UNSIGNED
5075 if (GET_MODE (addr) != Pmode)
5076 addr = convert_memory_address (Pmode, addr);
5079 x = gen_rtx_MEM (DECL_MODE (result), addr);
5080 set_mem_attributes (x, result, 1);
5081 SET_DECL_RTL (result, x);
5084 if (GET_CODE (DECL_RTL (parm)) == REG)
5085 REGNO_DECL (REGNO (DECL_RTL (parm))) = parm;
5086 else if (GET_CODE (DECL_RTL (parm)) == CONCAT)
5088 REGNO_DECL (REGNO (XEXP (DECL_RTL (parm), 0))) = parm;
5089 REGNO_DECL (REGNO (XEXP (DECL_RTL (parm), 1))) = parm;
5094 /* Output all parameter conversion instructions (possibly including calls)
5095 now that all parameters have been copied out of hard registers. */
5096 emit_insns (conversion_insns);
5098 last_parm_insn = get_last_insn ();
5100 current_function_args_size = stack_args_size.constant;
5102 /* Adjust function incoming argument size for alignment and
5105 #ifdef REG_PARM_STACK_SPACE
5106 #ifndef MAYBE_REG_PARM_STACK_SPACE
5107 current_function_args_size = MAX (current_function_args_size,
5108 REG_PARM_STACK_SPACE (fndecl));
5112 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
5114 current_function_args_size
5115 = ((current_function_args_size + STACK_BYTES - 1)
5116 / STACK_BYTES) * STACK_BYTES;
5118 #ifdef ARGS_GROW_DOWNWARD
5119 current_function_arg_offset_rtx
5120 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5121 : expand_expr (size_diffop (stack_args_size.var,
5122 size_int (-stack_args_size.constant)),
5123 NULL_RTX, VOIDmode, 0));
5125 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5128 /* See how many bytes, if any, of its args a function should try to pop
5131 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5132 current_function_args_size);
5134 /* For stdarg.h function, save info about
5135 regs and stack space used by the named args. */
5138 current_function_args_info = args_so_far;
5140 /* Set the rtx used for the function return value. Put this in its
5141 own variable so any optimizers that need this information don't have
5142 to include tree.h. Do this here so it gets done when an inlined
5143 function gets output. */
5145 current_function_return_rtx
5146 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5147 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5149 /* If scalar return value was computed in a pseudo-reg, or was a named
5150 return value that got dumped to the stack, copy that to the hard
5152 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5154 tree decl_result = DECL_RESULT (fndecl);
5155 rtx decl_rtl = DECL_RTL (decl_result);
5157 if (REG_P (decl_rtl)
5158 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5159 : DECL_REGISTER (decl_result))
5163 #ifdef FUNCTION_OUTGOING_VALUE
5164 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5167 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5170 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5171 /* The delay slot scheduler assumes that current_function_return_rtx
5172 holds the hard register containing the return value, not a
5173 temporary pseudo. */
5174 current_function_return_rtx = real_decl_rtl;
5179 /* Indicate whether REGNO is an incoming argument to the current function
5180 that was promoted to a wider mode. If so, return the RTX for the
5181 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5182 that REGNO is promoted from and whether the promotion was signed or
5185 #ifdef PROMOTE_FUNCTION_ARGS
5188 promoted_input_arg (regno, pmode, punsignedp)
5190 enum machine_mode *pmode;
5195 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5196 arg = TREE_CHAIN (arg))
5197 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5198 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5199 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5201 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5202 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5204 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5205 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5206 && mode != DECL_MODE (arg))
5208 *pmode = DECL_MODE (arg);
5209 *punsignedp = unsignedp;
5210 return DECL_INCOMING_RTL (arg);
5219 /* Compute the size and offset from the start of the stacked arguments for a
5220 parm passed in mode PASSED_MODE and with type TYPE.
5222 INITIAL_OFFSET_PTR points to the current offset into the stacked
5225 The starting offset and size for this parm are returned in *OFFSET_PTR
5226 and *ARG_SIZE_PTR, respectively.
5228 IN_REGS is non-zero if the argument will be passed in registers. It will
5229 never be set if REG_PARM_STACK_SPACE is not defined.
5231 FNDECL is the function in which the argument was defined.
5233 There are two types of rounding that are done. The first, controlled by
5234 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5235 list to be aligned to the specific boundary (in bits). This rounding
5236 affects the initial and starting offsets, but not the argument size.
5238 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5239 optionally rounds the size of the parm to PARM_BOUNDARY. The
5240 initial offset is not affected by this rounding, while the size always
5241 is and the starting offset may be. */
5243 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
5244 initial_offset_ptr is positive because locate_and_pad_parm's
5245 callers pass in the total size of args so far as
5246 initial_offset_ptr. arg_size_ptr is always positive. */
5249 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
5250 initial_offset_ptr, offset_ptr, arg_size_ptr,
5252 enum machine_mode passed_mode;
5254 int in_regs ATTRIBUTE_UNUSED;
5255 tree fndecl ATTRIBUTE_UNUSED;
5256 struct args_size *initial_offset_ptr;
5257 struct args_size *offset_ptr;
5258 struct args_size *arg_size_ptr;
5259 struct args_size *alignment_pad;
5263 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5264 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5265 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5267 #ifdef REG_PARM_STACK_SPACE
5268 /* If we have found a stack parm before we reach the end of the
5269 area reserved for registers, skip that area. */
5272 int reg_parm_stack_space = 0;
5274 #ifdef MAYBE_REG_PARM_STACK_SPACE
5275 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5277 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5279 if (reg_parm_stack_space > 0)
5281 if (initial_offset_ptr->var)
5283 initial_offset_ptr->var
5284 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5285 ssize_int (reg_parm_stack_space));
5286 initial_offset_ptr->constant = 0;
5288 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5289 initial_offset_ptr->constant = reg_parm_stack_space;
5292 #endif /* REG_PARM_STACK_SPACE */
5294 arg_size_ptr->var = 0;
5295 arg_size_ptr->constant = 0;
5296 alignment_pad->var = 0;
5297 alignment_pad->constant = 0;
5299 #ifdef ARGS_GROW_DOWNWARD
5300 if (initial_offset_ptr->var)
5302 offset_ptr->constant = 0;
5303 offset_ptr->var = size_binop (MINUS_EXPR, ssize_int (0),
5304 initial_offset_ptr->var);
5308 offset_ptr->constant = -initial_offset_ptr->constant;
5309 offset_ptr->var = 0;
5311 if (where_pad != none
5312 && (!host_integerp (sizetree, 1)
5313 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5314 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5315 SUB_PARM_SIZE (*offset_ptr, sizetree);
5316 if (where_pad != downward)
5317 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5318 if (initial_offset_ptr->var)
5319 arg_size_ptr->var = size_binop (MINUS_EXPR,
5320 size_binop (MINUS_EXPR,
5322 initial_offset_ptr->var),
5326 arg_size_ptr->constant = (-initial_offset_ptr->constant
5327 - offset_ptr->constant);
5329 #else /* !ARGS_GROW_DOWNWARD */
5331 #ifdef REG_PARM_STACK_SPACE
5332 || REG_PARM_STACK_SPACE (fndecl) > 0
5335 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5336 *offset_ptr = *initial_offset_ptr;
5338 #ifdef PUSH_ROUNDING
5339 if (passed_mode != BLKmode)
5340 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5343 /* Pad_below needs the pre-rounded size to know how much to pad below
5344 so this must be done before rounding up. */
5345 if (where_pad == downward
5346 /* However, BLKmode args passed in regs have their padding done elsewhere.
5347 The stack slot must be able to hold the entire register. */
5348 && !(in_regs && passed_mode == BLKmode))
5349 pad_below (offset_ptr, passed_mode, sizetree);
5351 if (where_pad != none
5352 && (!host_integerp (sizetree, 1)
5353 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5354 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5356 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5357 #endif /* ARGS_GROW_DOWNWARD */
5360 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5361 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5364 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5365 struct args_size *offset_ptr;
5367 struct args_size *alignment_pad;
5369 tree save_var = NULL_TREE;
5370 HOST_WIDE_INT save_constant = 0;
5372 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5374 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5376 save_var = offset_ptr->var;
5377 save_constant = offset_ptr->constant;
5380 alignment_pad->var = NULL_TREE;
5381 alignment_pad->constant = 0;
5383 if (boundary > BITS_PER_UNIT)
5385 if (offset_ptr->var)
5388 #ifdef ARGS_GROW_DOWNWARD
5393 (ARGS_SIZE_TREE (*offset_ptr),
5394 boundary / BITS_PER_UNIT);
5395 offset_ptr->constant = 0; /*?*/
5396 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5397 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5402 offset_ptr->constant =
5403 #ifdef ARGS_GROW_DOWNWARD
5404 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5406 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5408 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5409 alignment_pad->constant = offset_ptr->constant - save_constant;
5414 #ifndef ARGS_GROW_DOWNWARD
5416 pad_below (offset_ptr, passed_mode, sizetree)
5417 struct args_size *offset_ptr;
5418 enum machine_mode passed_mode;
5421 if (passed_mode != BLKmode)
5423 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5424 offset_ptr->constant
5425 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5426 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5427 - GET_MODE_SIZE (passed_mode));
5431 if (TREE_CODE (sizetree) != INTEGER_CST
5432 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5434 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5435 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5437 ADD_PARM_SIZE (*offset_ptr, s2);
5438 SUB_PARM_SIZE (*offset_ptr, sizetree);
5444 /* Walk the tree of blocks describing the binding levels within a function
5445 and warn about uninitialized variables.
