1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register.
36 Call `put_var_into_stack' when you learn, belatedly, that a variable
37 previously given a pseudo-register must in fact go in the stack.
38 This function changes the DECL_RTL to be a stack slot instead of a reg
39 then scans all the RTL instructions so far generated to correct them. */
43 #include "coretypes.h"
54 #include "hard-reg-set.h"
55 #include "insn-config.h"
58 #include "basic-block.h"
63 #include "integrate.h"
64 #include "langhooks.h"
67 #ifndef TRAMPOLINE_ALIGNMENT
68 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
71 #ifndef LOCAL_ALIGNMENT
72 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
75 #ifndef STACK_ALIGNMENT_NEEDED
76 #define STACK_ALIGNMENT_NEEDED 1
79 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
81 /* Some systems use __main in a way incompatible with its use in gcc, in these
82 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
83 give the same symbol without quotes for an alternative entry point. You
84 must define both, or neither. */
86 #define NAME__MAIN "__main"
89 /* Round a value to the lowest integer less than it that is a multiple of
90 the required alignment. Avoid using division in case the value is
91 negative. Assume the alignment is a power of two. */
92 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
94 /* Similar, but round to the next highest integer that meets the
96 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
98 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
99 during rtl generation. If they are different register numbers, this is
100 always true. It may also be true if
101 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
102 generation. See fix_lexical_addr for details. */
104 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
105 #define NEED_SEPARATE_AP
108 /* Nonzero if function being compiled doesn't contain any calls
109 (ignoring the prologue and epilogue). This is set prior to
110 local register allocation and is valid for the remaining
112 int current_function_is_leaf
;
114 /* Nonzero if function being compiled doesn't contain any instructions
115 that can throw an exception. This is set prior to final. */
117 int current_function_nothrow
;
119 /* Nonzero if function being compiled doesn't modify the stack pointer
120 (ignoring the prologue and epilogue). This is only valid after
121 life_analysis has run. */
122 int current_function_sp_is_unchanging
;
124 /* Nonzero if the function being compiled is a leaf function which only
125 uses leaf registers. This is valid after reload (specifically after
126 sched2) and is useful only if the port defines LEAF_REGISTERS. */
127 int current_function_uses_only_leaf_regs
;
129 /* Nonzero once virtual register instantiation has been done.
130 assign_stack_local uses frame_pointer_rtx when this is nonzero.
131 calls.c:emit_library_call_value_1 uses it to set up
132 post-instantiation libcalls. */
133 int virtuals_instantiated
;
135 /* Nonzero if at least one trampoline has been created. */
136 int trampolines_created
;
138 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
139 static GTY(()) int funcdef_no
;
141 /* These variables hold pointers to functions to create and destroy
142 target specific, per-function data structures. */
143 struct machine_function
* (*init_machine_status
) (void);
145 /* The FUNCTION_DECL for an inline function currently being expanded. */
146 tree inline_function_decl
;
148 /* The currently compiled function. */
149 struct function
*cfun
= 0;
151 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
152 static GTY(()) varray_type prologue
;
153 static GTY(()) varray_type epilogue
;
155 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
157 static GTY(()) varray_type sibcall_epilogue
;
159 /* In order to evaluate some expressions, such as function calls returning
160 structures in memory, we need to temporarily allocate stack locations.
161 We record each allocated temporary in the following structure.
163 Associated with each temporary slot is a nesting level. When we pop up
164 one level, all temporaries associated with the previous level are freed.
165 Normally, all temporaries are freed after the execution of the statement
166 in which they were created. However, if we are inside a ({...}) grouping,
167 the result may be in a temporary and hence must be preserved. If the
168 result could be in a temporary, we preserve it if we can determine which
169 one it is in. If we cannot determine which temporary may contain the
170 result, all temporaries are preserved. A temporary is preserved by
171 pretending it was allocated at the previous nesting level.
173 Automatic variables are also assigned temporary slots, at the nesting
174 level where they are defined. They are marked a "kept" so that
175 free_temp_slots will not free them. */
177 struct temp_slot
GTY(())
179 /* Points to next temporary slot. */
180 struct temp_slot
*next
;
181 /* The rtx to used to reference the slot. */
183 /* The rtx used to represent the address if not the address of the
184 slot above. May be an EXPR_LIST if multiple addresses exist. */
186 /* The alignment (in bits) of the slot. */
188 /* The size, in units, of the slot. */
190 /* The type of the object in the slot, or zero if it doesn't correspond
191 to a type. We use this to determine whether a slot can be reused.
192 It can be reused if objects of the type of the new slot will always
193 conflict with objects of the type of the old slot. */
195 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
197 /* Nonzero if this temporary is currently in use. */
199 /* Nonzero if this temporary has its address taken. */
201 /* Nesting level at which this slot is being used. */
203 /* Nonzero if this should survive a call to free_temp_slots. */
205 /* The offset of the slot from the frame_pointer, including extra space
206 for alignment. This info is for combine_temp_slots. */
207 HOST_WIDE_INT base_offset
;
208 /* The size of the slot, including extra space for alignment. This
209 info is for combine_temp_slots. */
210 HOST_WIDE_INT full_size
;
213 /* This structure is used to record MEMs or pseudos used to replace VAR, any
214 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
215 maintain this list in case two operands of an insn were required to match;
216 in that case we must ensure we use the same replacement. */
218 struct fixup_replacement
GTY(())
222 struct fixup_replacement
*next
;
225 struct insns_for_mem_entry
229 /* These are the INSNs which reference the MEM. */
233 /* Forward declarations. */
235 static rtx
assign_stack_local_1 (enum machine_mode
, HOST_WIDE_INT
, int,
237 static struct temp_slot
*find_temp_slot_from_address (rtx
);
238 static void put_reg_into_stack (struct function
*, rtx
, tree
, enum machine_mode
,
239 enum machine_mode
, int, unsigned int, int, htab_t
);
240 static void schedule_fixup_var_refs (struct function
*, rtx
, tree
, enum machine_mode
,
242 static void fixup_var_refs (rtx
, enum machine_mode
, int, rtx
, htab_t
);
243 static struct fixup_replacement
244 *find_fixup_replacement (struct fixup_replacement
**, rtx
);
245 static void fixup_var_refs_insns (rtx
, rtx
, enum machine_mode
, int, int, rtx
);
246 static void fixup_var_refs_insns_with_hash (htab_t
, rtx
, enum machine_mode
, int, rtx
);
247 static void fixup_var_refs_insn (rtx
, rtx
, enum machine_mode
, int, int, rtx
);
248 static void fixup_var_refs_1 (rtx
, enum machine_mode
, rtx
*, rtx
,
249 struct fixup_replacement
**, rtx
);
250 static rtx
fixup_memory_subreg (rtx
, rtx
, enum machine_mode
, int);
251 static rtx
walk_fixup_memory_subreg (rtx
, rtx
, enum machine_mode
, int);
252 static rtx
fixup_stack_1 (rtx
, rtx
);
253 static void optimize_bit_field (rtx
, rtx
, rtx
*);
254 static void instantiate_decls (tree
, int);
255 static void instantiate_decls_1 (tree
, int);
256 static void instantiate_decl (rtx
, HOST_WIDE_INT
, int);
257 static rtx
instantiate_new_reg (rtx
, HOST_WIDE_INT
*);
258 static int instantiate_virtual_regs_1 (rtx
*, rtx
, int);
259 static void delete_handlers (void);
260 static void pad_to_arg_alignment (struct args_size
*, int, struct args_size
*);
261 static void pad_below (struct args_size
*, enum machine_mode
, tree
);
262 static rtx
round_trampoline_addr (rtx
);
263 static rtx
adjust_trampoline_addr (rtx
);
264 static tree
*identify_blocks_1 (rtx
, tree
*, tree
*, tree
*);
265 static void reorder_blocks_0 (tree
);
266 static void reorder_blocks_1 (rtx
, tree
, varray_type
*);
267 static void reorder_fix_fragments (tree
);
268 static tree
blocks_nreverse (tree
);
269 static int all_blocks (tree
, tree
*);
270 static tree
*get_block_vector (tree
, int *);
271 extern tree
debug_find_var_in_block_tree (tree
, tree
);
272 /* We always define `record_insns' even if it's not used so that we
273 can always export `prologue_epilogue_contains'. */
274 static void record_insns (rtx
, varray_type
*) ATTRIBUTE_UNUSED
;
275 static int contains (rtx
, varray_type
);
277 static void emit_return_into_block (basic_block
, rtx
);
279 static void put_addressof_into_stack (rtx
, htab_t
);
280 static bool purge_addressof_1 (rtx
*, rtx
, int, int, int, htab_t
);
281 static void purge_single_hard_subreg_set (rtx
);
282 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
283 static rtx
keep_stack_depressed (rtx
);
285 static int is_addressof (rtx
*, void *);
286 static hashval_t
insns_for_mem_hash (const void *);
287 static int insns_for_mem_comp (const void *, const void *);
288 static int insns_for_mem_walk (rtx
*, void *);
289 static void compute_insns_for_mem (rtx
, rtx
, htab_t
);
290 static void prepare_function_start (tree
);
291 static void do_clobber_return_reg (rtx
, void *);
292 static void do_use_return_reg (rtx
, void *);
293 static void instantiate_virtual_regs_lossage (rtx
);
294 static tree
split_complex_args (tree
);
295 static void set_insn_locators (rtx
, int) ATTRIBUTE_UNUSED
;
297 /* Pointer to chain of `struct function' for containing functions. */
298 struct function
*outer_function_chain
;
300 /* List of insns that were postponed by purge_addressof_1. */
301 static rtx postponed_insns
;
303 /* Given a function decl for a containing function,
304 return the `struct function' for it. */
307 find_function_data (tree decl
)
311 for (p
= outer_function_chain
; p
; p
= p
->outer
)
318 /* Save the current context for compilation of a nested function.
319 This is called from language-specific code. The caller should use
320 the enter_nested langhook to save any language-specific state,
321 since this function knows only about language-independent
325 push_function_context_to (tree context
)
331 if (context
== current_function_decl
)
332 cfun
->contains_functions
= 1;
335 struct function
*containing
= find_function_data (context
);
336 containing
->contains_functions
= 1;
341 init_dummy_function_start ();
344 p
->outer
= outer_function_chain
;
345 outer_function_chain
= p
;
346 p
->fixup_var_refs_queue
= 0;
348 lang_hooks
.function
.enter_nested (p
);
354 push_function_context (void)
356 push_function_context_to (current_function_decl
);
359 /* Restore the last saved context, at the end of a nested function.
360 This function is called from language-specific code. */
363 pop_function_context_from (tree context ATTRIBUTE_UNUSED
)
365 struct function
*p
= outer_function_chain
;
366 struct var_refs_queue
*queue
;
369 outer_function_chain
= p
->outer
;
371 current_function_decl
= p
->decl
;
374 restore_emit_status (p
);
376 lang_hooks
.function
.leave_nested (p
);
378 /* Finish doing put_var_into_stack for any of our variables which became
379 addressable during the nested function. If only one entry has to be
380 fixed up, just do that one. Otherwise, first make a list of MEMs that
381 are not to be unshared. */
382 if (p
->fixup_var_refs_queue
== 0)
384 else if (p
->fixup_var_refs_queue
->next
== 0)
385 fixup_var_refs (p
->fixup_var_refs_queue
->modified
,
386 p
->fixup_var_refs_queue
->promoted_mode
,
387 p
->fixup_var_refs_queue
->unsignedp
,
388 p
->fixup_var_refs_queue
->modified
, 0);
393 for (queue
= p
->fixup_var_refs_queue
; queue
; queue
= queue
->next
)
394 list
= gen_rtx_EXPR_LIST (VOIDmode
, queue
->modified
, list
);
396 for (queue
= p
->fixup_var_refs_queue
; queue
; queue
= queue
->next
)
397 fixup_var_refs (queue
->modified
, queue
->promoted_mode
,
398 queue
->unsignedp
, list
, 0);
402 p
->fixup_var_refs_queue
= 0;
404 /* Reset variables that have known state during rtx generation. */
405 rtx_equal_function_value_matters
= 1;
406 virtuals_instantiated
= 0;
407 generating_concat_p
= 1;
411 pop_function_context (void)
413 pop_function_context_from (current_function_decl
);
416 /* Clear out all parts of the state in F that can safely be discarded
417 after the function has been parsed, but not compiled, to let
418 garbage collection reclaim the memory. */
421 free_after_parsing (struct function
*f
)
423 /* f->expr->forced_labels is used by code generation. */
424 /* f->emit->regno_reg_rtx is used by code generation. */
425 /* f->varasm is used by code generation. */
426 /* f->eh->eh_return_stub_label is used by code generation. */
428 lang_hooks
.function
.final (f
);
432 /* Clear out all parts of the state in F that can safely be discarded
433 after the function has been compiled, to let garbage collection
434 reclaim the memory. */
437 free_after_compilation (struct function
*f
)
445 f
->x_temp_slots
= NULL
;
446 f
->arg_offset_rtx
= NULL
;
447 f
->return_rtx
= NULL
;
448 f
->internal_arg_pointer
= NULL
;
449 f
->x_nonlocal_labels
= NULL
;
450 f
->x_nonlocal_goto_handler_slots
= NULL
;
451 f
->x_nonlocal_goto_handler_labels
= NULL
;
452 f
->x_nonlocal_goto_stack_level
= NULL
;
453 f
->x_cleanup_label
= NULL
;
454 f
->x_return_label
= NULL
;
455 f
->x_naked_return_label
= NULL
;
456 f
->computed_goto_common_label
= NULL
;
457 f
->computed_goto_common_reg
= NULL
;
458 f
->x_save_expr_regs
= NULL
;
459 f
->x_stack_slot_list
= NULL
;
460 f
->x_rtl_expr_chain
= NULL
;
461 f
->x_tail_recursion_label
= NULL
;
462 f
->x_tail_recursion_reentry
= NULL
;
463 f
->x_arg_pointer_save_area
= NULL
;
464 f
->x_clobber_return_insn
= NULL
;
465 f
->x_context_display
= NULL
;
466 f
->x_trampoline_list
= NULL
;
467 f
->x_parm_birth_insn
= NULL
;
468 f
->x_last_parm_insn
= NULL
;
469 f
->x_parm_reg_stack_loc
= NULL
;
470 f
->fixup_var_refs_queue
= NULL
;
471 f
->original_arg_vector
= NULL
;
472 f
->original_decl_initial
= NULL
;
473 f
->inl_last_parm_insn
= NULL
;
474 f
->epilogue_delay_list
= NULL
;
477 /* Allocate fixed slots in the stack frame of the current function. */
479 /* Return size needed for stack frame based on slots so far allocated in
481 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
482 the caller may have to do that. */
485 get_func_frame_size (struct function
*f
)
487 #ifdef FRAME_GROWS_DOWNWARD
488 return -f
->x_frame_offset
;
490 return f
->x_frame_offset
;
494 /* Return size needed for stack frame based on slots so far allocated.
495 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
496 the caller may have to do that. */
498 get_frame_size (void)
500 return get_func_frame_size (cfun
);
503 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
504 with machine mode MODE.
506 ALIGN controls the amount of alignment for the address of the slot:
507 0 means according to MODE,
508 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
509 positive specifies alignment boundary in bits.