5446 This is done after calling flow_analysis and before global_alloc
5447 clobbers the pseudo-regs to hard regs. */
5450 uninitialized_vars_warning (block)
5454 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5456 if (warn_uninitialized
5457 && TREE_CODE (decl) == VAR_DECL
5458 /* These warnings are unreliable for and aggregates
5459 because assigning the fields one by one can fail to convince
5460 flow.c that the entire aggregate was initialized.
5461 Unions are troublesome because members may be shorter. */
5462 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5463 && DECL_RTL (decl) != 0
5464 && GET_CODE (DECL_RTL (decl)) == REG
5465 /* Global optimizations can make it difficult to determine if a
5466 particular variable has been initialized. However, a VAR_DECL
5467 with a nonzero DECL_INITIAL had an initializer, so do not
5468 claim it is potentially uninitialized.
5470 We do not care about the actual value in DECL_INITIAL, so we do
5471 not worry that it may be a dangling pointer. */
5472 && DECL_INITIAL (decl) == NULL_TREE
5473 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5474 warning_with_decl (decl,
5475 "`%s' might be used uninitialized in this function");
5477 && TREE_CODE (decl) == VAR_DECL
5478 && DECL_RTL (decl) != 0
5479 && GET_CODE (DECL_RTL (decl)) == REG
5480 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5481 warning_with_decl (decl,
5482 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5484 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5485 uninitialized_vars_warning (sub);
5488 /* Do the appropriate part of uninitialized_vars_warning
5489 but for arguments instead of local variables. */
5492 setjmp_args_warning ()
5495 for (decl = DECL_ARGUMENTS (current_function_decl);
5496 decl; decl = TREE_CHAIN (decl))
5497 if (DECL_RTL (decl) != 0
5498 && GET_CODE (DECL_RTL (decl)) == REG
5499 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5500 warning_with_decl (decl,
5501 "argument `%s' might be clobbered by `longjmp' or `vfork'");
5504 /* If this function call setjmp, put all vars into the stack
5505 unless they were declared `register'. */
5508 setjmp_protect (block)
5512 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5513 if ((TREE_CODE (decl) == VAR_DECL
5514 || TREE_CODE (decl) == PARM_DECL)
5515 && DECL_RTL (decl) != 0
5516 && (GET_CODE (DECL_RTL (decl)) == REG
5517 || (GET_CODE (DECL_RTL (decl)) == MEM
5518 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5519 /* If this variable came from an inline function, it must be
5520 that its life doesn't overlap the setjmp. If there was a
5521 setjmp in the function, it would already be in memory. We
5522 must exclude such variable because their DECL_RTL might be
5523 set to strange things such as virtual_stack_vars_rtx. */
5524 && ! DECL_FROM_INLINE (decl)
5526 #ifdef NON_SAVING_SETJMP
5527 /* If longjmp doesn't restore the registers,
5528 don't put anything in them. */
5532 ! DECL_REGISTER (decl)))
5533 put_var_into_stack (decl);
5534 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5535 setjmp_protect (sub);
5538 /* Like the previous function, but for args instead of local variables. */
5541 setjmp_protect_args ()
5544 for (decl = DECL_ARGUMENTS (current_function_decl);
5545 decl; decl = TREE_CHAIN (decl))
5546 if ((TREE_CODE (decl) == VAR_DECL
5547 || TREE_CODE (decl) == PARM_DECL)
5548 && DECL_RTL (decl) != 0
5549 && (GET_CODE (DECL_RTL (decl)) == REG
5550 || (GET_CODE (DECL_RTL (decl)) == MEM
5551 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5553 /* If longjmp doesn't restore the registers,
5554 don't put anything in them. */
5555 #ifdef NON_SAVING_SETJMP
5559 ! DECL_REGISTER (decl)))
5560 put_var_into_stack (decl);
5563 /* Return the context-pointer register corresponding to DECL,
5564 or 0 if it does not need one. */
5567 lookup_static_chain (decl)
5570 tree context = decl_function_context (decl);
5574 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5577 /* We treat inline_function_decl as an alias for the current function
5578 because that is the inline function whose vars, types, etc.
5579 are being merged into the current function.
5580 See expand_inline_function. */
5581 if (context == current_function_decl || context == inline_function_decl)
5582 return virtual_stack_vars_rtx;
5584 for (link = context_display; link; link = TREE_CHAIN (link))
5585 if (TREE_PURPOSE (link) == context)
5586 return RTL_EXPR_RTL (TREE_VALUE (link));
5591 /* Convert a stack slot address ADDR for variable VAR
5592 (from a containing function)
5593 into an address valid in this function (using a static chain). */
5596 fix_lexical_addr (addr, var)
5601 HOST_WIDE_INT displacement;
5602 tree context = decl_function_context (var);
5603 struct function *fp;
5606 /* If this is the present function, we need not do anything. */
5607 if (context == current_function_decl || context == inline_function_decl)
5610 fp = find_function_data (context);
5612 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5613 addr = XEXP (XEXP (addr, 0), 0);
5615 /* Decode given address as base reg plus displacement. */
5616 if (GET_CODE (addr) == REG)
5617 basereg = addr, displacement = 0;
5618 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5619 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5623 /* We accept vars reached via the containing function's
5624 incoming arg pointer and via its stack variables pointer. */
5625 if (basereg == fp->internal_arg_pointer)
5627 /* If reached via arg pointer, get the arg pointer value
5628 out of that function's stack frame.
5630 There are two cases: If a separate ap is needed, allocate a
5631 slot in the outer function for it and dereference it that way.
5632 This is correct even if the real ap is actually a pseudo.
5633 Otherwise, just adjust the offset from the frame pointer to
5636 #ifdef NEED_SEPARATE_AP
5639 addr = get_arg_pointer_save_area (fp);
5640 addr = fix_lexical_addr (XEXP (addr, 0), var);
5641 addr = memory_address (Pmode, addr);
5643 base = gen_rtx_MEM (Pmode, addr);
5644 set_mem_alias_set (base, get_frame_alias_set ());
5645 base = copy_to_reg (base);
5647 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5648 base = lookup_static_chain (var);
5652 else if (basereg == virtual_stack_vars_rtx)
5654 /* This is the same code as lookup_static_chain, duplicated here to
5655 avoid an extra call to decl_function_context. */
5658 for (link = context_display; link; link = TREE_CHAIN (link))
5659 if (TREE_PURPOSE (link) == context)
5661 base = RTL_EXPR_RTL (TREE_VALUE (link));
5669 /* Use same offset, relative to appropriate static chain or argument
5671 return plus_constant (base, displacement);
5674 /* Return the address of the trampoline for entering nested fn FUNCTION.
5675 If necessary, allocate a trampoline (in the stack frame)
5676 and emit rtl to initialize its contents (at entry to this function). */
5679 trampoline_address (function)
5685 struct function *fp;
5688 /* Find an existing trampoline and return it. */
5689 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5690 if (TREE_PURPOSE (link) == function)
5692 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5694 for (fp = outer_function_chain; fp; fp = fp->outer)
5695 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5696 if (TREE_PURPOSE (link) == function)
5698 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5700 return adjust_trampoline_addr (tramp);
5703 /* None exists; we must make one. */
5705 /* Find the `struct function' for the function containing FUNCTION. */
5707 fn_context = decl_function_context (function);
5708 if (fn_context != current_function_decl
5709 && fn_context != inline_function_decl)
5710 fp = find_function_data (fn_context);
5712 /* Allocate run-time space for this trampoline
5713 (usually in the defining function's stack frame). */
5714 #ifdef ALLOCATE_TRAMPOLINE
5715 tramp = ALLOCATE_TRAMPOLINE (fp);
5717 /* If rounding needed, allocate extra space
5718 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5719 #ifdef TRAMPOLINE_ALIGNMENT
5720 #define TRAMPOLINE_REAL_SIZE \
5721 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5723 #define TRAMPOLINE_REAL_SIZE (TRAMPOLINE_SIZE)
5725 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5729 /* Record the trampoline for reuse and note it for later initialization
5730 by expand_function_end. */
5733 rtlexp = make_node (RTL_EXPR);
5734 RTL_EXPR_RTL (rtlexp) = tramp;
5735 fp->x_trampoline_list = tree_cons (function, rtlexp,
5736 fp->x_trampoline_list);
5740 /* Make the RTL_EXPR node temporary, not momentary, so that the
5741 trampoline_list doesn't become garbage. */
5742 rtlexp = make_node (RTL_EXPR);
5744 RTL_EXPR_RTL (rtlexp) = tramp;
5745 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5748 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5749 return adjust_trampoline_addr (tramp);
5752 /* Given a trampoline address,
5753 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5756 round_trampoline_addr (tramp)
5759 #ifdef TRAMPOLINE_ALIGNMENT
5760 /* Round address up to desired boundary. */
5761 rtx temp = gen_reg_rtx (Pmode);
5762 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
5763 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5765 temp = expand_simple_binop (Pmode, PLUS, tramp, addend,
5766 temp, 0, OPTAB_LIB_WIDEN);
5767 tramp = expand_simple_binop (Pmode, AND, temp, mask,
5768 temp, 0, OPTAB_LIB_WIDEN);
5773 /* Given a trampoline address, round it then apply any
5774 platform-specific adjustments so that the result can be used for a
5778 adjust_trampoline_addr (tramp)
5781 tramp = round_trampoline_addr (tramp);
5782 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5783 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5788 /* Put all this function's BLOCK nodes including those that are chained
5789 onto the first block into a vector, and return it.
5790 Also store in each NOTE for the beginning or end of a block
5791 the index of that block in the vector.
5792 The arguments are BLOCK, the chain of top-level blocks of the function,
5793 and INSNS, the insn chain of the function. */
5799 tree *block_vector, *last_block_vector;
5801 tree block = DECL_INITIAL (current_function_decl);
5806 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5807 depth-first order. */
5808 block_vector = get_block_vector (block, &n_blocks);
5809 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5811 last_block_vector = identify_blocks_1 (get_insns (),
5813 block_vector + n_blocks,
5816 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5817 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5818 if (0 && last_block_vector != block_vector + n_blocks)
5821 free (block_vector);
5825 /* Subroutine of identify_blocks. Do the block substitution on the
5826 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5828 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5829 BLOCK_VECTOR is incremented for each block seen. */
5832 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5835 tree *end_block_vector;
5836 tree *orig_block_stack;
5839 tree *block_stack = orig_block_stack;
5841 for (insn = insns; insn; insn = NEXT_INSN (insn))
5843 if (GET_CODE (insn) == NOTE)
5845 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5849 /* If there are more block notes than BLOCKs, something
5851 if (block_vector == end_block_vector)
5854 b = *block_vector++;
5855 NOTE_BLOCK (insn) = b;
5858 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5860 /* If there are more NOTE_INSN_BLOCK_ENDs than
5861 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5862 if (block_stack == orig_block_stack)
5865 NOTE_BLOCK (insn) = *--block_stack;
5868 else if (GET_CODE (insn) == CALL_INSN
5869 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5871 rtx cp = PATTERN (insn);
5873 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5874 end_block_vector, block_stack);
5876 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5877 end_block_vector, block_stack);
5879 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5880 end_block_vector, block_stack);
5884 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5885 something is badly wrong. */
5886 if (block_stack != orig_block_stack)
5889 return block_vector;
5892 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5893 and create duplicate blocks. */
5894 /* ??? Need an option to either create block fragments or to create
5895 abstract origin duplicates of a source block. It really depends
5896 on what optimization has been performed. */
5901 tree block = DECL_INITIAL (current_function_decl);
5902 varray_type block_stack;
5904 if (block == NULL_TREE)
5907 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5909 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
5910 reorder_blocks_0 (block);
5912 /* Prune the old trees away, so that they don't get in the way. */
5913 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5914 BLOCK_CHAIN (block) = NULL_TREE;
5916 /* Recreate the block tree from the note nesting. */
5917 reorder_blocks_1 (get_insns (), block, &block_stack);
5918 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5920 /* Remove deleted blocks from the block fragment chains. */
5921 reorder_fix_fragments (block);
5923 VARRAY_FREE (block_stack);
5926 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
5929 reorder_blocks_0 (block)
5934 TREE_ASM_WRITTEN (block) = 0;
5935 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
5936 block = BLOCK_CHAIN (block);
5941 reorder_blocks_1 (insns, current_block, p_block_stack)
5944 varray_type *p_block_stack;
5948 for (insn = insns; insn; insn = NEXT_INSN (insn))
5950 if (GET_CODE (insn) == NOTE)
5952 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5954 tree block = NOTE_BLOCK (insn);
5956 /* If we have seen this block before, that means it now
5957 spans multiple address regions. Create a new fragment. */
5958 if (TREE_ASM_WRITTEN (block))
5960 tree new_block = copy_node (block);
5963 origin = (BLOCK_FRAGMENT_ORIGIN (block)
5964 ? BLOCK_FRAGMENT_ORIGIN (block)
5966 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
5967 BLOCK_FRAGMENT_CHAIN (new_block)
5968 = BLOCK_FRAGMENT_CHAIN (origin);
5969 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
5971 NOTE_BLOCK (insn) = new_block;
5975 BLOCK_SUBBLOCKS (block) = 0;
5976 TREE_ASM_WRITTEN (block) = 1;
5977 BLOCK_SUPERCONTEXT (block) = current_block;
5978 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5979 BLOCK_SUBBLOCKS (current_block) = block;
5980 current_block = block;
5981 VARRAY_PUSH_TREE (*p_block_stack, block);
5983 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5985 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
5986 VARRAY_POP (*p_block_stack);
5987 BLOCK_SUBBLOCKS (current_block)
5988 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5989 current_block = BLOCK_SUPERCONTEXT (current_block);
5992 else if (GET_CODE (insn) == CALL_INSN
5993 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5995 rtx cp = PATTERN (insn);
5996 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
5998 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
6000 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
6005 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
6006 appears in the block tree, select one of the fragments to become
6007 the new origin block. */
6010 reorder_fix_fragments (block)
6015 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
6016 tree new_origin = NULL_TREE;
6020 if (! TREE_ASM_WRITTEN (dup_origin))
6022 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
6024 /* Find the first of the remaining fragments. There must
6025 be at least one -- the current block. */
6026 while (! TREE_ASM_WRITTEN (new_origin))
6027 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
6028 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
6031 else if (! dup_origin)
6034 /* Re-root the rest of the fragments to the new origin. In the
6035 case that DUP_ORIGIN was null, that means BLOCK was the origin
6036 of a chain of fragments and we want to remove those fragments
6037 that didn't make it to the output. */
6040 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
6045 if (TREE_ASM_WRITTEN (chain))
6047 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
6049 pp = &BLOCK_FRAGMENT_CHAIN (chain);
6051 chain = BLOCK_FRAGMENT_CHAIN (chain);
6056 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
6057 block = BLOCK_CHAIN (block);
6061 /* Reverse the order of elements in the chain T of blocks,
6062 and return the new head of the chain (old last element). */
6068 tree prev = 0, decl, next;
6069 for (decl = t; decl; decl = next)
6071 next = BLOCK_CHAIN (decl);
6072 BLOCK_CHAIN (decl) = prev;
6078 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6079 non-NULL, list them all into VECTOR, in a depth-first preorder
6080 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6084 all_blocks (block, vector)
6092 TREE_ASM_WRITTEN (block) = 0;
6094 /* Record this block. */
6096 vector[n_blocks] = block;
6100 /* Record the subblocks, and their subblocks... */
6101 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6102 vector ? vector + n_blocks : 0);
6103 block = BLOCK_CHAIN (block);
6109 /* Return a vector containing all the blocks rooted at BLOCK. The
6110 number of elements in the vector is stored in N_BLOCKS_P. The
6111 vector is dynamically allocated; it is the caller's responsibility
6112 to call `free' on the pointer returned. */
6115 get_block_vector (block, n_blocks_p)
6121 *n_blocks_p = all_blocks (block, NULL);
6122 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
6123 all_blocks (block, block_vector);
6125 return block_vector;
6128 static int next_block_index = 2;
6130 /* Set BLOCK_NUMBER for all the blocks in FN. */
6140 /* For SDB and XCOFF debugging output, we start numbering the blocks
6141 from 1 within each function, rather than keeping a running
6143 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6144 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6145 next_block_index = 1;
6148 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6150 /* The top-level BLOCK isn't numbered at all. */
6151 for (i = 1; i < n_blocks; ++i)
6152 /* We number the blocks from two. */
6153 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6155 free (block_vector);
6160 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6163 debug_find_var_in_block_tree (var, block)
6169 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6173 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6175 tree ret = debug_find_var_in_block_tree (var, t);
6183 /* Allocate a function structure and reset its contents to the defaults. */
6186 prepare_function_start ()
6188 cfun = (struct function *) ggc_alloc_cleared (sizeof (struct function));
6190 init_stmt_for_function ();
6191 init_eh_for_function ();
6193 cse_not_expected = ! optimize;
6195 /* Caller save not needed yet. */
6196 caller_save_needed = 0;
6198 /* No stack slots have been made yet. */
6199 stack_slot_list = 0;
6201 current_function_has_nonlocal_label = 0;
6202 current_function_has_nonlocal_goto = 0;
6204 /* There is no stack slot for handling nonlocal gotos. */
6205 nonlocal_goto_handler_slots = 0;
6206 nonlocal_goto_stack_level = 0;
6208 /* No labels have been declared for nonlocal use. */
6209 nonlocal_labels = 0;
6210 nonlocal_goto_handler_labels = 0;
6212 /* No function calls so far in this function. */
6213 function_call_count = 0;
6215 /* No parm regs have been allocated.