511 We do not round to stack_boundary here.
513 FUNCTION specifies the function to allocate in. */
516 assign_stack_local_1 (enum machine_mode mode
, HOST_WIDE_INT size
, int align
,
517 struct function
*function
)
520 int bigend_correction
= 0;
522 int frame_off
, frame_alignment
, frame_phase
;
529 alignment
= BIGGEST_ALIGNMENT
;
531 alignment
= GET_MODE_ALIGNMENT (mode
);
533 /* Allow the target to (possibly) increase the alignment of this
535 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
537 alignment
= LOCAL_ALIGNMENT (type
, alignment
);
539 alignment
/= BITS_PER_UNIT
;
541 else if (align
== -1)
543 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
544 size
= CEIL_ROUND (size
, alignment
);
547 alignment
= align
/ BITS_PER_UNIT
;
549 #ifdef FRAME_GROWS_DOWNWARD
550 function
->x_frame_offset
-= size
;
553 /* Ignore alignment we can't do with expected alignment of the boundary. */
554 if (alignment
* BITS_PER_UNIT
> PREFERRED_STACK_BOUNDARY
)
555 alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
557 if (function
->stack_alignment_needed
< alignment
* BITS_PER_UNIT
)
558 function
->stack_alignment_needed
= alignment
* BITS_PER_UNIT
;
560 /* Calculate how many bytes the start of local variables is off from
562 frame_alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
563 frame_off
= STARTING_FRAME_OFFSET
% frame_alignment
;
564 frame_phase
= frame_off
? frame_alignment
- frame_off
: 0;
566 /* Round the frame offset to the specified alignment. The default is
567 to always honor requests to align the stack but a port may choose to
568 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
569 if (STACK_ALIGNMENT_NEEDED
573 /* We must be careful here, since FRAME_OFFSET might be negative and
574 division with a negative dividend isn't as well defined as we might
575 like. So we instead assume that ALIGNMENT is a power of two and
576 use logical operations which are unambiguous. */
577 #ifdef FRAME_GROWS_DOWNWARD
578 function
->x_frame_offset
579 = (FLOOR_ROUND (function
->x_frame_offset
- frame_phase
, alignment
)
582 function
->x_frame_offset
583 = (CEIL_ROUND (function
->x_frame_offset
- frame_phase
, alignment
)
588 /* On a big-endian machine, if we are allocating more space than we will use,
589 use the least significant bytes of those that are allocated. */
590 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
)
591 bigend_correction
= size
- GET_MODE_SIZE (mode
);
593 /* If we have already instantiated virtual registers, return the actual
594 address relative to the frame pointer. */
595 if (function
== cfun
&& virtuals_instantiated
)
596 addr
= plus_constant (frame_pointer_rtx
,
598 (frame_offset
+ bigend_correction
599 + STARTING_FRAME_OFFSET
, Pmode
));
601 addr
= plus_constant (virtual_stack_vars_rtx
,
603 (function
->x_frame_offset
+ bigend_correction
,
606 #ifndef FRAME_GROWS_DOWNWARD
607 function
->x_frame_offset
+= size
;
610 x
= gen_rtx_MEM (mode
, addr
);
612 function
->x_stack_slot_list
613 = gen_rtx_EXPR_LIST (VOIDmode
, x
, function
->x_stack_slot_list
);
618 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
622 assign_stack_local (enum machine_mode mode
, HOST_WIDE_INT size
, int align
)
624 return assign_stack_local_1 (mode
, size
, align
, cfun
);
627 /* Allocate a temporary stack slot and record it for possible later
630 MODE is the machine mode to be given to the returned rtx.
632 SIZE is the size in units of the space required. We do no rounding here
633 since assign_stack_local will do any required rounding.
635 KEEP is 1 if this slot is to be retained after a call to
636 free_temp_slots. Automatic variables for a block are allocated
637 with this flag. KEEP is 2 if we allocate a longer term temporary,
638 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
639 if we are to allocate something at an inner level to be treated as
640 a variable in the block (e.g., a SAVE_EXPR).
642 TYPE is the type that will be used for the stack slot. */
645 assign_stack_temp_for_type (enum machine_mode mode
, HOST_WIDE_INT size
, int keep
,
649 struct temp_slot
*p
, *best_p
= 0;
652 /* If SIZE is -1 it means that somebody tried to allocate a temporary
653 of a variable size. */
658 align
= BIGGEST_ALIGNMENT
;
660 align
= GET_MODE_ALIGNMENT (mode
);
663 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
666 align
= LOCAL_ALIGNMENT (type
, align
);
668 /* Try to find an available, already-allocated temporary of the proper
669 mode which meets the size and alignment requirements. Choose the
670 smallest one with the closest alignment. */
671 for (p
= temp_slots
; p
; p
= p
->next
)
672 if (p
->align
>= align
&& p
->size
>= size
&& GET_MODE (p
->slot
) == mode
674 && objects_must_conflict_p (p
->type
, type
)
675 && (best_p
== 0 || best_p
->size
> p
->size
676 || (best_p
->size
== p
->size
&& best_p
->align
> p
->align
)))
678 if (p
->align
== align
&& p
->size
== size
)
686 /* Make our best, if any, the one to use. */
689 /* If there are enough aligned bytes left over, make them into a new
690 temp_slot so that the extra bytes don't get wasted. Do this only
691 for BLKmode slots, so that we can be sure of the alignment. */
692 if (GET_MODE (best_p
->slot
) == BLKmode
)
694 int alignment
= best_p
->align
/ BITS_PER_UNIT
;
695 HOST_WIDE_INT rounded_size
= CEIL_ROUND (size
, alignment
);
697 if (best_p
->size
- rounded_size
>= alignment
)
699 p
= ggc_alloc (sizeof (struct temp_slot
));
700 p
->in_use
= p
->addr_taken
= 0;
701 p
->size
= best_p
->size
- rounded_size
;
702 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
703 p
->full_size
= best_p
->full_size
- rounded_size
;
704 p
->slot
= gen_rtx_MEM (BLKmode
,
705 plus_constant (XEXP (best_p
->slot
, 0),
707 p
->align
= best_p
->align
;
710 p
->type
= best_p
->type
;
711 p
->next
= temp_slots
;
714 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, p
->slot
,
717 best_p
->size
= rounded_size
;
718 best_p
->full_size
= rounded_size
;
725 /* If we still didn't find one, make a new temporary. */
728 HOST_WIDE_INT frame_offset_old
= frame_offset
;
730 p
= ggc_alloc (sizeof (struct temp_slot
));
732 /* We are passing an explicit alignment request to assign_stack_local.
733 One side effect of that is assign_stack_local will not round SIZE
734 to ensure the frame offset remains suitably aligned.
736 So for requests which depended on the rounding of SIZE, we go ahead
737 and round it now. We also make sure ALIGNMENT is at least
738 BIGGEST_ALIGNMENT. */
739 if (mode
== BLKmode
&& align
< BIGGEST_ALIGNMENT
)
741 p
->slot
= assign_stack_local (mode
,
743 ? CEIL_ROUND (size
, (int) align
/ BITS_PER_UNIT
)
749 /* The following slot size computation is necessary because we don't
750 know the actual size of the temporary slot until assign_stack_local
751 has performed all the frame alignment and size rounding for the
752 requested temporary. Note that extra space added for alignment
753 can be either above or below this stack slot depending on which
754 way the frame grows. We include the extra space if and only if it
755 is above this slot. */
756 #ifdef FRAME_GROWS_DOWNWARD
757 p
->size
= frame_offset_old
- frame_offset
;
762 /* Now define the fields used by combine_temp_slots. */
763 #ifdef FRAME_GROWS_DOWNWARD
764 p
->base_offset
= frame_offset
;
765 p
->full_size
= frame_offset_old
- frame_offset
;
767 p
->base_offset
= frame_offset_old
;
768 p
->full_size
= frame_offset
- frame_offset_old
;
771 p
->next
= temp_slots
;
777 p
->rtl_expr
= seq_rtl_expr
;
782 p
->level
= target_temp_slot_level
;
787 p
->level
= var_temp_slot_level
;
792 p
->level
= temp_slot_level
;
797 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
798 slot
= gen_rtx_MEM (mode
, XEXP (p
->slot
, 0));
799 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, slot
, stack_slot_list
);
801 /* If we know the alias set for the memory that will be used, use
802 it. If there's no TYPE, then we don't know anything about the
803 alias set for the memory. */
804 set_mem_alias_set (slot
, type
? get_alias_set (type
) : 0);
805 set_mem_align (slot
, align
);
807 /* If a type is specified, set the relevant flags. */
810 RTX_UNCHANGING_P (slot
) = (lang_hooks
.honor_readonly
811 && TYPE_READONLY (type
));
812 MEM_VOLATILE_P (slot
) = TYPE_VOLATILE (type
);
813 MEM_SET_IN_STRUCT_P (slot
, AGGREGATE_TYPE_P (type
));
819 /* Allocate a temporary stack slot and record it for possible later
820 reuse. First three arguments are same as in preceding function. */
823 assign_stack_temp (enum machine_mode mode
, HOST_WIDE_INT size
, int keep
)
825 return assign_stack_temp_for_type (mode
, size
, keep
, NULL_TREE
);
828 /* Assign a temporary.
829 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
830 and so that should be used in error messages. In either case, we
831 allocate of the given type.
832 KEEP is as for assign_stack_temp.
833 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
834 it is 0 if a register is OK.
835 DONT_PROMOTE is 1 if we should not promote values in register
839 assign_temp (tree type_or_decl
, int keep
, int memory_required
,
840 int dont_promote ATTRIBUTE_UNUSED
)
843 enum machine_mode mode
;
844 #ifndef PROMOTE_FOR_CALL_ONLY
848 if (DECL_P (type_or_decl
))
849 decl
= type_or_decl
, type
= TREE_TYPE (decl
);
851 decl
= NULL
, type
= type_or_decl
;
853 mode
= TYPE_MODE (type
);
854 #ifndef PROMOTE_FOR_CALL_ONLY
855 unsignedp
= TREE_UNSIGNED (type
);
858 if (mode
== BLKmode
|| memory_required
)
860 HOST_WIDE_INT size
= int_size_in_bytes (type
);
863 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
864 problems with allocating the stack space. */
868 /* Unfortunately, we don't yet know how to allocate variable-sized
869 temporaries. However, sometimes we have a fixed upper limit on
870 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
871 instead. This is the case for Chill variable-sized strings. */
872 if (size
== -1 && TREE_CODE (type
) == ARRAY_TYPE
873 && TYPE_ARRAY_MAX_SIZE (type
) != NULL_TREE
874 && host_integerp (TYPE_ARRAY_MAX_SIZE (type
), 1))
875 size
= tree_low_cst (TYPE_ARRAY_MAX_SIZE (type
), 1);
877 /* The size of the temporary may be too large to fit into an integer. */
878 /* ??? Not sure this should happen except for user silliness, so limit
879 this to things that aren't compiler-generated temporaries. The
880 rest of the time we'll abort in assign_stack_temp_for_type. */
881 if (decl
&& size
== -1
882 && TREE_CODE (TYPE_SIZE_UNIT (type
)) == INTEGER_CST
)
884 error ("%Jsize of variable '%D' is too large", decl
, decl
);
888 tmp
= assign_stack_temp_for_type (mode
, size
, keep
, type
);
892 #ifndef PROMOTE_FOR_CALL_ONLY
894 mode
= promote_mode (type
, mode
, &unsignedp
, 0);
897 return gen_reg_rtx (mode
);
900 /* Combine temporary stack slots which are adjacent on the stack.
902 This allows for better use of already allocated stack space. This is only
903 done for BLKmode slots because we can be sure that we won't have alignment
904 problems in this case. */
907 combine_temp_slots (void)
909 struct temp_slot
*p
, *q
;
910 struct temp_slot
*prev_p
, *prev_q
;
913 /* We can't combine slots, because the information about which slot
914 is in which alias set will be lost. */
915 if (flag_strict_aliasing
)
918 /* If there are a lot of temp slots, don't do anything unless
919 high levels of optimization. */
920 if (! flag_expensive_optimizations
)
921 for (p
= temp_slots
, num_slots
= 0; p
; p
= p
->next
, num_slots
++)
922 if (num_slots
> 100 || (num_slots
> 10 && optimize
== 0))
925 for (p
= temp_slots
, prev_p
= 0; p
; p
= prev_p
? prev_p
->next
: temp_slots
)
929 if (! p
->in_use
&& GET_MODE (p
->slot
) == BLKmode
)
930 for (q
= p
->next
, prev_q
= p
; q
; q
= prev_q
->next
)
933 if (! q
->in_use
&& GET_MODE (q
->slot
) == BLKmode
)
935 if (p
->base_offset
+ p
->full_size
== q
->base_offset
)
937 /* Q comes after P; combine Q into P. */
939 p
->full_size
+= q
->full_size
;
942 else if (q
->base_offset
+ q
->full_size
== p
->base_offset
)
944 /* P comes after Q; combine P into Q. */
946 q
->full_size
+= p
->full_size
;
951 /* Either delete Q or advance past it. */
953 prev_q
->next
= q
->next
;
957 /* Either delete P or advance past it. */
961 prev_p
->next
= p
->next
;
963 temp_slots
= p
->next
;
970 /* Find the temp slot corresponding to the object at address X. */
972 static struct temp_slot
*
973 find_temp_slot_from_address (rtx x
)
978 for (p
= temp_slots
; p
; p
= p
->next
)
983 else if (XEXP (p
->slot
, 0) == x
985 || (GET_CODE (x
) == PLUS
986 && XEXP (x
, 0) == virtual_stack_vars_rtx
987 && GET_CODE (XEXP (x
, 1)) == CONST_INT
988 && INTVAL (XEXP (x
, 1)) >= p
->base_offset
989 && INTVAL (XEXP (x
, 1)) < p
->base_offset
+ p
->full_size
))
992 else if (p
->address
!= 0 && GET_CODE (p
->address
) == EXPR_LIST
)
993 for (next
= p
->address
; next
; next
= XEXP (next
, 1))
994 if (XEXP (next
, 0) == x
)
998 /* If we have a sum involving a register, see if it points to a temp
1000 if (GET_CODE (x
) == PLUS
&& GET_CODE (XEXP (x
, 0)) == REG
1001 && (p
= find_temp_slot_from_address (XEXP (x
, 0))) != 0)
1003 else if (GET_CODE (x
) == PLUS
&& GET_CODE (XEXP (x
, 1)) == REG
1004 && (p
= find_temp_slot_from_address (XEXP (x
, 1))) != 0)
1010 /* Indicate that NEW is an alternate way of referring to the temp slot
1011 that previously was known by OLD. */
1014 update_temp_slot_address (rtx old
, rtx
new)
1016 struct temp_slot
*p
;
1018 if (rtx_equal_p (old
, new))
1021 p
= find_temp_slot_from_address (old
);
1023 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1024 is a register, see if one operand of the PLUS is a temporary
1025 location. If so, NEW points into it. Otherwise, if both OLD and
1026 NEW are a PLUS and if there is a register in common between them.
1027 If so, try a recursive call on those values. */
1030 if (GET_CODE (old
) != PLUS
)
1033 if (GET_CODE (new) == REG
)
1035 update_temp_slot_address (XEXP (old
, 0), new);
1036 update_temp_slot_address (XEXP (old
, 1), new);
1039 else if (GET_CODE (new) != PLUS
)
1042 if (rtx_equal_p (XEXP (old
, 0), XEXP (new, 0)))
1043 update_temp_slot_address (XEXP (old
, 1), XEXP (new, 1));
1044 else if (rtx_equal_p (XEXP (old
, 1), XEXP (new, 0)))
1045 update_temp_slot_address (XEXP (old
, 0), XEXP (new, 1));
1046 else if (rtx_equal_p (XEXP (old
, 0), XEXP (new, 1)))
1047 update_temp_slot_address (XEXP (old
, 1), XEXP (new, 0));
1048 else if (rtx_equal_p (XEXP (old
, 1), XEXP (new, 1)))
1049 update_temp_slot_address (XEXP (old
, 0), XEXP (new, 0));
1054 /* Otherwise add an alias for the temp's address. */
1055 else if (p
->address
== 0)
1059 if (GET_CODE (p
->address
) != EXPR_LIST
)
1060 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, p
->address
, NULL_RTX
);
1062 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, new, p
->address
);
1066 /* If X could be a reference to a temporary slot, mark the fact that its
1067 address was taken. */
1070 mark_temp_addr_taken (rtx x
)
1072 struct temp_slot
*p
;
1077 /* If X is not in memory or is at a constant address, it cannot be in
1078 a temporary slot. */
1079 if (GET_CODE (x
) != MEM
|| CONSTANT_P (XEXP (x
, 0)))
1082 p
= find_temp_slot_from_address (XEXP (x
, 0));
1087 /* If X could be a reference to a temporary slot, mark that slot as
1088 belonging to the to one level higher than the current level. If X
1089 matched one of our slots, just mark that one. Otherwise, we can't
1090 easily predict which it is, so upgrade all of them. Kept slots
1091 need not be touched.