6216 (This is important for output_inline_function.) */
6217 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6219 /* Initialize the RTL mechanism. */
6222 /* Initialize the queue of pending postincrement and postdecrements,
6223 and some other info in expr.c. */
6226 /* We haven't done register allocation yet. */
6229 init_varasm_status (cfun);
6231 /* Clear out data used for inlining. */
6232 cfun->inlinable = 0;
6233 cfun->original_decl_initial = 0;
6234 cfun->original_arg_vector = 0;
6236 cfun->stack_alignment_needed = STACK_BOUNDARY;
6237 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6239 /* Set if a call to setjmp is seen. */
6240 current_function_calls_setjmp = 0;
6242 /* Set if a call to longjmp is seen. */
6243 current_function_calls_longjmp = 0;
6245 current_function_calls_alloca = 0;
6246 current_function_contains_functions = 0;
6247 current_function_is_leaf = 0;
6248 current_function_nothrow = 0;
6249 current_function_sp_is_unchanging = 0;
6250 current_function_uses_only_leaf_regs = 0;
6251 current_function_has_computed_jump = 0;
6252 current_function_is_thunk = 0;
6254 current_function_returns_pcc_struct = 0;
6255 current_function_returns_struct = 0;
6256 current_function_epilogue_delay_list = 0;
6257 current_function_uses_const_pool = 0;
6258 current_function_uses_pic_offset_table = 0;
6259 current_function_cannot_inline = 0;
6261 /* We have not yet needed to make a label to jump to for tail-recursion. */
6262 tail_recursion_label = 0;
6264 /* We haven't had a need to make a save area for ap yet. */
6265 arg_pointer_save_area = 0;
6267 /* No stack slots allocated yet. */
6270 /* No SAVE_EXPRs in this function yet. */
6273 /* No RTL_EXPRs in this function yet. */
6276 /* Set up to allocate temporaries. */
6279 /* Indicate that we need to distinguish between the return value of the
6280 present function and the return value of a function being called. */
6281 rtx_equal_function_value_matters = 1;
6283 /* Indicate that we have not instantiated virtual registers yet. */
6284 virtuals_instantiated = 0;
6286 /* Indicate that we want CONCATs now. */
6287 generating_concat_p = 1;
6289 /* Indicate we have no need of a frame pointer yet. */
6290 frame_pointer_needed = 0;
6292 /* By default assume not varargs or stdarg. */
6293 current_function_varargs = 0;
6294 current_function_stdarg = 0;
6296 /* We haven't made any trampolines for this function yet. */
6297 trampoline_list = 0;
6299 init_pending_stack_adjust ();
6300 inhibit_defer_pop = 0;
6302 current_function_outgoing_args_size = 0;
6304 if (init_lang_status)
6305 (*init_lang_status) (cfun);
6306 if (init_machine_status)
6307 (*init_machine_status) (cfun);
6310 /* Initialize the rtl expansion mechanism so that we can do simple things
6311 like generate sequences. This is used to provide a context during global
6312 initialization of some passes. */
6314 init_dummy_function_start ()
6316 prepare_function_start ();
6319 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6320 and initialize static variables for generating RTL for the statements
6324 init_function_start (subr, filename, line)
6326 const char *filename;
6329 prepare_function_start ();
6331 current_function_name = (*lang_hooks.decl_printable_name) (subr, 2);
6334 /* Nonzero if this is a nested function that uses a static chain. */
6336 current_function_needs_context
6337 = (decl_function_context (current_function_decl) != 0
6338 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6340 /* Within function body, compute a type's size as soon it is laid out. */
6341 immediate_size_expand++;
6343 /* Prevent ever trying to delete the first instruction of a function.
6344 Also tell final how to output a linenum before the function prologue.
6345 Note linenums could be missing, e.g. when compiling a Java .class file. */
6347 emit_line_note (filename, line);
6349 /* Make sure first insn is a note even if we don't want linenums.
6350 This makes sure the first insn will never be deleted.
6351 Also, final expects a note to appear there. */
6352 emit_note (NULL, NOTE_INSN_DELETED);
6354 /* Set flags used by final.c. */
6355 if (aggregate_value_p (DECL_RESULT (subr)))
6357 #ifdef PCC_STATIC_STRUCT_RETURN
6358 current_function_returns_pcc_struct = 1;
6360 current_function_returns_struct = 1;
6363 /* Warn if this value is an aggregate type,
6364 regardless of which calling convention we are using for it. */
6365 if (warn_aggregate_return
6366 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6367 warning ("function returns an aggregate");
6369 current_function_returns_pointer
6370 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
6373 /* Make sure all values used by the optimization passes have sane
6376 init_function_for_compilation ()
6380 /* No prologue/epilogue insns yet. */
6381 VARRAY_GROW (prologue, 0);
6382 VARRAY_GROW (epilogue, 0);
6383 VARRAY_GROW (sibcall_epilogue, 0);
6386 /* Indicate that the current function uses extra args
6387 not explicitly mentioned in the argument list in any fashion. */
6392 current_function_varargs = 1;
6395 /* Expand a call to __main at the beginning of a possible main function. */
6397 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6398 #undef HAS_INIT_SECTION
6399 #define HAS_INIT_SECTION
6403 expand_main_function ()
6405 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6406 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6408 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6412 /* Forcibly align the stack. */
6413 #ifdef STACK_GROWS_DOWNWARD
6414 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6415 stack_pointer_rtx, 1, OPTAB_WIDEN);
6417 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6418 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6419 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6420 stack_pointer_rtx, 1, OPTAB_WIDEN);
6422 if (tmp != stack_pointer_rtx)
6423 emit_move_insn (stack_pointer_rtx, tmp);
6425 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6426 tmp = force_reg (Pmode, const0_rtx);
6427 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6428 seq = gen_sequence ();
6431 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6432 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6435 emit_insn_before (seq, tmp);
6441 #ifndef HAS_INIT_SECTION
6442 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), LCT_NORMAL,
6447 extern struct obstack permanent_obstack;
6449 /* The PENDING_SIZES represent the sizes of variable-sized types.
6450 Create RTL for the various sizes now (using temporary variables),
6451 so that we can refer to the sizes from the RTL we are generating
6452 for the current function. The PENDING_SIZES are a TREE_LIST. The
6453 TREE_VALUE of each node is a SAVE_EXPR. */
6456 expand_pending_sizes (pending_sizes)
6461 /* Evaluate now the sizes of any types declared among the arguments. */
6462 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6464 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6465 /* Flush the queue in case this parameter declaration has
6471 /* Start the RTL for a new function, and set variables used for
6473 SUBR is the FUNCTION_DECL node.
6474 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6475 the function's parameters, which must be run at any return statement. */
6478 expand_function_start (subr, parms_have_cleanups)
6480 int parms_have_cleanups;
6483 rtx last_ptr = NULL_RTX;
6485 /* Make sure volatile mem refs aren't considered
6486 valid operands of arithmetic insns. */
6487 init_recog_no_volatile ();
6489 current_function_instrument_entry_exit
6490 = (flag_instrument_function_entry_exit
6491 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6493 current_function_profile
6495 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6497 current_function_limit_stack
6498 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6500 /* If function gets a static chain arg, store it in the stack frame.
6501 Do this first, so it gets the first stack slot offset. */
6502 if (current_function_needs_context)
6504 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6506 /* Delay copying static chain if it is not a register to avoid
6507 conflicts with regs used for parameters. */
6508 if (! SMALL_REGISTER_CLASSES
6509 || GET_CODE (static_chain_incoming_rtx) == REG)
6510 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6513 /* If the parameters of this function need cleaning up, get a label
6514 for the beginning of the code which executes those cleanups. This must
6515 be done before doing anything with return_label. */
6516 if (parms_have_cleanups)
6517 cleanup_label = gen_label_rtx ();
6521 /* Make the label for return statements to jump to. Do not special
6522 case machines with special return instructions -- they will be
6523 handled later during jump, ifcvt, or epilogue creation. */
6524 return_label = gen_label_rtx ();
6526 /* Initialize rtx used to return the value. */
6527 /* Do this before assign_parms so that we copy the struct value address
6528 before any library calls that assign parms might generate. */
6530 /* Decide whether to return the value in memory or in a register. */
6531 if (aggregate_value_p (DECL_RESULT (subr)))
6533 /* Returning something that won't go in a register. */
6534 rtx value_address = 0;
6536 #ifdef PCC_STATIC_STRUCT_RETURN
6537 if (current_function_returns_pcc_struct)
6539 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6540 value_address = assemble_static_space (size);
6545 /* Expect to be passed the address of a place to store the value.
6546 If it is passed as an argument, assign_parms will take care of
6548 if (struct_value_incoming_rtx)
6550 value_address = gen_reg_rtx (Pmode);
6551 emit_move_insn (value_address, struct_value_incoming_rtx);
6556 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6557 set_mem_attributes (x, DECL_RESULT (subr), 1);
6558 SET_DECL_RTL (DECL_RESULT (subr), x);
6561 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6562 /* If return mode is void, this decl rtl should not be used. */
6563 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6566 /* Compute the return values into a pseudo reg, which we will copy
6567 into the true return register after the cleanups are done. */
6569 /* In order to figure out what mode to use for the pseudo, we
6570 figure out what the mode of the eventual return register will
6571 actually be, and use that. */
6573 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6576 /* Structures that are returned in registers are not aggregate_value_p,
6577 so we may see a PARALLEL. Don't play pseudo games with this. */
6578 if (! REG_P (hard_reg))
6579 SET_DECL_RTL (DECL_RESULT (subr), hard_reg);
6582 /* Create the pseudo. */
6583 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6585 /* Needed because we may need to move this to memory
6586 in case it's a named return value whose address is taken. */
6587 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6591 /* Initialize rtx for parameters and local variables.
6592 In some cases this requires emitting insns. */
6594 assign_parms (subr);
6596 /* Copy the static chain now if it wasn't a register. The delay is to
6597 avoid conflicts with the parameter passing registers. */
6599 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6600 if (GET_CODE (static_chain_incoming_rtx) != REG)
6601 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6603 /* The following was moved from init_function_start.
6604 The move is supposed to make sdb output more accurate. */
6605 /* Indicate the beginning of the function body,
6606 as opposed to parm setup. */
6607 emit_note (NULL, NOTE_INSN_FUNCTION_BEG);
6609 if (GET_CODE (get_last_insn ()) != NOTE)
6610 emit_note (NULL, NOTE_INSN_DELETED);
6611 parm_birth_insn = get_last_insn ();
6613 context_display = 0;
6614 if (current_function_needs_context)
6616 /* Fetch static chain values for containing functions. */
6617 tem = decl_function_context (current_function_decl);
6618 /* Copy the static chain pointer into a pseudo. If we have
6619 small register classes, copy the value from memory if
6620 static_chain_incoming_rtx is a REG. */
6623 /* If the static chain originally came in a register, put it back
6624 there, then move it out in the next insn. The reason for
6625 this peculiar code is to satisfy function integration. */
6626 if (SMALL_REGISTER_CLASSES
6627 && GET_CODE (static_chain_incoming_rtx) == REG)
6628 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6629 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6634 tree rtlexp = make_node (RTL_EXPR);
6636 RTL_EXPR_RTL (rtlexp) = last_ptr;
6637 context_display = tree_cons (tem, rtlexp, context_display);
6638 tem = decl_function_context (tem);
6641 /* Chain thru stack frames, assuming pointer to next lexical frame
6642 is found at the place we always store it. */
6643 #ifdef FRAME_GROWS_DOWNWARD
6644 last_ptr = plus_constant (last_ptr,
6645 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6647 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6648 set_mem_alias_set (last_ptr, get_frame_alias_set ());
6649 last_ptr = copy_to_reg (last_ptr);
6651 /* If we are not optimizing, ensure that we know that this
6652 piece of context is live over the entire function. */
6654 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6659 if (current_function_instrument_entry_exit)
6661 rtx fun = DECL_RTL (current_function_decl);
6662 if (GET_CODE (fun) == MEM)
6663 fun = XEXP (fun, 0);
6666 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode,
6668 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6670 hard_frame_pointer_rtx),
6675 if (current_function_profile)
6676 PROFILE_HOOK (profile_label_no);
6679 /* After the display initializations is where the tail-recursion label
6680 should go, if we end up needing one. Ensure we have a NOTE here
6681 since some things (like trampolines) get placed before this. */
6682 tail_recursion_reentry = emit_note (NULL, NOTE_INSN_DELETED);
6684 /* Evaluate now the sizes of any types declared among the arguments. */
6685 expand_pending_sizes (nreverse (get_pending_sizes ()));
6687 /* Make sure there is a line number after the function entry setup code. */
6688 force_next_line_note ();
6691 /* Undo the effects of init_dummy_function_start. */
6693 expand_dummy_function_end ()
6695 /* End any sequences that failed to be closed due to syntax errors. */
6696 while (in_sequence_p ())
6699 /* Outside function body, can't compute type's actual size
6700 until next function's body starts. */
6702 free_after_parsing (cfun);
6703 free_after_compilation (cfun);
6707 /* Call DOIT for each hard register used as a return value from
6708 the current function. */
6711 diddle_return_value (doit, arg)
6712 void (*doit) PARAMS ((rtx, void *));
6715 rtx outgoing = current_function_return_rtx;
6720 if (GET_CODE (outgoing) == REG)
6721 (*doit) (outgoing, arg);
6722 else if (GET_CODE (outgoing) == PARALLEL)
6726 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6728 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6730 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6737 do_clobber_return_reg (reg, arg)
6739 void *arg ATTRIBUTE_UNUSED;
6741 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6745 clobber_return_register ()
6747 diddle_return_value (do_clobber_return_reg, NULL);
6749 /* In case we do use pseudo to return value, clobber it too. */
6750 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6752 tree decl_result = DECL_RESULT (current_function_decl);
6753 rtx decl_rtl = DECL_RTL (decl_result);
6754 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6756 do_clobber_return_reg (decl_rtl, NULL);
6762 do_use_return_reg (reg, arg)
6764 void *arg ATTRIBUTE_UNUSED;
6766 emit_insn (gen_rtx_USE (VOIDmode, reg));
6770 use_return_register ()
6772 diddle_return_value (do_use_return_reg, NULL);
6775 /* Generate RTL for the end of the current function.
6776 FILENAME and LINE are the current position in the source file.
6778 It is up to language-specific callers to do cleanups for parameters--
6779 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6782 expand_function_end (filename, line, end_bindings)
6783 const char *filename;
6790 #ifdef TRAMPOLINE_TEMPLATE
6791 static rtx initial_trampoline;
6794 finish_expr_for_function ();
6796 /* If arg_pointer_save_area was referenced only from a nested
6797 function, we will not have initialized it yet. Do that now. */
6798 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6799 get_arg_pointer_save_area (cfun);
6801 #ifdef NON_SAVING_SETJMP
6802 /* Don't put any variables in registers if we call setjmp
6803 on a machine that fails to restore the registers. */
6804 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6806 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6807 setjmp_protect (DECL_INITIAL (current_function_decl));
6809 setjmp_protect_args ();
6813 /* Initialize any trampolines required by this function. */
6814 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6816 tree function = TREE_PURPOSE (link);
6817 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6818 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6819 #ifdef TRAMPOLINE_TEMPLATE
6824 #ifdef TRAMPOLINE_TEMPLATE
6825 /* First make sure this compilation has a template for
6826 initializing trampolines. */
6827 if (initial_trampoline == 0)
6830 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6831 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
6833 ggc_add_rtx_root (&initial_trampoline, 1);
6837 /* Generate insns to initialize the trampoline. */
6839 tramp = round_trampoline_addr (XEXP (tramp, 0));
6840 #ifdef TRAMPOLINE_TEMPLATE
6841 blktramp = replace_equiv_address (initial_trampoline, tramp);
6842 emit_block_move (blktramp, initial_trampoline,
6843 GEN_INT (TRAMPOLINE_SIZE));
6845 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6849 /* Put those insns at entry to the containing function (this one). */
6850 emit_insns_before (seq, tail_recursion_reentry);
6853 /* If we are doing stack checking and this function makes calls,
6854 do a stack probe at the start of the function to ensure we have enough
6855 space for another stack frame. */
6856 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6860 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6861 if (GET_CODE (insn) == CALL_INSN)
6864 probe_stack_range (STACK_CHECK_PROTECT,
6865 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6868 emit_insns_before (seq, tail_recursion_reentry);
6873 /* Warn about unused parms if extra warnings were specified. */
6874 /* Either ``-W -Wunused'' or ``-Wunused-parameter'' enables this
6875 warning. WARN_UNUSED_PARAMETER is negative when set by
6877 if (warn_unused_parameter > 0
6878 || (warn_unused_parameter < 0 && extra_warnings))
6882 for (decl = DECL_ARGUMENTS (current_function_decl);
6883 decl; decl = TREE_CHAIN (decl))
6884 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6885 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6886 warning_with_decl (decl, "unused parameter `%s'");
6889 /* Delete handlers for nonlocal gotos if nothing uses them. */
6890 if (nonlocal_goto_handler_slots != 0
6891 && ! current_function_has_nonlocal_label)
6894 /* End any sequences that failed to be closed due to syntax errors. */
6895 while (in_sequence_p ())
6898 /* Outside function body, can't compute type's actual size
6899 until next function's body starts. */
6900 immediate_size_expand--;
6902 clear_pending_stack_adjust ();
6903 do_pending_stack_adjust ();
6905 /* Mark the end of the function body.