1093 This is called when an ({...}) construct occurs and a statement
1094 returns a value in memory. */
1097 preserve_temp_slots (rtx x
)
1099 struct temp_slot
*p
= 0;
1101 /* If there is no result, we still might have some objects whose address
1102 were taken, so we need to make sure they stay around. */
1105 for (p
= temp_slots
; p
; p
= p
->next
)
1106 if (p
->in_use
&& p
->level
== temp_slot_level
&& p
->addr_taken
)
1112 /* If X is a register that is being used as a pointer, see if we have
1113 a temporary slot we know it points to. To be consistent with
1114 the code below, we really should preserve all non-kept slots
1115 if we can't find a match, but that seems to be much too costly. */
1116 if (GET_CODE (x
) == REG
&& REG_POINTER (x
))
1117 p
= find_temp_slot_from_address (x
);
1119 /* If X is not in memory or is at a constant address, it cannot be in
1120 a temporary slot, but it can contain something whose address was
1122 if (p
== 0 && (GET_CODE (x
) != MEM
|| CONSTANT_P (XEXP (x
, 0))))
1124 for (p
= temp_slots
; p
; p
= p
->next
)
1125 if (p
->in_use
&& p
->level
== temp_slot_level
&& p
->addr_taken
)
1131 /* First see if we can find a match. */
1133 p
= find_temp_slot_from_address (XEXP (x
, 0));
1137 /* Move everything at our level whose address was taken to our new
1138 level in case we used its address. */
1139 struct temp_slot
*q
;
1141 if (p
->level
== temp_slot_level
)
1143 for (q
= temp_slots
; q
; q
= q
->next
)
1144 if (q
!= p
&& q
->addr_taken
&& q
->level
== p
->level
)
1153 /* Otherwise, preserve all non-kept slots at this level. */
1154 for (p
= temp_slots
; p
; p
= p
->next
)
1155 if (p
->in_use
&& p
->level
== temp_slot_level
&& ! p
->keep
)
1159 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1160 with that RTL_EXPR, promote it into a temporary slot at the present
1161 level so it will not be freed when we free slots made in the
1165 preserve_rtl_expr_result (rtx x
)
1167 struct temp_slot
*p
;
1169 /* If X is not in memory or is at a constant address, it cannot be in
1170 a temporary slot. */
1171 if (x
== 0 || GET_CODE (x
) != MEM
|| CONSTANT_P (XEXP (x
, 0)))
1174 /* If we can find a match, move it to our level unless it is already at
1176 p
= find_temp_slot_from_address (XEXP (x
, 0));
1179 p
->level
= MIN (p
->level
, temp_slot_level
);
1186 /* Free all temporaries used so far. This is normally called at the end
1187 of generating code for a statement. Don't free any temporaries
1188 currently in use for an RTL_EXPR that hasn't yet been emitted.
1189 We could eventually do better than this since it can be reused while
1190 generating the same RTL_EXPR, but this is complex and probably not
1194 free_temp_slots (void)
1196 struct temp_slot
*p
;
1198 for (p
= temp_slots
; p
; p
= p
->next
)
1199 if (p
->in_use
&& p
->level
== temp_slot_level
&& ! p
->keep
1200 && p
->rtl_expr
== 0)
1203 combine_temp_slots ();
1206 /* Free all temporary slots used in T, an RTL_EXPR node. */
1209 free_temps_for_rtl_expr (tree t
)
1211 struct temp_slot
*p
;
1213 for (p
= temp_slots
; p
; p
= p
->next
)
1214 if (p
->rtl_expr
== t
)
1216 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1217 needs to be preserved. This can happen if a temporary in
1218 the RTL_EXPR was addressed; preserve_temp_slots will move
1219 the temporary into a higher level. */
1220 if (temp_slot_level
<= p
->level
)
1223 p
->rtl_expr
= NULL_TREE
;
1226 combine_temp_slots ();
1229 /* Mark all temporaries ever allocated in this function as not suitable
1230 for reuse until the current level is exited. */
1233 mark_all_temps_used (void)
1235 struct temp_slot
*p
;
1237 for (p
= temp_slots
; p
; p
= p
->next
)
1239 p
->in_use
= p
->keep
= 1;
1240 p
->level
= MIN (p
->level
, temp_slot_level
);
1244 /* Push deeper into the nesting level for stack temporaries. */
1247 push_temp_slots (void)
1252 /* Pop a temporary nesting level. All slots in use in the current level
1256 pop_temp_slots (void)
1258 struct temp_slot
*p
;
1260 for (p
= temp_slots
; p
; p
= p
->next
)
1261 if (p
->in_use
&& p
->level
== temp_slot_level
&& p
->rtl_expr
== 0)
1264 combine_temp_slots ();
1269 /* Initialize temporary slots. */
1272 init_temp_slots (void)
1274 /* We have not allocated any temporaries yet. */
1276 temp_slot_level
= 0;
1277 var_temp_slot_level
= 0;
1278 target_temp_slot_level
= 0;
1281 /* Retroactively move an auto variable from a register to a stack
1282 slot. This is done when an address-reference to the variable is
1283 seen. If RESCAN is true, all previously emitted instructions are
1284 examined and modified to handle the fact that DECL is now
1288 put_var_into_stack (tree decl
, int rescan
)
1291 enum machine_mode promoted_mode
, decl_mode
;
1292 struct function
*function
= 0;
1294 int can_use_addressof
;
1295 int volatilep
= TREE_CODE (decl
) != SAVE_EXPR
&& TREE_THIS_VOLATILE (decl
);
1296 int usedp
= (TREE_USED (decl
)
1297 || (TREE_CODE (decl
) != SAVE_EXPR
&& DECL_INITIAL (decl
) != 0));
1299 context
= decl_function_context (decl
);
1301 /* Get the current rtl used for this object and its original mode. */
1302 reg
= (TREE_CODE (decl
) == SAVE_EXPR
1303 ? SAVE_EXPR_RTL (decl
)
1304 : DECL_RTL_IF_SET (decl
));
1306 /* No need to do anything if decl has no rtx yet
1307 since in that case caller is setting TREE_ADDRESSABLE
1308 and a stack slot will be assigned when the rtl is made. */
1312 /* Get the declared mode for this object. */
1313 decl_mode
= (TREE_CODE (decl
) == SAVE_EXPR
? TYPE_MODE (TREE_TYPE (decl
))
1314 : DECL_MODE (decl
));
1315 /* Get the mode it's actually stored in. */
1316 promoted_mode
= GET_MODE (reg
);
1318 /* If this variable comes from an outer function, find that
1319 function's saved context. Don't use find_function_data here,
1320 because it might not be in any active function.
1321 FIXME: Is that really supposed to happen?
1322 It does in ObjC at least. */
1323 if (context
!= current_function_decl
&& context
!= inline_function_decl
)
1324 for (function
= outer_function_chain
; function
; function
= function
->outer
)
1325 if (function
->decl
== context
)
1328 /* If this is a variable-sized object or a structure passed by invisible
1329 reference, with a pseudo to address it, put that pseudo into the stack
1330 if the var is non-local. */
1331 if (TREE_CODE (decl
) != SAVE_EXPR
&& DECL_NONLOCAL (decl
)
1332 && GET_CODE (reg
) == MEM
1333 && GET_CODE (XEXP (reg
, 0)) == REG
1334 && REGNO (XEXP (reg
, 0)) > LAST_VIRTUAL_REGISTER
)
1336 reg
= XEXP (reg
, 0);
1337 decl_mode
= promoted_mode
= GET_MODE (reg
);
1340 /* If this variable lives in the current function and we don't need to put it
1341 in the stack for the sake of setjmp or the non-locality, try to keep it in
1342 a register until we know we actually need the address. */
1345 && ! (TREE_CODE (decl
) != SAVE_EXPR
&& DECL_NONLOCAL (decl
))
1347 /* FIXME make it work for promoted modes too */
1348 && decl_mode
== promoted_mode
1349 #ifdef NON_SAVING_SETJMP
1350 && ! (NON_SAVING_SETJMP
&& current_function_calls_setjmp
)
1354 /* If we can't use ADDRESSOF, make sure we see through one we already
1356 if (! can_use_addressof
&& GET_CODE (reg
) == MEM
1357 && GET_CODE (XEXP (reg
, 0)) == ADDRESSOF
)
1358 reg
= XEXP (XEXP (reg
, 0), 0);
1360 /* Now we should have a value that resides in one or more pseudo regs. */
1362 if (GET_CODE (reg
) == REG
)
1364 if (can_use_addressof
)
1365 gen_mem_addressof (reg
, decl
, rescan
);
1367 put_reg_into_stack (function
, reg
, TREE_TYPE (decl
), promoted_mode
,
1368 decl_mode
, volatilep
, 0, usedp
, 0);
1370 else if (GET_CODE (reg
) == CONCAT
)
1372 /* A CONCAT contains two pseudos; put them both in the stack.
1373 We do it so they end up consecutive.
1374 We fixup references to the parts only after we fixup references
1375 to the whole CONCAT, lest we do double fixups for the latter
1377 enum machine_mode part_mode
= GET_MODE (XEXP (reg
, 0));
1378 tree part_type
= lang_hooks
.types
.type_for_mode (part_mode
, 0);
1379 rtx lopart
= XEXP (reg
, 0);
1380 rtx hipart
= XEXP (reg
, 1);
1381 #ifdef FRAME_GROWS_DOWNWARD
1382 /* Since part 0 should have a lower address, do it second. */
1383 put_reg_into_stack (function
, hipart
, part_type
, part_mode
,
1384 part_mode
, volatilep
, 0, 0, 0);
1385 put_reg_into_stack (function
, lopart
, part_type
, part_mode
,
1386 part_mode
, volatilep
, 0, 0, 0);
1388 put_reg_into_stack (function
, lopart
, part_type
, part_mode
,
1389 part_mode
, volatilep
, 0, 0, 0);
1390 put_reg_into_stack (function
, hipart
, part_type
, part_mode
,
1391 part_mode
, volatilep
, 0, 0, 0);
1394 /* Change the CONCAT into a combined MEM for both parts. */
1395 PUT_CODE (reg
, MEM
);
1396 MEM_ATTRS (reg
) = 0;
1398 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1399 already computed alias sets. Here we want to re-generate. */
1401 SET_DECL_RTL (decl
, NULL
);
1402 set_mem_attributes (reg
, decl
, 1);
1404 SET_DECL_RTL (decl
, reg
);
1406 /* The two parts are in memory order already.
1407 Use the lower parts address as ours. */
1408 XEXP (reg
, 0) = XEXP (XEXP (reg
, 0), 0);
1409 /* Prevent sharing of rtl that might lose. */
1410 if (GET_CODE (XEXP (reg
, 0)) == PLUS
)
1411 XEXP (reg
, 0) = copy_rtx (XEXP (reg
, 0));
1412 if (usedp
&& rescan
)
1414 schedule_fixup_var_refs (function
, reg
, TREE_TYPE (decl
),
1416 schedule_fixup_var_refs (function
, lopart
, part_type
, part_mode
, 0);
1417 schedule_fixup_var_refs (function
, hipart
, part_type
, part_mode
, 0);
1424 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1425 into the stack frame of FUNCTION (0 means the current function).
1426 DECL_MODE is the machine mode of the user-level data type.
1427 PROMOTED_MODE is the machine mode of the register.
1428 VOLATILE_P is nonzero if this is for a "volatile" decl.
1429 USED_P is nonzero if this reg might have already been used in an insn. */
1432 put_reg_into_stack (struct function
*function
, rtx reg
, tree type
,
1433 enum machine_mode promoted_mode
,
1434 enum machine_mode decl_mode
, int volatile_p
,
1435 unsigned int original_regno
, int used_p
, htab_t ht
)
1437 struct function
*func
= function
? function
: cfun
;
1439 unsigned int regno
= original_regno
;
1442 regno
= REGNO (reg
);
1444 if (regno
< func
->x_max_parm_reg
)
1446 if (!func
->x_parm_reg_stack_loc
)
1448 new = func
->x_parm_reg_stack_loc
[regno
];
1452 new = assign_stack_local_1 (decl_mode
, GET_MODE_SIZE (decl_mode
), 0, func
);
1454 PUT_CODE (reg
, MEM
);
1455 PUT_MODE (reg
, decl_mode
);
1456 XEXP (reg
, 0) = XEXP (new, 0);
1457 MEM_ATTRS (reg
) = 0;
1458 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1459 MEM_VOLATILE_P (reg
) = volatile_p
;
1461 /* If this is a memory ref that contains aggregate components,
1462 mark it as such for cse and loop optimize. If we are reusing a
1463 previously generated stack slot, then we need to copy the bit in
1464 case it was set for other reasons. For instance, it is set for
1465 __builtin_va_alist. */
1468 MEM_SET_IN_STRUCT_P (reg
,
1469 AGGREGATE_TYPE_P (type
) || MEM_IN_STRUCT_P (new));
1470 set_mem_alias_set (reg
, get_alias_set (type
));
1474 schedule_fixup_var_refs (function
, reg
, type
, promoted_mode
, ht
);
1477 /* Make sure that all refs to the variable, previously made
1478 when it was a register, are fixed up to be valid again.
1479 See function above for meaning of arguments. */
1482 schedule_fixup_var_refs (struct function
*function
, rtx reg
, tree type
,
1483 enum machine_mode promoted_mode
, htab_t ht
)
1485 int unsigned_p
= type
? TREE_UNSIGNED (type
) : 0;
1489 struct var_refs_queue
*temp
;
1491 temp
= ggc_alloc (sizeof (struct var_refs_queue
));
1492 temp
->modified
= reg
;
1493 temp
->promoted_mode
= promoted_mode
;
1494 temp
->unsignedp
= unsigned_p
;
1495 temp
->next
= function
->fixup_var_refs_queue
;
1496 function
->fixup_var_refs_queue
= temp
;
1499 /* Variable is local; fix it up now. */
1500 fixup_var_refs (reg
, promoted_mode
, unsigned_p
, reg
, ht
);
1504 fixup_var_refs (rtx var
, enum machine_mode promoted_mode
, int unsignedp
,
1505 rtx may_share
, htab_t ht
)
1508 rtx first_insn
= get_insns ();
1509 struct sequence_stack
*stack
= seq_stack
;
1510 tree rtl_exps
= rtl_expr_chain
;
1511 int save_volatile_ok
= volatile_ok
;
1513 /* If there's a hash table, it must record all uses of VAR. */
1518 fixup_var_refs_insns_with_hash (ht
, var
, promoted_mode
, unsignedp
,
1523 /* Volatile is valid in MEMs because all we're doing in changing the
1526 fixup_var_refs_insns (first_insn
, var
, promoted_mode
, unsignedp
,
1527 stack
== 0, may_share
);
1529 /* Scan all pending sequences too. */
1530 for (; stack
; stack
= stack
->next
)
1532 push_to_full_sequence (stack
->first
, stack
->last
);
1533 fixup_var_refs_insns (stack
->first
, var
, promoted_mode
, unsignedp
,
1534 stack
->next
!= 0, may_share
);
1535 /* Update remembered end of sequence
1536 in case we added an insn at the end. */
1537 stack
->last
= get_last_insn ();
1541 /* Scan all waiting RTL_EXPRs too. */
1542 for (pending
= rtl_exps
; pending
; pending
= TREE_CHAIN (pending
))
1544 rtx seq
= RTL_EXPR_SEQUENCE (TREE_VALUE (pending
));
1545 if (seq
!= const0_rtx
&& seq
!= 0)
1547 push_to_sequence (seq
);
1548 fixup_var_refs_insns (seq
, var
, promoted_mode
, unsignedp
, 0,
1554 volatile_ok
= save_volatile_ok
;
1557 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1558 some part of an insn. Return a struct fixup_replacement whose OLD
1559 value is equal to X. Allocate a new structure if no such entry exists. */
1561 static struct fixup_replacement
*
1562 find_fixup_replacement (struct fixup_replacement
**replacements
, rtx x
)
1564 struct fixup_replacement
*p
;
1566 /* See if we have already replaced this. */
1567 for (p
= *replacements
; p
!= 0 && ! rtx_equal_p (p
->old
, x
); p
= p
->next
)
1572 p
= xmalloc (sizeof (struct fixup_replacement
));
1575 p
->next
= *replacements
;
1582 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1583 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1584 for the current function. MAY_SHARE is either a MEM that is not
1585 to be unshared or a list of them. */
1588 fixup_var_refs_insns (rtx insn
, rtx var
, enum machine_mode promoted_mode
,
1589 int unsignedp
, int toplevel
, rtx may_share
)
1593 /* fixup_var_refs_insn might modify insn, so save its next
1595 rtx next
= NEXT_INSN (insn
);
1597 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1598 the three sequences they (potentially) contain, and process
1599 them recursively. The CALL_INSN itself is not interesting. */
1601 if (GET_CODE (insn
) == CALL_INSN
1602 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
1606 /* Look at the Normal call, sibling call and tail recursion
1607 sequences attached to the CALL_PLACEHOLDER. */
1608 for (i
= 0; i
< 3; i
++)
1610 rtx seq
= XEXP (PATTERN (insn
), i
);
1613 push_to_sequence (seq
);
1614 fixup_var_refs_insns (seq
, var
, promoted_mode
, unsignedp
, 0,
1616 XEXP (PATTERN (insn
), i
) = get_insns ();
1622 else if (INSN_P (insn
))
1623 fixup_var_refs_insn (insn
, var
, promoted_mode
, unsignedp
, toplevel
,
1630 /* Look up the insns which reference VAR in HT and fix them up. Other
1631 arguments are the same as fixup_var_refs_insns.
1633 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1634 because the hash table will point straight to the interesting insn
1635 (inside the CALL_PLACEHOLDER). */
1638 fixup_var_refs_insns_with_hash (htab_t ht
, rtx var
, enum machine_mode promoted_mode
,
1639 int unsignedp
, rtx may_share
)
1641 struct insns_for_mem_entry tmp
;
1642 struct insns_for_mem_entry
*ime
;
1646 ime
= htab_find (ht
, &tmp
);
1647 for (insn_list
= ime
->insns
; insn_list
!= 0; insn_list
= XEXP (insn_list
, 1))
1648 if (INSN_P (XEXP (insn_list
, 0)))
1649 fixup_var_refs_insn (XEXP (insn_list
, 0), var
, promoted_mode
,
1650 unsignedp
, 1, may_share
);
1654 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1655 the insn under examination, VAR is the variable to fix up
1656 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1657 TOPLEVEL is nonzero if this is the main insn chain for this
1661 fixup_var_refs_insn (rtx insn
, rtx var
, enum machine_mode promoted_mode
,
1662 int unsignedp
, int toplevel
, rtx no_share
)
1665 rtx set
, prev
, prev_set
;
1668 /* Remember the notes in case we delete the insn. */
1669 note
= REG_NOTES (insn
);
1671 /* If this is a CLOBBER of VAR, delete it.
1673 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1674 and REG_RETVAL notes too. */
1675 if (GET_CODE (PATTERN (insn
)) == CLOBBER
1676 && (XEXP (PATTERN (insn
), 0) == var
1677 || (GET_CODE (XEXP (PATTERN (insn
), 0)) == CONCAT
1678 && (XEXP (XEXP (PATTERN (insn
), 0), 0) == var
1679 || XEXP (XEXP (PATTERN (insn
), 0), 1) == var
))))
1681 if ((note
= find_reg_note (insn
, REG_LIBCALL
, NULL_RTX
)) != 0)
1682 /* The REG_LIBCALL note will go away since we are going to
1683 turn INSN into a NOTE, so just delete the
1684 corresponding REG_RETVAL note. */
1685 remove_note (XEXP (note
, 0),
1686 find_reg_note (XEXP (note
, 0), REG_RETVAL
,
1692 /* The insn to load VAR from a home in the arglist
1693 is now a no-op. When we see it, just delete it.
1694 Similarly if this is storing VAR from a register from which
1695 it was loaded in the previous insn. This will occur
1696 when an ADDRESSOF was made for an arglist slot. */
1698 && (set
= single_set (insn
)) != 0
1699 && SET_DEST (set
) == var
1700 /* If this represents the result of an insn group,
1701 don't delete the insn. */
1702 && find_reg_note (insn
, REG_RETVAL
, NULL_RTX
) == 0
1703 && (rtx_equal_p (SET_SRC (set
), var
)
1704 || (GET_CODE (SET_SRC (set
)) == REG
1705 && (prev
= prev_nonnote_insn (insn
)) != 0
1706 && (prev_set
= single_set (prev
)) != 0
1707 && SET_DEST (prev_set
) == SET_SRC (set
)
1708 && rtx_equal_p (SET_SRC (prev_set
), var
))))
1714 struct fixup_replacement
*replacements
= 0;
1715 rtx next_insn
= NEXT_INSN (insn
);
1717 if (SMALL_REGISTER_CLASSES
)
1719 /* If the insn that copies the results of a CALL_INSN
1720 into a pseudo now references VAR, we have to use an
1721 intermediate pseudo since we want the life of the
1722 return value register to be only a single insn.
1724 If we don't use an intermediate pseudo, such things as
1725 address computations to make the address of VAR valid
1726 if it is not can be placed between the CALL_INSN and INSN.
1728 To make sure this doesn't happen, we record the destination
1729 of the CALL_INSN and see if the next insn uses both that
1732 if (call_dest
!= 0 && GET_CODE (insn
) == INSN
1733 && reg_mentioned_p (var
, PATTERN (insn
))
1734 && reg_mentioned_p (call_dest
, PATTERN (insn
)))
1736 rtx temp
= gen_reg_rtx (GET_MODE (call_dest
));
1738 emit_insn_before (gen_move_insn (temp
, call_dest
), insn
);
1740 PATTERN (insn
) = replace_rtx (PATTERN (insn
),
1744 if (GET_CODE (insn
) == CALL_INSN
1745 && GET_CODE (PATTERN (insn
)) == SET
)
1746 call_dest
= SET_DEST (PATTERN (insn
));
1747 else if (GET_CODE (insn
) == CALL_INSN
1748 && GET_CODE (PATTERN (insn
)) == PARALLEL
1749 && GET_CODE (XVECEXP (PATTERN (insn
), 0, 0)) == SET
)
1750 call_dest
= SET_DEST (XVECEXP (PATTERN (insn
), 0, 0));
1755 /* See if we have to do anything to INSN now that VAR is in
1756 memory. If it needs to be loaded into a pseudo, use a single
1757 pseudo for the entire insn in case there is a MATCH_DUP
1758 between two operands. We pass a pointer to the head of
1759 a list of struct fixup_replacements. If fixup_var_refs_1
1760 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1761 it will record them in this list.
1763 If it allocated a pseudo for any replacement, we copy into
1766 fixup_var_refs_1 (var
, promoted_mode
, &PATTERN (insn
), insn
,
1767 &replacements
, no_share
);
1769 /* If this is last_parm_insn, and any instructions were output
1770 after it to fix it up, then we must set last_parm_insn to
1771 the last such instruction emitted. */
1772 if (insn
== last_parm_insn
)
1773 last_parm_insn
= PREV_INSN (next_insn
);
1775 while (replacements
)
1777 struct fixup_replacement
*next
;
1779 if (GET_CODE (replacements
->new) == REG
)
1784 /* OLD might be a (subreg (mem)). */
1785 if (GET_CODE (replacements
->old
) == SUBREG
)
1787 = fixup_memory_subreg (replacements
->old
, insn
,
1791 = fixup_stack_1 (replacements
->old
, insn
);
1793 insert_before
= insn
;
1795 /* If we are changing the mode, do a conversion.
1796 This might be wasteful, but combine.c will
1797 eliminate much of the waste. */
1799 if (GET_MODE (replacements
->new)
1800 != GET_MODE (replacements
->old
))
1803 convert_move (replacements
->new,
1804 replacements
->old
, unsignedp
);
1809 seq
= gen_move_insn (replacements
->new,
1812 emit_insn_before (seq
, insert_before
);
1815 next
= replacements
->next
;
1816 free (replacements
);
1817 replacements
= next
;
1821 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1822 But don't touch other insns referred to by reg-notes;
1823 we will get them elsewhere. */
1826 if (GET_CODE (note
) != INSN_LIST
)
1828 = walk_fixup_memory_subreg (XEXP (note
, 0), insn
,
1830 note
= XEXP (note
, 1);
1834 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1835 See if the rtx expression at *LOC in INSN needs to be changed.
1837 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1838 contain a list of original rtx's and replacements. If we find that we need
1839 to modify this insn by replacing a memory reference with a pseudo or by
1840 making a new MEM to implement a SUBREG, we consult that list to see if
1841 we have already chosen a replacement. If none has already been allocated,
1842 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1843 or the SUBREG, as appropriate, to the pseudo. */
1846 fixup_var_refs_1 (rtx var
, enum machine_mode promoted_mode
, rtx
*loc
, rtx insn
,
1847 struct fixup_replacement
**replacements
, rtx no_share
)
1851 RTX_CODE code
= GET_CODE (x
);
1854 struct fixup_replacement
*replacement
;
1859 if (XEXP (x
, 0) == var
)
1861 /* Prevent sharing of rtl that might lose. */
1862 rtx sub
= copy_rtx (XEXP (var
, 0));
1864 if (! validate_change (insn
, loc
, sub
, 0))
1866 rtx y
= gen_reg_rtx (GET_MODE (sub
));
1869 /* We should be able to replace with a register or all is lost.
1870 Note that we can't use validate_change to verify this, since
1871 we're not caring for replacing all dups simultaneously. */
1872 if (! validate_replace_rtx (*loc
, y
, insn
))
1875 /* Careful! First try to recognize a direct move of the
1876 value, mimicking how things are done in gen_reload wrt
1877 PLUS. Consider what happens when insn is a conditional
1878 move instruction and addsi3 clobbers flags. */
1881 new_insn
= emit_insn (gen_rtx_SET (VOIDmode
, y
, sub
));
1885 if (recog_memoized (new_insn
) < 0)
1887 /* That failed. Fall back on force_operand and hope. */
1890 sub
= force_operand (sub
, y
);
1892 emit_insn (gen_move_insn (y
, sub
));
1898 /* Don't separate setter from user. */
1899 if (PREV_INSN (insn
) && sets_cc0_p (PREV_INSN (insn
)))
1900 insn
= PREV_INSN (insn
);
1903 emit_insn_before (seq
, insn
);
1911 /* If we already have a replacement, use it. Otherwise,
1912 try to fix up this address in case it is invalid. */
1914 replacement
= find_fixup_replacement (replacements
, var
);
1915 if (replacement
->new)
1917 *loc
= replacement
->new;
1921 *loc
= replacement
->new = x
= fixup_stack_1 (x
, insn
);
1923 /* Unless we are forcing memory to register or we changed the mode,
1924 we can leave things the way they are if the insn is valid. */
1926 INSN_CODE (insn
) = -1;
1927 if (! flag_force_mem
&& GET_MODE (x
) == promoted_mode
1928 && recog_memoized (insn
) >= 0)
1931 *loc
= replacement
->new = gen_reg_rtx (promoted_mode
);
1935 /* If X contains VAR, we need to unshare it here so that we update
1936 each occurrence separately. But all identical MEMs in one insn
1937 must be replaced with the same rtx because of the possibility of
1940 if (reg_mentioned_p (var
, x
))
1942 replacement
= find_fixup_replacement (replacements
, x
);
1943 if (replacement
->new == 0)
1944 replacement
->new = copy_most_rtx (x
, no_share
);
1946 *loc
= x
= replacement
->new;
1947 code
= GET_CODE (x
);
1964 /* Note that in some cases those types of expressions are altered
1965 by optimize_bit_field, and do not survive to get here. */
1966 if (XEXP (x
, 0) == var
1967 || (GET_CODE (XEXP (x
, 0)) == SUBREG
1968 && SUBREG_REG (XEXP (x
, 0)) == var
))
1970 /* Get TEM as a valid MEM in the mode presently in the insn.
1972 We don't worry about the possibility of MATCH_DUP here; it
1973 is highly unlikely and would be tricky to handle. */
1976 if (GET_CODE (tem
) == SUBREG
)
1978 if (GET_MODE_BITSIZE (GET_MODE (tem
))
1979 > GET_MODE_BITSIZE (GET_MODE (var
)))
1981 replacement
= find_fixup_replacement (replacements
, var
);
1982 if (replacement
->new == 0)
1983 replacement
->new = gen_reg_rtx (GET_MODE (var
));
1984 SUBREG_REG (tem
) = replacement
->new;
1986 /* The following code works only if we have a MEM, so we
1987 need to handle the subreg here. We directly substitute
1988 it assuming that a subreg must be OK here. We already
1989 scheduled a replacement to copy the mem into the
1995 tem
= fixup_memory_subreg (tem
, insn
, promoted_mode
, 0);
1998 tem
= fixup_stack_1 (tem
, insn
);
2000 /* Unless we want to load from memory, get TEM into the proper mode
2001 for an extract from memory. This can only be done if the
2002 extract is at a constant position and length. */
2004 if (! flag_force_mem
&& GET_CODE (XEXP (x
, 1)) == CONST_INT
2005 && GET_CODE (XEXP (x
, 2)) == CONST_INT
2006 && ! mode_dependent_address_p (XEXP (tem
, 0))
2007 && ! MEM_VOLATILE_P (tem
))
2009 enum machine_mode wanted_mode
= VOIDmode
;
2010 enum machine_mode is_mode
= GET_MODE (tem
);
2011 HOST_WIDE_INT pos
= INTVAL (XEXP (x
, 2));
2013 if (GET_CODE (x
) == ZERO_EXTRACT
)
2015 enum machine_mode new_mode
2016 = mode_for_extraction (EP_extzv
, 1);
2017 if (new_mode
!= MAX_MACHINE_MODE
)
2018 wanted_mode
= new_mode
;
2020 else if (GET_CODE (x
) == SIGN_EXTRACT
)
2022 enum machine_mode new_mode
2023 = mode_for_extraction (EP_extv
, 1);
2024 if (new_mode
!= MAX_MACHINE_MODE
)
2025 wanted_mode
= new_mode
;
2028 /* If we have a narrower mode, we can do something. */
2029 if (wanted_mode
!= VOIDmode
2030 && GET_MODE_SIZE (wanted_mode
) < GET_MODE_SIZE (is_mode
))
2032 HOST_WIDE_INT offset
= pos
/ BITS_PER_UNIT
;
2033 rtx old_pos
= XEXP (x
, 2);
2036 /* If the bytes and bits are counted differently, we
2037 must adjust the offset. */
2038 if (BYTES_BIG_ENDIAN
!= BITS_BIG_ENDIAN
)
2039 offset
= (GET_MODE_SIZE (is_mode
)
2040 - GET_MODE_SIZE (wanted_mode
) - offset
);
2042 pos
%= GET_MODE_BITSIZE (wanted_mode
);
2044 newmem
= adjust_address_nv (tem
, wanted_mode
, offset
);
2046 /* Make the change and see if the insn remains valid. */
2047 INSN_CODE (insn
) = -1;
2048 XEXP (x
, 0) = newmem
;
2049 XEXP (x
, 2) = GEN_INT (pos
);
2051 if (recog_memoized (insn
) >= 0)
2054 /* Otherwise, restore old position. XEXP (x, 0) will be
2056 XEXP (x
, 2) = old_pos
;
2060 /* If we get here, the bitfield extract insn can't accept a memory
2061 reference. Copy the input into a register. */
2063 tem1
= gen_reg_rtx (GET_MODE (tem
));
2064 emit_insn_before (gen_move_insn (tem1
, tem
), insn
);
2071 if (SUBREG_REG (x
) == var
)
2073 /* If this is a special SUBREG made because VAR was promoted
2074 from a wider mode, replace it with VAR and call ourself
2075 recursively, this time saying that the object previously
2076 had its current mode (by virtue of the SUBREG). */
2078 if (SUBREG_PROMOTED_VAR_P (x
))
2081 fixup_var_refs_1 (var
, GET_MODE (var
), loc
, insn
, replacements
,
2086 /* If this SUBREG makes VAR wider, it has become a paradoxical
2087 SUBREG with VAR in memory, but these aren't allowed at this
2088 stage of the compilation. So load VAR into a pseudo and take
2089 a SUBREG of that pseudo. */
2090 if (GET_MODE_SIZE (GET_MODE (x
)) > GET_MODE_SIZE (GET_MODE (var
)))
2092 replacement
= find_fixup_replacement (replacements
, var
);
2093 if (replacement
->new == 0)
2094 replacement
->new = gen_reg_rtx (promoted_mode
);
2095 SUBREG_REG (x
) = replacement
->new;
2099 /* See if we have already found a replacement for this SUBREG.