6906 If control reaches this insn, the function can drop through
6907 without returning a value. */
6908 emit_note (NULL, NOTE_INSN_FUNCTION_END);
6910 /* Must mark the last line number note in the function, so that the test
6911 coverage code can avoid counting the last line twice. This just tells
6912 the code to ignore the immediately following line note, since there
6913 already exists a copy of this note somewhere above. This line number
6914 note is still needed for debugging though, so we can't delete it. */
6915 if (flag_test_coverage)
6916 emit_note (NULL, NOTE_INSN_REPEATED_LINE_NUMBER);
6918 /* Output a linenumber for the end of the function.
6919 SDB depends on this. */
6920 emit_line_note_force (filename, line);
6922 /* Before the return label (if any), clobber the return
6923 registers so that they are not propagated live to the rest of
6924 the function. This can only happen with functions that drop
6925 through; if there had been a return statement, there would
6926 have either been a return rtx, or a jump to the return label.
6928 We delay actual code generation after the current_function_value_rtx
6930 clobber_after = get_last_insn ();
6932 /* Output the label for the actual return from the function,
6933 if one is expected. This happens either because a function epilogue
6934 is used instead of a return instruction, or because a return was done
6935 with a goto in order to run local cleanups, or because of pcc-style
6936 structure returning. */
6938 emit_label (return_label);
6940 /* C++ uses this. */
6942 expand_end_bindings (0, 0, 0);
6944 if (current_function_instrument_entry_exit)
6946 rtx fun = DECL_RTL (current_function_decl);
6947 if (GET_CODE (fun) == MEM)
6948 fun = XEXP (fun, 0);
6951 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode,
6953 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6955 hard_frame_pointer_rtx),
6959 /* Let except.c know where it should emit the call to unregister
6960 the function context for sjlj exceptions. */
6961 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
6962 sjlj_emit_function_exit_after (get_last_insn ());
6964 /* If we had calls to alloca, and this machine needs
6965 an accurate stack pointer to exit the function,
6966 insert some code to save and restore the stack pointer. */
6967 #ifdef EXIT_IGNORE_STACK
6968 if (! EXIT_IGNORE_STACK)
6970 if (current_function_calls_alloca)
6974 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6975 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6978 /* If scalar return value was computed in a pseudo-reg, or was a named
6979 return value that got dumped to the stack, copy that to the hard
6981 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6983 tree decl_result = DECL_RESULT (current_function_decl);
6984 rtx decl_rtl = DECL_RTL (decl_result);
6986 if (REG_P (decl_rtl)
6987 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
6988 : DECL_REGISTER (decl_result))
6990 rtx real_decl_rtl = current_function_return_rtx;
6992 /* This should be set in assign_parms. */
6993 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
6996 /* If this is a BLKmode structure being returned in registers,
6997 then use the mode computed in expand_return. Note that if
6998 decl_rtl is memory, then its mode may have been changed,
6999 but that current_function_return_rtx has not. */
7000 if (GET_MODE (real_decl_rtl) == BLKmode)
7001 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
7003 /* If a named return value dumped decl_return to memory, then
7004 we may need to re-do the PROMOTE_MODE signed/unsigned
7006 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
7008 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
7010 #ifdef PROMOTE_FUNCTION_RETURN
7011 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
7015 convert_move (real_decl_rtl, decl_rtl, unsignedp);
7017 else if (GET_CODE (real_decl_rtl) == PARALLEL)
7018 emit_group_load (real_decl_rtl, decl_rtl,
7019 int_size_in_bytes (TREE_TYPE (decl_result)));
7021 emit_move_insn (real_decl_rtl, decl_rtl);
7025 /* If returning a structure, arrange to return the address of the value
7026 in a place where debuggers expect to find it.
7028 If returning a structure PCC style,
7029 the caller also depends on this value.
7030 And current_function_returns_pcc_struct is not necessarily set. */
7031 if (current_function_returns_struct
7032 || current_function_returns_pcc_struct)
7035 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
7036 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
7037 #ifdef FUNCTION_OUTGOING_VALUE
7039 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
7040 current_function_decl);
7043 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
7046 /* Mark this as a function return value so integrate will delete the
7047 assignment and USE below when inlining this function. */
7048 REG_FUNCTION_VALUE_P (outgoing) = 1;
7050 #ifdef POINTERS_EXTEND_UNSIGNED
7051 /* The address may be ptr_mode and OUTGOING may be Pmode. */
7052 if (GET_MODE (outgoing) != GET_MODE (value_address))
7053 value_address = convert_memory_address (GET_MODE (outgoing),
7057 emit_move_insn (outgoing, value_address);
7059 /* Show return register used to hold result (in this case the address
7061 current_function_return_rtx = outgoing;
7064 /* If this is an implementation of throw, do what's necessary to
7065 communicate between __builtin_eh_return and the epilogue. */
7066 expand_eh_return ();
7068 /* Emit the actual code to clobber return register. */
7073 clobber_return_register ();
7074 seq = gen_sequence ();
7077 after = emit_insn_after (seq, clobber_after);
7079 if (clobber_after != after)
7080 cfun->x_clobber_return_insn = after;
7083 /* ??? This should no longer be necessary since stupid is no longer with
7084 us, but there are some parts of the compiler (eg reload_combine, and
7085 sh mach_dep_reorg) that still try and compute their own lifetime info
7086 instead of using the general framework. */
7087 use_return_register ();
7089 /* Fix up any gotos that jumped out to the outermost
7090 binding level of the function.
7091 Must follow emitting RETURN_LABEL. */
7093 /* If you have any cleanups to do at this point,
7094 and they need to create temporary variables,
7095 then you will lose. */
7096 expand_fixups (get_insns ());
7100 get_arg_pointer_save_area (f)
7103 rtx ret = f->x_arg_pointer_save_area;
7107 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
7108 f->x_arg_pointer_save_area = ret;
7111 if (f == cfun && ! f->arg_pointer_save_area_init)
7115 /* Save the arg pointer at the beginning of the function. The
7116 generated stack slot may not be a valid memory address, so we
7117 have to check it and fix it if necessary. */
7119 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
7120 seq = gen_sequence ();
7123 push_topmost_sequence ();
7124 emit_insn_after (seq, get_insns ());
7125 pop_topmost_sequence ();
7131 /* Extend a vector that records the INSN_UIDs of INSNS (either a
7132 sequence or a single insn). */
7135 record_insns (insns, vecp)
7139 if (GET_CODE (insns) == SEQUENCE)
7141 int len = XVECLEN (insns, 0);
7142 int i = VARRAY_SIZE (*vecp);
7144 VARRAY_GROW (*vecp, i + len);
7147 VARRAY_INT (*vecp, i) = INSN_UID (XVECEXP (insns, 0, len));
7153 int i = VARRAY_SIZE (*vecp);
7154 VARRAY_GROW (*vecp, i + 1);
7155 VARRAY_INT (*vecp, i) = INSN_UID (insns);
7159 /* Determine how many INSN_UIDs in VEC are part of INSN. */
7162 contains (insn, vec)
7168 if (GET_CODE (insn) == INSN
7169 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7172 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7173 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7174 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7180 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7181 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7188 prologue_epilogue_contains (insn)
7191 if (contains (insn, prologue))
7193 if (contains (insn, epilogue))
7199 sibcall_epilogue_contains (insn)
7202 if (sibcall_epilogue)
7203 return contains (insn, sibcall_epilogue);
7208 /* Insert gen_return at the end of block BB. This also means updating
7209 block_for_insn appropriately. */
7212 emit_return_into_block (bb, line_note)
7218 p = NEXT_INSN (bb->end);
7219 end = emit_jump_insn_after (gen_return (), bb->end);
7221 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
7222 NOTE_LINE_NUMBER (line_note), PREV_INSN (bb->end));
7224 #endif /* HAVE_return */
7226 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7228 /* These functions convert the epilogue into a variant that does not modify the
7229 stack pointer. This is used in cases where a function returns an object
7230 whose size is not known until it is computed. The called function leaves the
7231 object on the stack, leaves the stack depressed, and returns a pointer to
7234 What we need to do is track all modifications and references to the stack
7235 pointer, deleting the modifications and changing the references to point to
7236 the location the stack pointer would have pointed to had the modifications
7239 These functions need to be portable so we need to make as few assumptions
7240 about the epilogue as we can. However, the epilogue basically contains
7241 three things: instructions to reset the stack pointer, instructions to
7242 reload registers, possibly including the frame pointer, and an
7243 instruction to return to the caller.
7245 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7246 We also make no attempt to validate the insns we make since if they are
7247 invalid, we probably can't do anything valid. The intent is that these
7248 routines get "smarter" as more and more machines start to use them and
7249 they try operating on different epilogues.