2100 If so, use it. Otherwise, make a MEM and see if the insn
2101 is recognized. If not, or if we should force MEM into a register,
2102 make a pseudo for this SUBREG. */
2103 replacement
= find_fixup_replacement (replacements
, x
);
2104 if (replacement
->new)
2106 enum machine_mode mode
= GET_MODE (x
);
2107 *loc
= replacement
->new;
2109 /* Careful! We may have just replaced a SUBREG by a MEM, which
2110 means that the insn may have become invalid again. We can't
2111 in this case make a new replacement since we already have one
2112 and we must deal with MATCH_DUPs. */
2113 if (GET_CODE (replacement
->new) == MEM
)
2115 INSN_CODE (insn
) = -1;
2116 if (recog_memoized (insn
) >= 0)
2119 fixup_var_refs_1 (replacement
->new, mode
, &PATTERN (insn
),
2120 insn
, replacements
, no_share
);
2126 replacement
->new = *loc
= fixup_memory_subreg (x
, insn
,
2129 INSN_CODE (insn
) = -1;
2130 if (! flag_force_mem
&& recog_memoized (insn
) >= 0)
2133 *loc
= replacement
->new = gen_reg_rtx (GET_MODE (x
));
2139 /* First do special simplification of bit-field references. */
2140 if (GET_CODE (SET_DEST (x
)) == SIGN_EXTRACT
2141 || GET_CODE (SET_DEST (x
)) == ZERO_EXTRACT
)
2142 optimize_bit_field (x
, insn
, 0);
2143 if (GET_CODE (SET_SRC (x
)) == SIGN_EXTRACT
2144 || GET_CODE (SET_SRC (x
)) == ZERO_EXTRACT
)
2145 optimize_bit_field (x
, insn
, 0);
2147 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2148 into a register and then store it back out. */
2149 if (GET_CODE (SET_DEST (x
)) == ZERO_EXTRACT
2150 && GET_CODE (XEXP (SET_DEST (x
), 0)) == SUBREG
2151 && SUBREG_REG (XEXP (SET_DEST (x
), 0)) == var
2152 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x
), 0)))
2153 > GET_MODE_SIZE (GET_MODE (var
))))
2155 replacement
= find_fixup_replacement (replacements
, var
);
2156 if (replacement
->new == 0)
2157 replacement
->new = gen_reg_rtx (GET_MODE (var
));
2159 SUBREG_REG (XEXP (SET_DEST (x
), 0)) = replacement
->new;
2160 emit_insn_after (gen_move_insn (var
, replacement
->new), insn
);
2163 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2164 insn into a pseudo and store the low part of the pseudo into VAR. */
2165 if (GET_CODE (SET_DEST (x
)) == SUBREG
2166 && SUBREG_REG (SET_DEST (x
)) == var
2167 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x
)))
2168 > GET_MODE_SIZE (GET_MODE (var
))))
2170 SET_DEST (x
) = tem
= gen_reg_rtx (GET_MODE (SET_DEST (x
)));
2171 emit_insn_after (gen_move_insn (var
, gen_lowpart (GET_MODE (var
),
2178 rtx dest
= SET_DEST (x
);
2179 rtx src
= SET_SRC (x
);
2180 rtx outerdest
= dest
;
2182 while (GET_CODE (dest
) == SUBREG
|| GET_CODE (dest
) == STRICT_LOW_PART
2183 || GET_CODE (dest
) == SIGN_EXTRACT
2184 || GET_CODE (dest
) == ZERO_EXTRACT
)
2185 dest
= XEXP (dest
, 0);
2187 if (GET_CODE (src
) == SUBREG
)
2188 src
= SUBREG_REG (src
);
2190 /* If VAR does not appear at the top level of the SET
2191 just scan the lower levels of the tree. */
2193 if (src
!= var
&& dest
!= var
)
2196 /* We will need to rerecognize this insn. */
2197 INSN_CODE (insn
) = -1;
2199 if (GET_CODE (outerdest
) == ZERO_EXTRACT
&& dest
== var
2200 && mode_for_extraction (EP_insv
, -1) != MAX_MACHINE_MODE
)
2202 /* Since this case will return, ensure we fixup all the
2204 fixup_var_refs_1 (var
, promoted_mode
, &XEXP (outerdest
, 1),
2205 insn
, replacements
, no_share
);
2206 fixup_var_refs_1 (var
, promoted_mode
, &XEXP (outerdest
, 2),
2207 insn
, replacements
, no_share
);
2208 fixup_var_refs_1 (var
, promoted_mode
, &SET_SRC (x
),
2209 insn
, replacements
, no_share
);
2211 tem
= XEXP (outerdest
, 0);
2213 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2214 that may appear inside a ZERO_EXTRACT.
2215 This was legitimate when the MEM was a REG. */
2216 if (GET_CODE (tem
) == SUBREG
2217 && SUBREG_REG (tem
) == var
)
2218 tem
= fixup_memory_subreg (tem
, insn
, promoted_mode
, 0);
2220 tem
= fixup_stack_1 (tem
, insn
);
2222 if (GET_CODE (XEXP (outerdest
, 1)) == CONST_INT
2223 && GET_CODE (XEXP (outerdest
, 2)) == CONST_INT
2224 && ! mode_dependent_address_p (XEXP (tem
, 0))
2225 && ! MEM_VOLATILE_P (tem
))
2227 enum machine_mode wanted_mode
;
2228 enum machine_mode is_mode
= GET_MODE (tem
);
2229 HOST_WIDE_INT pos
= INTVAL (XEXP (outerdest
, 2));
2231 wanted_mode
= mode_for_extraction (EP_insv
, 0);
2233 /* If we have a narrower mode, we can do something. */
2234 if (GET_MODE_SIZE (wanted_mode
) < GET_MODE_SIZE (is_mode
))
2236 HOST_WIDE_INT offset
= pos
/ BITS_PER_UNIT
;
2237 rtx old_pos
= XEXP (outerdest
, 2);
2240 if (BYTES_BIG_ENDIAN
!= BITS_BIG_ENDIAN
)
2241 offset
= (GET_MODE_SIZE (is_mode
)
2242 - GET_MODE_SIZE (wanted_mode
) - offset
);
2244 pos
%= GET_MODE_BITSIZE (wanted_mode
);
2246 newmem
= adjust_address_nv (tem
, wanted_mode
, offset
);
2248 /* Make the change and see if the insn remains valid. */
2249 INSN_CODE (insn
) = -1;
2250 XEXP (outerdest
, 0) = newmem
;
2251 XEXP (outerdest
, 2) = GEN_INT (pos
);
2253 if (recog_memoized (insn
) >= 0)
2256 /* Otherwise, restore old position. XEXP (x, 0) will be
2258 XEXP (outerdest
, 2) = old_pos
;
2262 /* If we get here, the bit-field store doesn't allow memory
2263 or isn't located at a constant position. Load the value into
2264 a register, do the store, and put it back into memory. */
2266 tem1
= gen_reg_rtx (GET_MODE (tem
));
2267 emit_insn_before (gen_move_insn (tem1
, tem
), insn
);
2268 emit_insn_after (gen_move_insn (tem
, tem1
), insn
);
2269 XEXP (outerdest
, 0) = tem1
;
2273 /* STRICT_LOW_PART is a no-op on memory references
2274 and it can cause combinations to be unrecognizable,
2277 if (dest
== var
&& GET_CODE (SET_DEST (x
)) == STRICT_LOW_PART
)
2278 SET_DEST (x
) = XEXP (SET_DEST (x
), 0);
2280 /* A valid insn to copy VAR into or out of a register
2281 must be left alone, to avoid an infinite loop here.
2282 If the reference to VAR is by a subreg, fix that up,
2283 since SUBREG is not valid for a memref.
2284 Also fix up the address of the stack slot.
2286 Note that we must not try to recognize the insn until
2287 after we know that we have valid addresses and no
2288 (subreg (mem ...) ...) constructs, since these interfere
2289 with determining the validity of the insn. */
2291 if ((SET_SRC (x
) == var
2292 || (GET_CODE (SET_SRC (x
)) == SUBREG
2293 && SUBREG_REG (SET_SRC (x
)) == var
))
2294 && (GET_CODE (SET_DEST (x
)) == REG
2295 || (GET_CODE (SET_DEST (x
)) == SUBREG
2296 && GET_CODE (SUBREG_REG (SET_DEST (x
))) == REG
))
2297 && GET_MODE (var
) == promoted_mode
2298 && x
== single_set (insn
))
2302 if (GET_CODE (SET_SRC (x
)) == SUBREG
2303 && (GET_MODE_SIZE (GET_MODE (SET_SRC (x
)))
2304 > GET_MODE_SIZE (GET_MODE (var
))))
2306 /* This (subreg VAR) is now a paradoxical subreg. We need
2307 to replace VAR instead of the subreg. */
2308 replacement
= find_fixup_replacement (replacements
, var
);
2309 if (replacement
->new == NULL_RTX
)
2310 replacement
->new = gen_reg_rtx (GET_MODE (var
));
2311 SUBREG_REG (SET_SRC (x
)) = replacement
->new;
2315 replacement
= find_fixup_replacement (replacements
, SET_SRC (x
));
2316 if (replacement
->new)
2317 SET_SRC (x
) = replacement
->new;
2318 else if (GET_CODE (SET_SRC (x
)) == SUBREG
)
2319 SET_SRC (x
) = replacement
->new
2320 = fixup_memory_subreg (SET_SRC (x
), insn
, promoted_mode
,
2323 SET_SRC (x
) = replacement
->new
2324 = fixup_stack_1 (SET_SRC (x
), insn
);
2327 if (recog_memoized (insn
) >= 0)
2330 /* INSN is not valid, but we know that we want to
2331 copy SET_SRC (x) to SET_DEST (x) in some way. So
2332 we generate the move and see whether it requires more
2333 than one insn. If it does, we emit those insns and
2334 delete INSN. Otherwise, we can just replace the pattern
2335 of INSN; we have already verified above that INSN has
2336 no other function that to do X. */
2338 pat
= gen_move_insn (SET_DEST (x
), SET_SRC (x
));
2339 if (NEXT_INSN (pat
) != NULL_RTX
)
2341 last
= emit_insn_before (pat
, insn
);
2343 /* INSN might have REG_RETVAL or other important notes, so
2344 we need to store the pattern of the last insn in the
2345 sequence into INSN similarly to the normal case. LAST
2346 should not have REG_NOTES, but we allow them if INSN has
2348 if (REG_NOTES (last
) && REG_NOTES (insn
))
2350 if (REG_NOTES (last
))
2351 REG_NOTES (insn
) = REG_NOTES (last
);
2352 PATTERN (insn
) = PATTERN (last
);
2357 PATTERN (insn
) = PATTERN (pat
);
2362 if ((SET_DEST (x
) == var
2363 || (GET_CODE (SET_DEST (x
)) == SUBREG
2364 && SUBREG_REG (SET_DEST (x
)) == var
))
2365 && (GET_CODE (SET_SRC (x
)) == REG
2366 || (GET_CODE (SET_SRC (x
)) == SUBREG
2367 && GET_CODE (SUBREG_REG (SET_SRC (x
))) == REG
))
2368 && GET_MODE (var
) == promoted_mode
2369 && x
== single_set (insn
))
2373 if (GET_CODE (SET_DEST (x
)) == SUBREG
)
2374 SET_DEST (x
) = fixup_memory_subreg (SET_DEST (x
), insn
,
2377 SET_DEST (x
) = fixup_stack_1 (SET_DEST (x
), insn
);
2379 if (recog_memoized (insn
) >= 0)
2382 pat
= gen_move_insn (SET_DEST (x
), SET_SRC (x
));
2383 if (NEXT_INSN (pat
) != NULL_RTX
)
2385 last
= emit_insn_before (pat
, insn
);
2387 /* INSN might have REG_RETVAL or other important notes, so
2388 we need to store the pattern of the last insn in the
2389 sequence into INSN similarly to the normal case. LAST
2390 should not have REG_NOTES, but we allow them if INSN has
2392 if (REG_NOTES (last
) && REG_NOTES (insn
))
2394 if (REG_NOTES (last
))
2395 REG_NOTES (insn
) = REG_NOTES (last
);
2396 PATTERN (insn
) = PATTERN (last
);
2401 PATTERN (insn
) = PATTERN (pat
);
2406 /* Otherwise, storing into VAR must be handled specially
2407 by storing into a temporary and copying that into VAR
2408 with a new insn after this one. Note that this case
2409 will be used when storing into a promoted scalar since
2410 the insn will now have different modes on the input
2411 and output and hence will be invalid (except for the case
2412 of setting it to a constant, which does not need any
2413 change if it is valid). We generate extra code in that case,
2414 but combine.c will eliminate it. */
2419 rtx fixeddest
= SET_DEST (x
);
2420 enum machine_mode temp_mode
;
2422 /* STRICT_LOW_PART can be discarded, around a MEM. */
2423 if (GET_CODE (fixeddest
) == STRICT_LOW_PART
)
2424 fixeddest
= XEXP (fixeddest
, 0);
2425 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2426 if (GET_CODE (fixeddest
) == SUBREG
)
2428 fixeddest
= fixup_memory_subreg (fixeddest
, insn
,
2430 temp_mode
= GET_MODE (fixeddest
);
2434 fixeddest
= fixup_stack_1 (fixeddest
, insn
);
2435 temp_mode
= promoted_mode
;
2438 temp
= gen_reg_rtx (temp_mode
);
2440 emit_insn_after (gen_move_insn (fixeddest
,
2441 gen_lowpart (GET_MODE (fixeddest
),
2445 SET_DEST (x
) = temp
;
2453 /* Nothing special about this RTX; fix its operands. */
2455 fmt
= GET_RTX_FORMAT (code
);
2456 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
2459 fixup_var_refs_1 (var
, promoted_mode
, &XEXP (x
, i
), insn
, replacements
,
2461 else if (fmt
[i
] == 'E')
2464 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2465 fixup_var_refs_1 (var
, promoted_mode
, &XVECEXP (x
, i
, j
),
2466 insn
, replacements
, no_share
);
2471 /* Previously, X had the form (SUBREG:m1 (REG:PROMOTED_MODE ...)).
2472 The REG was placed on the stack, so X now has the form (SUBREG:m1
2475 Return an rtx (MEM:m1 newaddr) which is equivalent. If any insns
2476 must be emitted to compute NEWADDR, put them before INSN.
2478 UNCRITICAL nonzero means accept paradoxical subregs.
2479 This is used for subregs found inside REG_NOTES. */
2482 fixup_memory_subreg (rtx x
, rtx insn
, enum machine_mode promoted_mode
, int uncritical
)
2485 rtx mem
= SUBREG_REG (x
);
2486 rtx addr
= XEXP (mem
, 0);
2487 enum machine_mode mode
= GET_MODE (x
);
2490 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2491 if (GET_MODE_SIZE (mode
) > GET_MODE_SIZE (GET_MODE (mem
)) && ! uncritical
)
2494 offset
= SUBREG_BYTE (x
);
2495 if (BYTES_BIG_ENDIAN
)
2496 /* If the PROMOTED_MODE is wider than the mode of the MEM, adjust
2497 the offset so that it points to the right location within the
2499 offset
-= (GET_MODE_SIZE (promoted_mode
) - GET_MODE_SIZE (GET_MODE (mem
)));
2501 if (!flag_force_addr
2502 && memory_address_p (mode
, plus_constant (addr
, offset
)))
2503 /* Shortcut if no insns need be emitted. */
2504 return adjust_address (mem
, mode
, offset
);
2507 result
= adjust_address (mem
, mode
, offset
);
2511 emit_insn_before (seq
, insn
);
2515 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2516 Replace subexpressions of X in place.
2517 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2518 Otherwise return X, with its contents possibly altered.
2520 INSN, PROMOTED_MODE and UNCRITICAL are as for
2521 fixup_memory_subreg. */
2524 walk_fixup_memory_subreg (rtx x
, rtx insn
, enum machine_mode promoted_mode
,
2534 code
= GET_CODE (x
);
2536 if (code
== SUBREG
&& GET_CODE (SUBREG_REG (x
)) == MEM
)
2537 return fixup_memory_subreg (x
, insn
, promoted_mode
, uncritical
);
2539 /* Nothing special about this RTX; fix its operands. */
2541 fmt
= GET_RTX_FORMAT (code
);
2542 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
2545 XEXP (x
, i
) = walk_fixup_memory_subreg (XEXP (x
, i
), insn
,
2546 promoted_mode
, uncritical
);
2547 else if (fmt
[i
] == 'E')
2550 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2552 = walk_fixup_memory_subreg (XVECEXP (x
, i
, j
), insn
,
2553 promoted_mode
, uncritical
);
2559 /* For each memory ref within X, if it refers to a stack slot
2560 with an out of range displacement, put the address in a temp register
2561 (emitting new insns before INSN to load these registers)
2562 and alter the memory ref to use that register.
2563 Replace each such MEM rtx with a copy, to avoid clobberage. */
2566 fixup_stack_1 (rtx x
, rtx insn
)
2569 RTX_CODE code
= GET_CODE (x
);
2574 rtx ad
= XEXP (x
, 0);
2575 /* If we have address of a stack slot but it's not valid
2576 (displacement is too large), compute the sum in a register. */
2577 if (GET_CODE (ad
) == PLUS
2578 && GET_CODE (XEXP (ad
, 0)) == REG
2579 && ((REGNO (XEXP (ad
, 0)) >= FIRST_VIRTUAL_REGISTER
2580 && REGNO (XEXP (ad
, 0)) <= LAST_VIRTUAL_REGISTER
)
2581 || REGNO (XEXP (ad
, 0)) == FRAME_POINTER_REGNUM
2582 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2583 || REGNO (XEXP (ad
, 0)) == HARD_FRAME_POINTER_REGNUM
2585 || REGNO (XEXP (ad
, 0)) == STACK_POINTER_REGNUM
2586 || REGNO (XEXP (ad
, 0)) == ARG_POINTER_REGNUM
2587 || XEXP (ad
, 0) == current_function_internal_arg_pointer
)
2588 && GET_CODE (XEXP (ad
, 1)) == CONST_INT
)
2591 if (memory_address_p (GET_MODE (x
), ad
))
2595 temp
= copy_to_reg (ad
);
2598 emit_insn_before (seq
, insn
);
2599 return replace_equiv_address (x
, temp
);
2604 fmt
= GET_RTX_FORMAT (code
);
2605 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
2608 XEXP (x
, i
) = fixup_stack_1 (XEXP (x
, i
), insn
);
2609 else if (fmt
[i
] == 'E')
2612 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
2613 XVECEXP (x
, i
, j
) = fixup_stack_1 (XVECEXP (x
, i
, j
), insn
);
2619 /* Optimization: a bit-field instruction whose field
2620 happens to be a byte or halfword in memory
2621 can be changed to a move instruction.
2623 We call here when INSN is an insn to examine or store into a bit-field.
2624 BODY is the SET-rtx to be altered.
2626 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2627 (Currently this is called only from function.c, and EQUIV_MEM
2631 optimize_bit_field (rtx body
, rtx insn
, rtx
*equiv_mem
)
2636 enum machine_mode mode
;
2638 if (GET_CODE (SET_DEST (body
)) == SIGN_EXTRACT
2639 || GET_CODE (SET_DEST (body
)) == ZERO_EXTRACT
)
2640 bitfield
= SET_DEST (body
), destflag
= 1;
2642 bitfield
= SET_SRC (body
), destflag
= 0;
2644 /* First check that the field being stored has constant size and position
2645 and is in fact a byte or halfword suitably aligned. */
2647 if (GET_CODE (XEXP (bitfield
, 1)) == CONST_INT
2648 && GET_CODE (XEXP (bitfield
, 2)) == CONST_INT
2649 && ((mode
= mode_for_size (INTVAL (XEXP (bitfield
, 1)), MODE_INT
, 1))
2651 && INTVAL (XEXP (bitfield
, 2)) % INTVAL (XEXP (bitfield
, 1)) == 0)
2655 /* Now check that the containing word is memory, not a register,
2656 and that it is safe to change the machine mode. */
2658 if (GET_CODE (XEXP (bitfield
, 0)) == MEM
)
2659 memref
= XEXP (bitfield
, 0);
2660 else if (GET_CODE (XEXP (bitfield
, 0)) == REG
2662 memref
= equiv_mem
[REGNO (XEXP (bitfield
, 0))];
2663 else if (GET_CODE (XEXP (bitfield
, 0)) == SUBREG
2664 && GET_CODE (SUBREG_REG (XEXP (bitfield
, 0))) == MEM
)
2665 memref
= SUBREG_REG (XEXP (bitfield
, 0));
2666 else if (GET_CODE (XEXP (bitfield
, 0)) == SUBREG
2668 && GET_CODE (SUBREG_REG (XEXP (bitfield
, 0))) == REG
)
2669 memref
= equiv_mem
[REGNO (SUBREG_REG (XEXP (bitfield
, 0)))];
2672 && ! mode_dependent_address_p (XEXP (memref
, 0))
2673 && ! MEM_VOLATILE_P (memref
))
2675 /* Now adjust the address, first for any subreg'ing
2676 that we are now getting rid of,
2677 and then for which byte of the word is wanted. */
2679 HOST_WIDE_INT offset
= INTVAL (XEXP (bitfield
, 2));
2682 /* Adjust OFFSET to count bits from low-address byte. */
2683 if (BITS_BIG_ENDIAN
!= BYTES_BIG_ENDIAN
)
2684 offset
= (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield
, 0)))
2685 - offset
- INTVAL (XEXP (bitfield
, 1)));
2687 /* Adjust OFFSET to count bytes from low-address byte. */
2688 offset
/= BITS_PER_UNIT
;
2689 if (GET_CODE (XEXP (bitfield
, 0)) == SUBREG
)
2691 offset
+= (SUBREG_BYTE (XEXP (bitfield
, 0))
2692 / UNITS_PER_WORD
) * UNITS_PER_WORD
;
2693 if (BYTES_BIG_ENDIAN
)
2694 offset
-= (MIN (UNITS_PER_WORD
,
2695 GET_MODE_SIZE (GET_MODE (XEXP (bitfield
, 0))))
2696 - MIN (UNITS_PER_WORD
,
2697 GET_MODE_SIZE (GET_MODE (memref
))));
2701 memref
= adjust_address (memref
, mode
, offset
);
2702 insns
= get_insns ();
2704 emit_insn_before (insns
, insn
);
2706 /* Store this memory reference where
2707 we found the bit field reference. */
2711 validate_change (insn
, &SET_DEST (body
), memref
, 1);
2712 if (! CONSTANT_ADDRESS_P (SET_SRC (body
)))
2714 rtx src
= SET_SRC (body
);
2715 while (GET_CODE (src
) == SUBREG
2716 && SUBREG_BYTE (src
) == 0)
2717 src
= SUBREG_REG (src
);
2718 if (GET_MODE (src
) != GET_MODE (memref
))
2719 src
= gen_lowpart (GET_MODE (memref
), SET_SRC (body
));
2720 validate_change (insn
, &SET_SRC (body
), src
, 1);
2722 else if (GET_MODE (SET_SRC (body
)) != VOIDmode
2723 && GET_MODE (SET_SRC (body
)) != GET_MODE (memref
))
2724 /* This shouldn't happen because anything that didn't have
2725 one of these modes should have got converted explicitly
2726 and then referenced through a subreg.
2727 This is so because the original bit-field was
2728 handled by agg_mode and so its tree structure had
2729 the same mode that memref now has. */
2734 rtx dest
= SET_DEST (body
);
2736 while (GET_CODE (dest
) == SUBREG
2737 && SUBREG_BYTE (dest
) == 0
2738 && (GET_MODE_CLASS (GET_MODE (dest
))
2739 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest
))))
2740 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest
)))
2742 dest
= SUBREG_REG (dest
);
2744 validate_change (insn
, &SET_DEST (body
), dest
, 1);
2746 if (GET_MODE (dest
) == GET_MODE (memref
))
2747 validate_change (insn
, &SET_SRC (body
), memref
, 1);
2750 /* Convert the mem ref to the destination mode. */
2751 rtx newreg
= gen_reg_rtx (GET_MODE (dest
));
2754 convert_move (newreg
, memref
,
2755 GET_CODE (SET_SRC (body
)) == ZERO_EXTRACT
);
2759 validate_change (insn
, &SET_SRC (body
), newreg
, 1);
2763 /* See if we can convert this extraction or insertion into
2764 a simple move insn. We might not be able to do so if this
2765 was, for example, part of a PARALLEL.
2767 If we succeed, write out any needed conversions. If we fail,
2768 it is hard to guess why we failed, so don't do anything
2769 special; just let the optimization be suppressed. */
2771 if (apply_change_group () && seq
)
2772 emit_insn_before (seq
, insn
);
2777 /* These routines are responsible for converting virtual register references
2778 to the actual hard register references once RTL generation is complete.
2780 The following four variables are used for communication between the
2781 routines. They contain the offsets of the virtual registers from their
2782 respective hard registers. */
2784 static int in_arg_offset
;
2785 static int var_offset
;
2786 static int dynamic_offset
;
2787 static int out_arg_offset
;
2788 static int cfa_offset
;
2790 /* In most machines, the stack pointer register is equivalent to the bottom
2793 #ifndef STACK_POINTER_OFFSET
2794 #define STACK_POINTER_OFFSET 0
2797 /* If not defined, pick an appropriate default for the offset of dynamically
2798 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2799 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2801 #ifndef STACK_DYNAMIC_OFFSET
2803 /* The bottom of the stack points to the actual arguments. If
2804 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2805 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2806 stack space for register parameters is not pushed by the caller, but
2807 rather part of the fixed stack areas and hence not included in
2808 `current_function_outgoing_args_size'. Nevertheless, we must allow
2809 for it when allocating stack dynamic objects. */
2811 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2812 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2813 ((ACCUMULATE_OUTGOING_ARGS \
2814 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2815 + (STACK_POINTER_OFFSET)) \
2818 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2819 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2820 + (STACK_POINTER_OFFSET))
2824 /* On most machines, the CFA coincides with the first incoming parm. */
2826 #ifndef ARG_POINTER_CFA_OFFSET
2827 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2830 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just
2831 had its address taken. DECL is the decl or SAVE_EXPR for the
2832 object stored in the register, for later use if we do need to force
2833 REG into the stack. REG is overwritten by the MEM like in
2834 put_reg_into_stack. RESCAN is true if previously emitted
2835 instructions must be rescanned and modified now that the REG has
2836 been transformed. */
2839 gen_mem_addressof (rtx reg
, tree decl
, int rescan
)
2841 rtx r
= gen_rtx_ADDRESSOF (Pmode
, gen_reg_rtx (GET_MODE (reg
)),
2844 /* Calculate this before we start messing with decl's RTL. */
2845 HOST_WIDE_INT set
= decl
? get_alias_set (decl
) : 0;
2847 /* If the original REG was a user-variable, then so is the REG whose
2848 address is being taken. Likewise for unchanging. */
2849 REG_USERVAR_P (XEXP (r
, 0)) = REG_USERVAR_P (reg
);
2850 RTX_UNCHANGING_P (XEXP (r
, 0)) = RTX_UNCHANGING_P (reg
);
2852 PUT_CODE (reg
, MEM
);
2853 MEM_ATTRS (reg
) = 0;
2858 tree type
= TREE_TYPE (decl
);
2859 enum machine_mode decl_mode
2860 = (DECL_P (decl
) ? DECL_MODE (decl
) : TYPE_MODE (TREE_TYPE (decl
)));
2861 rtx decl_rtl
= (TREE_CODE (decl
) == SAVE_EXPR
? SAVE_EXPR_RTL (decl
)
2862 : DECL_RTL_IF_SET (decl
));
2864 PUT_MODE (reg
, decl_mode
);
2866 /* Clear DECL_RTL momentarily so functions below will work
2867 properly, then set it again. */
2868 if (DECL_P (decl
) && decl_rtl
== reg
)
2869 SET_DECL_RTL (decl
, 0);
2871 set_mem_attributes (reg
, decl
, 1);
2872 set_mem_alias_set (reg
, set
);
2874 if (DECL_P (decl
) && decl_rtl
== reg
)
2875 SET_DECL_RTL (decl
, reg
);
2878 && (TREE_USED (decl
) || (DECL_P (decl
) && DECL_INITIAL (decl
) != 0)))
2879 fixup_var_refs (reg
, GET_MODE (reg
), TREE_UNSIGNED (type
), reg
, 0);
2883 /* This can only happen during reload. Clear the same flag bits as
2885 MEM_VOLATILE_P (reg
) = 0;
2886 RTX_UNCHANGING_P (reg
) = 0;
2887 MEM_IN_STRUCT_P (reg
) = 0;
2888 MEM_SCALAR_P (reg
) = 0;
2889 MEM_ATTRS (reg
) = 0;
2891 fixup_var_refs (reg
, GET_MODE (reg
), 0, reg
, 0);
2897 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2900 flush_addressof (tree decl
)
2902 if ((TREE_CODE (decl
) == PARM_DECL
|| TREE_CODE (decl
) == VAR_DECL
)
2903 && DECL_RTL (decl
) != 0
2904 && GET_CODE (DECL_RTL (decl
)) == MEM
2905 && GET_CODE (XEXP (DECL_RTL (decl
), 0)) == ADDRESSOF
2906 && GET_CODE (XEXP (XEXP (DECL_RTL (decl
), 0), 0)) == REG
)
2907 put_addressof_into_stack (XEXP (DECL_RTL (decl
), 0), 0);
2910 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2913 put_addressof_into_stack (rtx r
, htab_t ht
)
2916 int volatile_p
, used_p
;
2918 rtx reg
= XEXP (r
, 0);
2920 if (GET_CODE (reg
) != REG
)
2923 decl
= ADDRESSOF_DECL (r
);
2926 type
= TREE_TYPE (decl
);
2927 volatile_p
= (TREE_CODE (decl
) != SAVE_EXPR
2928 && TREE_THIS_VOLATILE (decl
));
2929 used_p
= (TREE_USED (decl
)
2930 || (DECL_P (decl
) && DECL_INITIAL (decl
) != 0));
2939 put_reg_into_stack (0, reg
, type
, GET_MODE (reg
), GET_MODE (reg
),
2940 volatile_p
, ADDRESSOF_REGNO (r
), used_p
, ht
);
2943 /* List of replacements made below in purge_addressof_1 when creating
2944 bitfield insertions. */
2945 static rtx purge_bitfield_addressof_replacements
;
2947 /* List of replacements made below in purge_addressof_1 for patterns
2948 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2949 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2950 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2951 enough in complex cases, e.g. when some field values can be
2952 extracted by usage MEM with narrower mode. */
2953 static rtx purge_addressof_replacements
;
2955 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2956 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2957 the stack. If the function returns FALSE then the replacement could not
2958 be made. If MAY_POSTPONE is true and we would not put the addressof
2959 to stack, postpone processing of the insn. */
2962 purge_addressof_1 (rtx
*loc
, rtx insn
, int force
, int store
, int may_postpone
,
2970 bool libcall
= false;
2972 /* Re-start here to avoid recursion in common cases. */
2979 /* Is this a libcall? */
2981 libcall
= REG_NOTE_KIND (*loc
) == REG_RETVAL
;
2983 code
= GET_CODE (x
);
2985 /* If we don't return in any of the cases below, we will recurse inside
2986 the RTX, which will normally result in any ADDRESSOF being forced into
2990 result
= purge_addressof_1 (&SET_DEST (x
), insn
, force
, 1,
2992 result
&= purge_addressof_1 (&SET_SRC (x
), insn
, force
, 0,
2996 else if (code
== ADDRESSOF
)
3000 if (GET_CODE (XEXP (x
, 0)) != MEM
)
3001 put_addressof_into_stack (x
, ht
);
3003 /* We must create a copy of the rtx because it was created by
3004 overwriting a REG rtx which is always shared. */
3005 sub
= copy_rtx (XEXP (XEXP (x
, 0), 0));
3006 if (validate_change (insn
, loc
, sub
, 0)
3007 || validate_replace_rtx (x
, sub
, insn
))
3012 /* If SUB is a hard or virtual register, try it as a pseudo-register.