7251 We use the following structure to track what the part of the epilogue that
7252 we've already processed has done. We keep two copies of the SP equivalence,
7253 one for use during the insn we are processing and one for use in the next
7254 insn. The difference is because one part of a PARALLEL may adjust SP
7255 and the other may use it. */
7259 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7260 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7261 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7262 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7263 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7264 should be set to once we no longer need
7268 static void handle_epilogue_set PARAMS ((rtx, struct epi_info *));
7269 static void emit_equiv_load PARAMS ((struct epi_info *));
7271 /* Modify SEQ, a SEQUENCE that is part of the epilogue, to no modifications
7272 to the stack pointer. Return the new sequence. */
7275 keep_stack_depressed (seq)
7279 struct epi_info info;
7281 /* If the epilogue is just a single instruction, it ust be OK as is. */
7283 if (GET_CODE (seq) != SEQUENCE)
7286 /* Otherwise, start a sequence, initialize the information we have, and
7287 process all the insns we were given. */
7290 info.sp_equiv_reg = stack_pointer_rtx;
7292 info.equiv_reg_src = 0;
7294 for (i = 0; i < XVECLEN (seq, 0); i++)
7296 rtx insn = XVECEXP (seq, 0, i);
7304 /* If this insn references the register that SP is equivalent to and
7305 we have a pending load to that register, we must force out the load
7306 first and then indicate we no longer know what SP's equivalent is. */
7307 if (info.equiv_reg_src != 0
7308 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7310 emit_equiv_load (&info);
7311 info.sp_equiv_reg = 0;
7314 info.new_sp_equiv_reg = info.sp_equiv_reg;
7315 info.new_sp_offset = info.sp_offset;
7317 /* If this is a (RETURN) and the return address is on the stack,
7318 update the address and change to an indirect jump. */
7319 if (GET_CODE (PATTERN (insn)) == RETURN
7320 || (GET_CODE (PATTERN (insn)) == PARALLEL
7321 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7323 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7325 HOST_WIDE_INT offset = 0;
7326 rtx jump_insn, jump_set;
7328 /* If the return address is in a register, we can emit the insn
7329 unchanged. Otherwise, it must be a MEM and we see what the
7330 base register and offset are. In any case, we have to emit any
7331 pending load to the equivalent reg of SP, if any. */
7332 if (GET_CODE (retaddr) == REG)
7334 emit_equiv_load (&info);
7338 else if (GET_CODE (retaddr) == MEM
7339 && GET_CODE (XEXP (retaddr, 0)) == REG)
7340 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7341 else if (GET_CODE (retaddr) == MEM
7342 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7343 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7344 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7346 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7347 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7352 /* If the base of the location containing the return pointer
7353 is SP, we must update it with the replacement address. Otherwise,
7354 just build the necessary MEM. */
7355 retaddr = plus_constant (base, offset);
7356 if (base == stack_pointer_rtx)
7357 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7358 plus_constant (info.sp_equiv_reg,
7361 retaddr = gen_rtx_MEM (Pmode, retaddr);
7363 /* If there is a pending load to the equivalent register for SP
7364 and we reference that register, we must load our address into
7365 a scratch register and then do that load. */
7366 if (info.equiv_reg_src
7367 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7372 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7373 if (HARD_REGNO_MODE_OK (regno, Pmode)
7374 && !fixed_regs[regno]
7375 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7376 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7378 && !refers_to_regno_p (regno,
7379 regno + HARD_REGNO_NREGS (regno,
7381 info.equiv_reg_src, NULL))
7384 if (regno == FIRST_PSEUDO_REGISTER)
7387 reg = gen_rtx_REG (Pmode, regno);
7388 emit_move_insn (reg, retaddr);
7392 emit_equiv_load (&info);
7393 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7395 /* Show the SET in the above insn is a RETURN. */
7396 jump_set = single_set (jump_insn);
7400 SET_IS_RETURN_P (jump_set) = 1;
7403 /* If SP is not mentioned in the pattern and its equivalent register, if
7404 any, is not modified, just emit it. Otherwise, if neither is set,
7405 replace the reference to SP and emit the insn. If none of those are
7406 true, handle each SET individually. */
7407 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7408 && (info.sp_equiv_reg == stack_pointer_rtx
7409 || !reg_set_p (info.sp_equiv_reg, insn)))
7411 else if (! reg_set_p (stack_pointer_rtx, insn)
7412 && (info.sp_equiv_reg == stack_pointer_rtx
7413 || !reg_set_p (info.sp_equiv_reg, insn)))
7415 if (! validate_replace_rtx (stack_pointer_rtx,
7416 plus_constant (info.sp_equiv_reg,
7423 else if (GET_CODE (PATTERN (insn)) == SET)
7424 handle_epilogue_set (PATTERN (insn), &info);
7425 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7427 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7428 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7429 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7434 info.sp_equiv_reg = info.new_sp_equiv_reg;
7435 info.sp_offset = info.new_sp_offset;
7438 seq = gen_sequence ();
7443 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7444 structure that contains information about what we've seen so far. We
7445 process this SET by either updating that data or by emitting one or
7449 handle_epilogue_set (set, p)
7453 /* First handle the case where we are setting SP. Record what it is being
7454 set from. If unknown, abort. */
7455 if (reg_set_p (stack_pointer_rtx, set))
7457 if (SET_DEST (set) != stack_pointer_rtx)
7460 if (GET_CODE (SET_SRC (set)) == PLUS
7461 && GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7463 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7464 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7467 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7469 /* If we are adjusting SP, we adjust from the old data. */
7470 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7472 p->new_sp_equiv_reg = p->sp_equiv_reg;
7473 p->new_sp_offset += p->sp_offset;
7476 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7482 /* Next handle the case where we are setting SP's equivalent register.
7483 If we already have a value to set it to, abort. We could update, but
7484 there seems little point in handling that case. Note that we have
7485 to allow for the case where we are setting the register set in
7486 the previous part of a PARALLEL inside a single insn. But use the
7487 old offset for any updates within this insn. */
7488 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7490 if (!rtx_equal_p (p->new_sp_equiv_reg, SET_DEST (set))
7491 || p->equiv_reg_src != 0)
7495 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7496 plus_constant (p->sp_equiv_reg,
7500 /* Otherwise, replace any references to SP in the insn to its new value
7501 and emit the insn. */
7504 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7505 plus_constant (p->sp_equiv_reg,
7507 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7508 plus_constant (p->sp_equiv_reg,
7514 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7520 if (p->equiv_reg_src != 0)
7521 emit_move_insn (p->sp_equiv_reg, p->equiv_reg_src);
7523 p->equiv_reg_src = 0;
7527 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7528 this into place with notes indicating where the prologue ends and where
7529 the epilogue begins. Update the basic block information when possible. */
7532 thread_prologue_and_epilogue_insns (f)
7533 rtx f ATTRIBUTE_UNUSED;
7537 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7540 #ifdef HAVE_prologue
7541 rtx prologue_end = NULL_RTX;
7543 #if defined (HAVE_epilogue) || defined(HAVE_return)
7544 rtx epilogue_end = NULL_RTX;
7547 #ifdef HAVE_prologue
7551 seq = gen_prologue ();
7554 /* Retain a map of the prologue insns. */
7555 if (GET_CODE (seq) != SEQUENCE)
7557 record_insns (seq, &prologue);
7558 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
7560 seq = gen_sequence ();
7563 /* Can't deal with multiple successors of the entry block
7564 at the moment. Function should always have at least one
7566 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7569 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7574 /* If the exit block has no non-fake predecessors, we don't need
7576 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7577 if ((e->flags & EDGE_FAKE) == 0)
7583 if (optimize && HAVE_return)
7585 /* If we're allowed to generate a simple return instruction,
7586 then by definition we don't need a full epilogue. Examine
7587 the block that falls through to EXIT. If it does not
7588 contain any code, examine its predecessors and try to
7589 emit (conditional) return instructions. */
7595 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7596 if (e->flags & EDGE_FALLTHRU)
7602 /* Verify that there are no active instructions in the last block. */
7604 while (label && GET_CODE (label) != CODE_LABEL)
7606 if (active_insn_p (label))
7608 label = PREV_INSN (label);
7611 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7613 rtx epilogue_line_note = NULL_RTX;
7615 /* Locate the line number associated with the closing brace,
7616 if we can find one. */
7617 for (seq = get_last_insn ();
7618 seq && ! active_insn_p (seq);
7619 seq = PREV_INSN (seq))
7620 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7622 epilogue_line_note = seq;
7626 for (e = last->pred; e; e = e_next)
7628 basic_block bb = e->src;
7631 e_next = e->pred_next;
7632 if (bb == ENTRY_BLOCK_PTR)
7636 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7639 /* If we have an unconditional jump, we can replace that
7640 with a simple return instruction. */
7641 if (simplejump_p (jump))
7643 emit_return_into_block (bb, epilogue_line_note);
7647 /* If we have a conditional jump, we can try to replace
7648 that with a conditional return instruction. */
7649 else if (condjump_p (jump))
7653 ret = SET_SRC (PATTERN (jump));
7654 if (GET_CODE (XEXP (ret, 1)) == LABEL_REF)
7655 loc = &XEXP (ret, 1);
7657 loc = &XEXP (ret, 2);
7658 ret = gen_rtx_RETURN (VOIDmode);
7660 if (! validate_change (jump, loc, ret, 0))
7662 if (JUMP_LABEL (jump))
7663 LABEL_NUSES (JUMP_LABEL (jump))--;
7665 /* If this block has only one successor, it both jumps
7666 and falls through to the fallthru block, so we can't
7668 if (bb->succ->succ_next == NULL)
7674 /* Fix up the CFG for the successful change we just made. */
7675 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7678 /* Emit a return insn for the exit fallthru block. Whether
7679 this is still reachable will be determined later. */
7681 emit_barrier_after (last->end);
7682 emit_return_into_block (last, epilogue_line_note);
7683 epilogue_end = last->end;
7684 last->succ->flags &= ~EDGE_FALLTHRU;
7689 #ifdef HAVE_epilogue
7692 /* Find the edge that falls through to EXIT. Other edges may exist
7693 due to RETURN instructions, but those don't need epilogues.