3013 Otherwise, perhaps SUB is an expression, so generate code to compute
3015 if (GET_CODE (sub
) == REG
&& REGNO (sub
) <= LAST_VIRTUAL_REGISTER
)
3016 sub
= copy_to_reg (sub
);
3018 sub
= force_operand (sub
, NULL_RTX
);
3020 if (! validate_change (insn
, loc
, sub
, 0)
3021 && ! validate_replace_rtx (x
, sub
, insn
))
3024 insns
= get_insns ();
3026 emit_insn_before (insns
, insn
);
3030 else if (code
== MEM
&& GET_CODE (XEXP (x
, 0)) == ADDRESSOF
&& ! force
)
3032 rtx sub
= XEXP (XEXP (x
, 0), 0);
3034 if (GET_CODE (sub
) == MEM
)
3035 sub
= adjust_address_nv (sub
, GET_MODE (x
), 0);
3036 else if (GET_CODE (sub
) == REG
3037 && (MEM_VOLATILE_P (x
) || GET_MODE (x
) == BLKmode
))
3039 else if (GET_CODE (sub
) == REG
&& GET_MODE (x
) != GET_MODE (sub
))
3041 int size_x
, size_sub
;
3045 /* Postpone for now, so that we do not emit bitfield arithmetics
3046 unless there is some benefit from it. */
3047 if (!postponed_insns
|| XEXP (postponed_insns
, 0) != insn
)
3048 postponed_insns
= alloc_INSN_LIST (insn
, postponed_insns
);
3054 /* When processing REG_NOTES look at the list of
3055 replacements done on the insn to find the register that X
3059 for (tem
= purge_bitfield_addressof_replacements
;
3061 tem
= XEXP (XEXP (tem
, 1), 1))
3062 if (rtx_equal_p (x
, XEXP (tem
, 0)))
3064 *loc
= XEXP (XEXP (tem
, 1), 0);
3068 /* See comment for purge_addressof_replacements. */
3069 for (tem
= purge_addressof_replacements
;
3071 tem
= XEXP (XEXP (tem
, 1), 1))
3072 if (rtx_equal_p (XEXP (x
, 0), XEXP (tem
, 0)))
3074 rtx z
= XEXP (XEXP (tem
, 1), 0);
3076 if (GET_MODE (x
) == GET_MODE (z
)
3077 || (GET_CODE (XEXP (XEXP (tem
, 1), 0)) != REG
3078 && GET_CODE (XEXP (XEXP (tem
, 1), 0)) != SUBREG
))
3081 /* It can happen that the note may speak of things
3082 in a wider (or just different) mode than the
3083 code did. This is especially true of
3086 if (GET_CODE (z
) == SUBREG
&& SUBREG_BYTE (z
) == 0)
3089 if (GET_MODE_SIZE (GET_MODE (x
)) > UNITS_PER_WORD
3090 && (GET_MODE_SIZE (GET_MODE (x
))
3091 > GET_MODE_SIZE (GET_MODE (z
))))
3093 /* This can occur as a result in invalid
3094 pointer casts, e.g. float f; ...
3095 *(long long int *)&f.
3096 ??? We could emit a warning here, but
3097 without a line number that wouldn't be
3099 z
= gen_rtx_SUBREG (GET_MODE (x
), z
, 0);
3102 z
= gen_lowpart (GET_MODE (x
), z
);
3108 /* When we are processing the REG_NOTES of the last instruction
3109 of a libcall, there will be typically no replacements
3110 for that insn; the replacements happened before, piecemeal
3111 fashion. OTOH we are not interested in the details of
3112 this for the REG_EQUAL note, we want to know the big picture,
3113 which can be succinctly described with a simple SUBREG.
3114 Note that removing the REG_EQUAL note is not an option
3115 on the last insn of a libcall, so we must do a replacement. */
3117 /* In compile/990107-1.c:7 compiled at -O1 -m1 for sh-elf,
3119 (mem:DI (addressof:SI (reg/v:DF 160) 159 0x401c8510)
3120 [0 S8 A32]), which can be expressed with a simple
3122 if ((GET_MODE_SIZE (GET_MODE (x
))
3123 <= GET_MODE_SIZE (GET_MODE (sub
)))
3124 /* Again, invalid pointer casts (as in
3125 compile/990203-1.c) can require paradoxical
3127 || (GET_MODE_SIZE (GET_MODE (x
)) > UNITS_PER_WORD
3128 && (GET_MODE_SIZE (GET_MODE (x
))
3129 > GET_MODE_SIZE (GET_MODE (sub
)))
3132 *loc
= gen_rtx_SUBREG (GET_MODE (x
), sub
, 0);
3135 /* ??? Are there other cases we should handle? */
3137 /* Sometimes we may not be able to find the replacement. For
3138 example when the original insn was a MEM in a wider mode,
3139 and the note is part of a sign extension of a narrowed
3140 version of that MEM. Gcc testcase compile/990829-1.c can
3141 generate an example of this situation. Rather than complain
3142 we return false, which will prompt our caller to remove the
3147 size_x
= GET_MODE_BITSIZE (GET_MODE (x
));
3148 size_sub
= GET_MODE_BITSIZE (GET_MODE (sub
));
3150 /* Do not frob unchanging MEMs. If a later reference forces the
3151 pseudo to the stack, we can wind up with multiple writes to
3152 an unchanging memory, which is invalid. */
3153 if (RTX_UNCHANGING_P (x
) && size_x
!= size_sub
)
3156 /* Don't even consider working with paradoxical subregs,
3157 or the moral equivalent seen here. */
3158 else if (size_x
<= size_sub
3159 && int_mode_for_mode (GET_MODE (sub
)) != BLKmode
)
3161 /* Do a bitfield insertion to mirror what would happen
3168 rtx p
= PREV_INSN (insn
);
3171 val
= gen_reg_rtx (GET_MODE (x
));
3172 if (! validate_change (insn
, loc
, val
, 0))
3174 /* Discard the current sequence and put the
3175 ADDRESSOF on stack. */
3181 emit_insn_before (seq
, insn
);
3182 compute_insns_for_mem (p
? NEXT_INSN (p
) : get_insns (),
3186 store_bit_field (sub
, size_x
, 0, GET_MODE (x
),
3187 val
, GET_MODE_SIZE (GET_MODE (sub
)));
3189 /* Make sure to unshare any shared rtl that store_bit_field
3190 might have created. */
3191 unshare_all_rtl_again (get_insns ());
3195 p
= emit_insn_after (seq
, insn
);
3196 if (NEXT_INSN (insn
))
3197 compute_insns_for_mem (NEXT_INSN (insn
),
3198 p
? NEXT_INSN (p
) : NULL_RTX
,
3203 rtx p
= PREV_INSN (insn
);
3206 val
= extract_bit_field (sub
, size_x
, 0, 1, NULL_RTX
,
3207 GET_MODE (x
), GET_MODE (x
),
3208 GET_MODE_SIZE (GET_MODE (sub
)));
3210 if (! validate_change (insn
, loc
, val
, 0))
3212 /* Discard the current sequence and put the
3213 ADDRESSOF on stack. */
3220 emit_insn_before (seq
, insn
);
3221 compute_insns_for_mem (p
? NEXT_INSN (p
) : get_insns (),
3225 /* Remember the replacement so that the same one can be done
3226 on the REG_NOTES. */
3227 purge_bitfield_addressof_replacements
3228 = gen_rtx_EXPR_LIST (VOIDmode
, x
,
3231 purge_bitfield_addressof_replacements
));
3233 /* We replaced with a reg -- all done. */
3238 else if (validate_change (insn
, loc
, sub
, 0))
3240 /* Remember the replacement so that the same one can be done
3241 on the REG_NOTES. */
3242 if (GET_CODE (sub
) == REG
|| GET_CODE (sub
) == SUBREG
)
3246 for (tem
= purge_addressof_replacements
;
3248 tem
= XEXP (XEXP (tem
, 1), 1))
3249 if (rtx_equal_p (XEXP (x
, 0), XEXP (tem
, 0)))
3251 XEXP (XEXP (tem
, 1), 0) = sub
;
3254 purge_addressof_replacements
3255 = gen_rtx_EXPR_LIST (VOIDmode
, XEXP (x
, 0),
3256 gen_rtx_EXPR_LIST (VOIDmode
, sub
,
3257 purge_addressof_replacements
));
3265 /* Scan all subexpressions. */
3266 fmt
= GET_RTX_FORMAT (code
);
3267 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
3270 result
&= purge_addressof_1 (&XEXP (x
, i
), insn
, force
, 0,
3272 else if (*fmt
== 'E')
3273 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
3274 result
&= purge_addressof_1 (&XVECEXP (x
, i
, j
), insn
, force
, 0,
3281 /* Return a hash value for K, a REG. */
3284 insns_for_mem_hash (const void *k
)
3286 /* Use the address of the key for the hash value. */
3287 struct insns_for_mem_entry
*m
= (struct insns_for_mem_entry
*) k
;
3288 return htab_hash_pointer (m
->key
);
3291 /* Return nonzero if K1 and K2 (two REGs) are the same. */
3294 insns_for_mem_comp (const void *k1
, const void *k2
)
3296 struct insns_for_mem_entry
*m1
= (struct insns_for_mem_entry
*) k1
;
3297 struct insns_for_mem_entry
*m2
= (struct insns_for_mem_entry
*) k2
;
3298 return m1
->key
== m2
->key
;
3301 struct insns_for_mem_walk_info
3303 /* The hash table that we are using to record which INSNs use which
3307 /* The INSN we are currently processing. */
3310 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3311 to find the insns that use the REGs in the ADDRESSOFs. */
3315 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3316 that might be used in an ADDRESSOF expression, record this INSN in
3317 the hash table given by DATA (which is really a pointer to an
3318 insns_for_mem_walk_info structure). */
3321 insns_for_mem_walk (rtx
*r
, void *data
)
3323 struct insns_for_mem_walk_info
*ifmwi
3324 = (struct insns_for_mem_walk_info
*) data
;
3325 struct insns_for_mem_entry tmp
;
3326 tmp
.insns
= NULL_RTX
;
3328 if (ifmwi
->pass
== 0 && *r
&& GET_CODE (*r
) == ADDRESSOF
3329 && GET_CODE (XEXP (*r
, 0)) == REG
)
3332 tmp
.key
= XEXP (*r
, 0);
3333 e
= htab_find_slot (ifmwi
->ht
, &tmp
, INSERT
);
3336 *e
= ggc_alloc (sizeof (tmp
));
3337 memcpy (*e
, &tmp
, sizeof (tmp
));
3340 else if (ifmwi
->pass
== 1 && *r
&& GET_CODE (*r
) == REG
)
3342 struct insns_for_mem_entry
*ifme
;
3344 ifme
= htab_find (ifmwi
->ht
, &tmp
);
3346 /* If we have not already recorded this INSN, do so now. Since
3347 we process the INSNs in order, we know that if we have
3348 recorded it it must be at the front of the list. */
3349 if (ifme
&& (!ifme
->insns
|| XEXP (ifme
->insns
, 0) != ifmwi
->insn
))
3350 ifme
->insns
= gen_rtx_EXPR_LIST (VOIDmode
, ifmwi
->insn
,
3357 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3358 which REGs in HT. */
3361 compute_insns_for_mem (rtx insns
, rtx last_insn
, htab_t ht
)
3364 struct insns_for_mem_walk_info ifmwi
;
3367 for (ifmwi
.pass
= 0; ifmwi
.pass
< 2; ++ifmwi
.pass
)
3368 for (insn
= insns
; insn
!= last_insn
; insn
= NEXT_INSN (insn
))
3372 for_each_rtx (&insn
, insns_for_mem_walk
, &ifmwi
);
3376 /* Helper function for purge_addressof called through for_each_rtx.
3377 Returns true iff the rtl is an ADDRESSOF. */
3380 is_addressof (rtx
*rtl
, void *data ATTRIBUTE_UNUSED
)
3382 return GET_CODE (*rtl
) == ADDRESSOF
;
3385 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3386 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3390 purge_addressof (rtx insns
)
3395 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3396 requires a fixup pass over the instruction stream to correct
3397 INSNs that depended on the REG being a REG, and not a MEM. But,
3398 these fixup passes are slow. Furthermore, most MEMs are not
3399 mentioned in very many instructions. So, we speed up the process
3400 by pre-calculating which REGs occur in which INSNs; that allows
3401 us to perform the fixup passes much more quickly. */
3402 ht
= htab_create_ggc (1000, insns_for_mem_hash
, insns_for_mem_comp
, NULL
);
3403 compute_insns_for_mem (insns
, NULL_RTX
, ht
);
3405 postponed_insns
= NULL
;
3407 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
3410 if (! purge_addressof_1 (&PATTERN (insn
), insn
,
3411 asm_noperands (PATTERN (insn
)) > 0, 0, 1, ht
))
3412 /* If we could not replace the ADDRESSOFs in the insn,
3413 something is wrong. */
3416 if (! purge_addressof_1 (®_NOTES (insn
), NULL_RTX
, 0, 0, 0, ht
))
3418 /* If we could not replace the ADDRESSOFs in the insn's notes,
3419 we can just remove the offending notes instead. */
3422 for (note
= REG_NOTES (insn
); note
; note
= XEXP (note
, 1))
3424 /* If we find a REG_RETVAL note then the insn is a libcall.
3425 Such insns must have REG_EQUAL notes as well, in order
3426 for later passes of the compiler to work. So it is not
3427 safe to delete the notes here, and instead we abort. */
3428 if (REG_NOTE_KIND (note
) == REG_RETVAL
)
3430 if (for_each_rtx (¬e
, is_addressof
, NULL
))
3431 remove_note (insn
, note
);
3436 /* Process the postponed insns. */
3437 while (postponed_insns
)
3439 insn
= XEXP (postponed_insns
, 0);
3440 tmp
= postponed_insns
;
3441 postponed_insns
= XEXP (postponed_insns
, 1);
3442 free_INSN_LIST_node (tmp
);
3444 if (! purge_addressof_1 (&PATTERN (insn
), insn
,
3445 asm_noperands (PATTERN (insn
)) > 0, 0, 0, ht
))
3450 purge_bitfield_addressof_replacements
= 0;
3451 purge_addressof_replacements
= 0;
3453 /* REGs are shared. purge_addressof will destructively replace a REG
3454 with a MEM, which creates shared MEMs.
3456 Unfortunately, the children of put_reg_into_stack assume that MEMs
3457 referring to the same stack slot are shared (fixup_var_refs and
3458 the associated hash table code).