7694 There really shouldn't be a mixture -- either all should have
7695 been converted or none, however... */
7697 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7698 if (e->flags & EDGE_FALLTHRU)
7704 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
7706 seq = gen_epilogue ();
7708 #ifdef INCOMING_RETURN_ADDR_RTX
7709 /* If this function returns with the stack depressed and we can support
7710 it, massage the epilogue to actually do that. */
7711 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7712 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7713 seq = keep_stack_depressed (seq);
7716 emit_jump_insn (seq);
7718 /* Retain a map of the epilogue insns. */
7719 if (GET_CODE (seq) != SEQUENCE)
7721 record_insns (seq, &epilogue);
7723 seq = gen_sequence ();
7726 insert_insn_on_edge (seq, e);
7733 commit_edge_insertions ();
7735 #ifdef HAVE_sibcall_epilogue
7736 /* Emit sibling epilogues before any sibling call sites. */
7737 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7739 basic_block bb = e->src;
7744 if (GET_CODE (insn) != CALL_INSN
7745 || ! SIBLING_CALL_P (insn))
7749 seq = gen_sibcall_epilogue ();
7752 i = PREV_INSN (insn);
7753 newinsn = emit_insn_before (seq, insn);
7755 /* Retain a map of the epilogue insns. Used in life analysis to
7756 avoid getting rid of sibcall epilogue insns. */
7757 record_insns (GET_CODE (seq) == SEQUENCE
7758 ? seq : newinsn, &sibcall_epilogue);
7762 #ifdef HAVE_prologue
7767 /* GDB handles `break f' by setting a breakpoint on the first
7768 line note after the prologue. Which means (1) that if
7769 there are line number notes before where we inserted the
7770 prologue we should move them, and (2) we should generate a
7771 note before the end of the first basic block, if there isn't
7774 ??? This behaviour is completely broken when dealing with
7775 multiple entry functions. We simply place the note always
7776 into first basic block and let alternate entry points
7780 for (insn = prologue_end; insn; insn = prev)
7782 prev = PREV_INSN (insn);
7783 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7785 /* Note that we cannot reorder the first insn in the
7786 chain, since rest_of_compilation relies on that
7787 remaining constant. */
7790 reorder_insns (insn, insn, prologue_end);
7794 /* Find the last line number note in the first block. */
7795 for (insn = BASIC_BLOCK (0)->end;
7796 insn != prologue_end && insn;
7797 insn = PREV_INSN (insn))
7798 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7801 /* If we didn't find one, make a copy of the first line number
7805 for (insn = next_active_insn (prologue_end);
7807 insn = PREV_INSN (insn))
7808 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7810 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7811 NOTE_LINE_NUMBER (insn),
7818 #ifdef HAVE_epilogue
7823 /* Similarly, move any line notes that appear after the epilogue.
7824 There is no need, however, to be quite so anal about the existence
7826 for (insn = epilogue_end; insn; insn = next)
7828 next = NEXT_INSN (insn);
7829 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7830 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7836 /* Reposition the prologue-end and epilogue-begin notes after instruction
7837 scheduling and delayed branch scheduling. */
7840 reposition_prologue_and_epilogue_notes (f)
7841 rtx f ATTRIBUTE_UNUSED;
7843 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7844 rtx insn, last, note;
7847 if ((len = VARRAY_SIZE (prologue)) > 0)
7851 /* Scan from the beginning until we reach the last prologue insn.
7852 We apparently can't depend on basic_block_{head,end} after
7854 for (insn = f; insn; insn = NEXT_INSN (insn))
7856 if (GET_CODE (insn) == NOTE)
7858 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7861 else if (contains (insn, prologue))
7873 /* Find the prologue-end note if we haven't already, and
7874 move it to just after the last prologue insn. */
7877 for (note = last; (note = NEXT_INSN (note));)
7878 if (GET_CODE (note) == NOTE
7879 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7883 next = NEXT_INSN (note);
7885 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7886 if (GET_CODE (last) == CODE_LABEL)
7887 last = NEXT_INSN (last);
7888 reorder_insns (note, note, last);
7892 if ((len = VARRAY_SIZE (epilogue)) > 0)
7896 /* Scan from the end until we reach the first epilogue insn.
7897 We apparently can't depend on basic_block_{head,end} after
7899 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
7901 if (GET_CODE (insn) == NOTE)
7903 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7906 else if (contains (insn, epilogue))
7916 /* Find the epilogue-begin note if we haven't already, and
7917 move it to just before the first epilogue insn. */
7920 for (note = insn; (note = PREV_INSN (note));)
7921 if (GET_CODE (note) == NOTE
7922 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7926 if (PREV_INSN (last) != note)
7927 reorder_insns (note, note, PREV_INSN (last));
7930 #endif /* HAVE_prologue or HAVE_epilogue */
7933 /* Mark P for GC. */
7936 mark_function_status (p)
7939 struct var_refs_queue *q;
7940 struct temp_slot *t;
7947 ggc_mark_rtx (p->arg_offset_rtx);
7949 if (p->x_parm_reg_stack_loc)
7950 for (i = p->x_max_parm_reg, r = p->x_parm_reg_stack_loc;
7954 ggc_mark_rtx (p->return_rtx);
7955 ggc_mark_rtx (p->x_cleanup_label);
7956 ggc_mark_rtx (p->x_return_label);
7957 ggc_mark_rtx (p->x_save_expr_regs);
7958 ggc_mark_rtx (p->x_stack_slot_list);
7959 ggc_mark_rtx (p->x_parm_birth_insn);
7960 ggc_mark_rtx (p->x_tail_recursion_label);
7961 ggc_mark_rtx (p->x_tail_recursion_reentry);
7962 ggc_mark_rtx (p->internal_arg_pointer);
7963 ggc_mark_rtx (p->x_arg_pointer_save_area);
7964 ggc_mark_tree (p->x_rtl_expr_chain);
7965 ggc_mark_rtx (p->x_last_parm_insn);
7966 ggc_mark_tree (p->x_context_display);
7967 ggc_mark_tree (p->x_trampoline_list);
7968 ggc_mark_rtx (p->epilogue_delay_list);
7969 ggc_mark_rtx (p->x_clobber_return_insn);
7971 for (t = p->x_temp_slots; t != 0; t = t->next)
7974 ggc_mark_rtx (t->slot);
7975 ggc_mark_rtx (t->address);
7976 ggc_mark_tree (t->rtl_expr);
7977 ggc_mark_tree (t->type);
7980 for (q = p->fixup_var_refs_queue; q != 0; q = q->next)
7983 ggc_mark_rtx (q->modified);
7986 ggc_mark_rtx (p->x_nonlocal_goto_handler_slots);
7987 ggc_mark_rtx (p->x_nonlocal_goto_handler_labels);
7988 ggc_mark_rtx (p->x_nonlocal_goto_stack_level);
7989 ggc_mark_tree (p->x_nonlocal_labels);
7991 mark_hard_reg_initial_vals (p);
7994 /* Mark the struct function pointed to by *ARG for GC, if it is not
7995 NULL. This is used to mark the current function and the outer
7999 maybe_mark_struct_function (arg)
8002 struct function *f = *(struct function **) arg;
8007 ggc_mark_struct_function (f);
8010 /* Mark a struct function * for GC. This is called from ggc-common.c. */
8013 ggc_mark_struct_function (f)
8017 ggc_mark_tree (f->decl);
8019 mark_function_status (f);
8020 mark_eh_status (f->eh);
8021 mark_stmt_status (f->stmt);
8022 mark_expr_status (f->expr);
8023 mark_emit_status (f->emit);
8024 mark_varasm_status (f->varasm);
8026 if (mark_machine_status)
8027 (*mark_machine_status) (f);
8028 if (mark_lang_status)
8029 (*mark_lang_status) (f);
8031 if (f->original_arg_vector)
8032 ggc_mark_rtvec ((rtvec) f->original_arg_vector);
8033 if (f->original_decl_initial)
8034 ggc_mark_tree (f->original_decl_initial);
8036 ggc_mark_struct_function (f->outer);
8039 /* Called once, at initialization, to initialize function.c. */
8042 init_function_once ()
8044 ggc_add_root (&cfun, 1, sizeof cfun, maybe_mark_struct_function);
8045 ggc_add_root (&outer_function_chain, 1, sizeof outer_function_chain,
8046 maybe_mark_struct_function);
8048 VARRAY_INT_INIT (prologue, 0, "prologue");
8049 VARRAY_INT_INIT (epilogue, 0, "epilogue");
8050 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");