3460 So, we have to do another unsharing pass after we have flushed any
3461 REGs that had their address taken into the stack.
3463 It may be worth tracking whether or not we converted any REGs into
3464 MEMs to avoid this overhead when it is not needed. */
3465 unshare_all_rtl_again (get_insns ());
3468 /* Convert a SET of a hard subreg to a set of the appropriate hard
3469 register. A subroutine of purge_hard_subreg_sets. */
3472 purge_single_hard_subreg_set (rtx pattern
)
3474 rtx reg
= SET_DEST (pattern
);
3475 enum machine_mode mode
= GET_MODE (SET_DEST (pattern
));
3478 if (GET_CODE (reg
) == SUBREG
&& GET_CODE (SUBREG_REG (reg
)) == REG
3479 && REGNO (SUBREG_REG (reg
)) < FIRST_PSEUDO_REGISTER
)
3481 offset
= subreg_regno_offset (REGNO (SUBREG_REG (reg
)),
3482 GET_MODE (SUBREG_REG (reg
)),
3485 reg
= SUBREG_REG (reg
);
3489 if (GET_CODE (reg
) == REG
&& REGNO (reg
) < FIRST_PSEUDO_REGISTER
)
3491 reg
= gen_rtx_REG (mode
, REGNO (reg
) + offset
);
3492 SET_DEST (pattern
) = reg
;
3496 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3497 only such SETs that we expect to see are those left in because
3498 integrate can't handle sets of parts of a return value register.
3500 We don't use alter_subreg because we only want to eliminate subregs
3501 of hard registers. */
3504 purge_hard_subreg_sets (rtx insn
)
3506 for (; insn
; insn
= NEXT_INSN (insn
))
3510 rtx pattern
= PATTERN (insn
);
3511 switch (GET_CODE (pattern
))
3514 if (GET_CODE (SET_DEST (pattern
)) == SUBREG
)
3515 purge_single_hard_subreg_set (pattern
);
3520 for (j
= XVECLEN (pattern
, 0) - 1; j
>= 0; j
--)
3522 rtx inner_pattern
= XVECEXP (pattern
, 0, j
);
3523 if (GET_CODE (inner_pattern
) == SET
3524 && GET_CODE (SET_DEST (inner_pattern
)) == SUBREG
)
3525 purge_single_hard_subreg_set (inner_pattern
);
3536 /* Pass through the INSNS of function FNDECL and convert virtual register
3537 references to hard register references. */
3540 instantiate_virtual_regs (tree fndecl
, rtx insns
)
3545 /* Compute the offsets to use for this function. */
3546 in_arg_offset
= FIRST_PARM_OFFSET (fndecl
);
3547 var_offset
= STARTING_FRAME_OFFSET
;
3548 dynamic_offset
= STACK_DYNAMIC_OFFSET (fndecl
);
3549 out_arg_offset
= STACK_POINTER_OFFSET
;
3550 cfa_offset
= ARG_POINTER_CFA_OFFSET (fndecl
);
3552 /* Scan all variables and parameters of this function. For each that is
3553 in memory, instantiate all virtual registers if the result is a valid
3554 address. If not, we do it later. That will handle most uses of virtual
3555 regs on many machines. */
3556 instantiate_decls (fndecl
, 1);
3558 /* Initialize recognition, indicating that volatile is OK. */
3561 /* Scan through all the insns, instantiating every virtual register still
3563 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
3564 if (GET_CODE (insn
) == INSN
|| GET_CODE (insn
) == JUMP_INSN
3565 || GET_CODE (insn
) == CALL_INSN
)
3567 instantiate_virtual_regs_1 (&PATTERN (insn
), insn
, 1);
3568 if (INSN_DELETED_P (insn
))
3570 instantiate_virtual_regs_1 (®_NOTES (insn
), NULL_RTX
, 0);
3571 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3572 if (GET_CODE (insn
) == CALL_INSN
)
3573 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn
),
3576 /* Past this point all ASM statements should match. Verify that
3577 to avoid failures later in the compilation process. */
3578 if (asm_noperands (PATTERN (insn
)) >= 0
3579 && ! check_asm_operands (PATTERN (insn
)))
3580 instantiate_virtual_regs_lossage (insn
);
3583 /* Instantiate the stack slots for the parm registers, for later use in
3584 addressof elimination. */
3585 for (i
= 0; i
< max_parm_reg
; ++i
)
3586 if (parm_reg_stack_loc
[i
])
3587 instantiate_virtual_regs_1 (&parm_reg_stack_loc
[i
], NULL_RTX
, 0);
3589 /* Now instantiate the remaining register equivalences for debugging info.
3590 These will not be valid addresses. */
3591 instantiate_decls (fndecl
, 0);
3593 /* Indicate that, from now on, assign_stack_local should use
3594 frame_pointer_rtx. */
3595 virtuals_instantiated
= 1;
3598 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3599 all virtual registers in their DECL_RTL's.
3601 If VALID_ONLY, do this only if the resulting address is still valid.
3602 Otherwise, always do it. */
3605 instantiate_decls (tree fndecl
, int valid_only
)
3609 /* Process all parameters of the function. */
3610 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= TREE_CHAIN (decl
))
3612 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (decl
));
3613 HOST_WIDE_INT size_rtl
;
3615 instantiate_decl (DECL_RTL (decl
), size
, valid_only
);
3617 /* If the parameter was promoted, then the incoming RTL mode may be
3618 larger than the declared type size. We must use the larger of
3620 size_rtl
= GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl
)));
3621 size
= MAX (size_rtl
, size
);
3622 instantiate_decl (DECL_INCOMING_RTL (decl
), size
, valid_only
);
3625 /* Now process all variables defined in the function or its subblocks. */
3626 instantiate_decls_1 (DECL_INITIAL (fndecl
), valid_only
);
3629 /* Subroutine of instantiate_decls: Process all decls in the given
3630 BLOCK node and all its subblocks. */
3633 instantiate_decls_1 (tree let
, int valid_only
)
3637 for (t
= BLOCK_VARS (let
); t
; t
= TREE_CHAIN (t
))
3638 if (DECL_RTL_SET_P (t
))
3639 instantiate_decl (DECL_RTL (t
),
3640 int_size_in_bytes (TREE_TYPE (t
)),
3643 /* Process all subblocks. */
3644 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= TREE_CHAIN (t
))
3645 instantiate_decls_1 (t
, valid_only
);
3648 /* Subroutine of the preceding procedures: Given RTL representing a
3649 decl and the size of the object, do any instantiation required.
3651 If VALID_ONLY is nonzero, it means that the RTL should only be
3652 changed if the new address is valid. */
3655 instantiate_decl (rtx x
, HOST_WIDE_INT size
, int valid_only
)
3657 enum machine_mode mode
;
3660 /* If this is not a MEM, no need to do anything. Similarly if the
3661 address is a constant or a register that is not a virtual register. */
3663 if (x
== 0 || GET_CODE (x
) != MEM
)
3667 if (CONSTANT_P (addr
)
3668 || (GET_CODE (addr
) == ADDRESSOF
&& GET_CODE (XEXP (addr
, 0)) == REG
)
3669 || (GET_CODE (addr
) == REG
3670 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
3671 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
3674 /* If we should only do this if the address is valid, copy the address.
3675 We need to do this so we can undo any changes that might make the
3676 address invalid. This copy is unfortunate, but probably can't be
3680 addr
= copy_rtx (addr
);
3682 instantiate_virtual_regs_1 (&addr
, NULL_RTX
, 0);
3684 if (valid_only
&& size
>= 0)
3686 unsigned HOST_WIDE_INT decl_size
= size
;
3688 /* Now verify that the resulting address is valid for every integer or
3689 floating-point mode up to and including SIZE bytes long. We do this
3690 since the object might be accessed in any mode and frame addresses
3693 for (mode
= GET_CLASS_NARROWEST_MODE (MODE_INT
);
3694 mode
!= VOIDmode
&& GET_MODE_SIZE (mode
) <= decl_size
;
3695 mode
= GET_MODE_WIDER_MODE (mode
))
3696 if (! memory_address_p (mode
, addr
))
3699 for (mode
= GET_CLASS_NARROWEST_MODE (MODE_FLOAT
);
3700 mode
!= VOIDmode
&& GET_MODE_SIZE (mode
) <= decl_size
;
3701 mode
= GET_MODE_WIDER_MODE (mode
))
3702 if (! memory_address_p (mode
, addr
))
3706 /* Put back the address now that we have updated it and we either know
3707 it is valid or we don't care whether it is valid. */
3712 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3713 is a virtual register, return the equivalent hard register and set the
3714 offset indirectly through the pointer. Otherwise, return 0. */
3717 instantiate_new_reg (rtx x
, HOST_WIDE_INT
*poffset
)
3720 HOST_WIDE_INT offset
;
3722 if (x
== virtual_incoming_args_rtx
)
3723 new = arg_pointer_rtx
, offset
= in_arg_offset
;
3724 else if (x
== virtual_stack_vars_rtx
)
3725 new = frame_pointer_rtx
, offset
= var_offset
;
3726 else if (x
== virtual_stack_dynamic_rtx
)
3727 new = stack_pointer_rtx
, offset
= dynamic_offset
;
3728 else if (x
== virtual_outgoing_args_rtx
)
3729 new = stack_pointer_rtx
, offset
= out_arg_offset
;
3730 else if (x
== virtual_cfa_rtx
)
3731 new = arg_pointer_rtx
, offset
= cfa_offset
;
3740 /* Called when instantiate_virtual_regs has failed to update the instruction.
3741 Usually this means that non-matching instruction has been emit, however for
3742 asm statements it may be the problem in the constraints. */
3744 instantiate_virtual_regs_lossage (rtx insn
)
3746 if (asm_noperands (PATTERN (insn
)) >= 0)
3748 error_for_asm (insn
, "impossible constraint in `asm'");
3754 /* Given a pointer to a piece of rtx and an optional pointer to the
3755 containing object, instantiate any virtual registers present in it.
3757 If EXTRA_INSNS, we always do the replacement and generate
3758 any extra insns before OBJECT. If it zero, we do nothing if replacement
3761 Return 1 if we either had nothing to do or if we were able to do the
3762 needed replacement. Return 0 otherwise; we only return zero if
3763 EXTRA_INSNS is zero.
3765 We first try some simple transformations to avoid the creation of extra
3769 instantiate_virtual_regs_1 (rtx
*loc
, rtx object
, int extra_insns
)
3774 HOST_WIDE_INT offset
= 0;
3780 /* Re-start here to avoid recursion in common cases. */
3787 /* We may have detected and deleted invalid asm statements. */
3788 if (object
&& INSN_P (object
) && INSN_DELETED_P (object
))
3791 code
= GET_CODE (x
);
3793 /* Check for some special cases. */
3811 /* We are allowed to set the virtual registers. This means that
3812 the actual register should receive the source minus the
3813 appropriate offset. This is used, for example, in the handling
3814 of non-local gotos. */
3815 if ((new = instantiate_new_reg (SET_DEST (x
), &offset
)) != 0)
3817 rtx src
= SET_SRC (x
);
3819 /* We are setting the register, not using it, so the relevant
3820 offset is the negative of the offset to use were we using
3823 instantiate_virtual_regs_1 (&src
, NULL_RTX
, 0);
3825 /* The only valid sources here are PLUS or REG. Just do
3826 the simplest possible thing to handle them. */
3827 if (GET_CODE (src
) != REG
&& GET_CODE (src
) != PLUS
)
3829 instantiate_virtual_regs_lossage (object
);
3834 if (GET_CODE (src
) != REG
)
3835 temp
= force_operand (src
, NULL_RTX
);
3838 temp
= force_operand (plus_constant (temp
, offset
), NULL_RTX
);
3842 emit_insn_before (seq
, object
);
3845 if (! validate_change (object
, &SET_SRC (x
), temp
, 0)
3847 instantiate_virtual_regs_lossage (object
);
3852 instantiate_virtual_regs_1 (&SET_DEST (x
), object
, extra_insns
);
3857 /* Handle special case of virtual register plus constant. */
3858 if (CONSTANT_P (XEXP (x
, 1)))
3860 rtx old
, new_offset
;
3862 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3863 if (GET_CODE (XEXP (x
, 0)) == PLUS
)
3865 if ((new = instantiate_new_reg (XEXP (XEXP (x
, 0), 0), &offset
)))
3867 instantiate_virtual_regs_1 (&XEXP (XEXP (x
, 0), 1), object
,
3869 new = gen_rtx_PLUS (Pmode
, new, XEXP (XEXP (x
, 0), 1));
3878 #ifdef POINTERS_EXTEND_UNSIGNED
3879 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3880 we can commute the PLUS and SUBREG because pointers into the
3881 frame are well-behaved. */
3882 else if (GET_CODE (XEXP (x
, 0)) == SUBREG
&& GET_MODE (x
) == ptr_mode
3883 && GET_CODE (XEXP (x
, 1)) == CONST_INT
3885 = instantiate_new_reg (SUBREG_REG (XEXP (x
, 0)),
3887 && validate_change (object
, loc
,
3888 plus_constant (gen_lowpart (ptr_mode
,
3891 + INTVAL (XEXP (x
, 1))),
3895 else if ((new = instantiate_new_reg (XEXP (x
, 0), &offset
)) == 0)
3897 /* We know the second operand is a constant. Unless the
3898 first operand is a REG (which has been already checked),
3899 it needs to be checked. */
3900 if (GET_CODE (XEXP (x
, 0)) != REG
)
3908 new_offset
= plus_constant (XEXP (x
, 1), offset
);
3910 /* If the new constant is zero, try to replace the sum with just
3912 if (new_offset
== const0_rtx
3913 && validate_change (object
, loc
, new, 0))
3916 /* Next try to replace the register and new offset.
3917 There are two changes to validate here and we can't assume that
3918 in the case of old offset equals new just changing the register
3919 will yield a valid insn. In the interests of a little efficiency,
3920 however, we only call validate change once (we don't queue up the
3921 changes and then call apply_change_group). */
3925 ? ! validate_change (object
, &XEXP (x
, 0), new, 0)
3926 : (XEXP (x
, 0) = new,
3927 ! validate_change (object
, &XEXP (x
, 1), new_offset
, 0)))
3935 /* Otherwise copy the new constant into a register and replace
3936 constant with that register. */
3937 temp
= gen_reg_rtx (Pmode
);
3939 if (validate_change (object
, &XEXP (x
, 1), temp
, 0))
3940 emit_insn_before (gen_move_insn (temp
, new_offset
), object
);
3943 /* If that didn't work, replace this expression with a
3944 register containing the sum. */
3947 new = gen_rtx_PLUS (Pmode
, new, new_offset
);
3950 temp
= force_operand (new, NULL_RTX
);
3954 emit_insn_before (seq
, object
);
3955 if (! validate_change (object
, loc
, temp
, 0)
3956 && ! validate_replace_rtx (x
, temp
, object
))
3958 instantiate_virtual_regs_lossage (object
);
3967 /* Fall through to generic two-operand expression case. */
3973 case DIV
: case UDIV
:
3974 case MOD
: case UMOD
:
3975 case AND
: case IOR
: case XOR
:
3976 case ROTATERT
: case ROTATE
:
3977 case ASHIFTRT
: case LSHIFTRT
: case ASHIFT
:
3979 case GE
: case GT
: case GEU
: case GTU
:
3980 case LE
: case LT
: case LEU
: case LTU
:
3981 if (XEXP (x
, 1) && ! CONSTANT_P (XEXP (x
, 1)))
3982 instantiate_virtual_regs_1 (&XEXP (x
, 1), object
, extra_insns
);
3987 /* Most cases of MEM that convert to valid addresses have already been
3988 handled by our scan of decls. The only special handling we
3989 need here is to make a copy of the rtx to ensure it isn't being
3990 shared if we have to change it to a pseudo.
3992 If the rtx is a simple reference to an address via a virtual register,
3993 it can potentially be shared. In such cases, first try to make it
3994 a valid address, which can also be shared. Otherwise, copy it and
3997 First check for common cases that need no processing. These are
3998 usually due to instantiation already being done on a previous instance
4002 if (CONSTANT_ADDRESS_P (temp
)
4003 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4004 || temp
== arg_pointer_rtx
4006 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4007 || temp
== hard_frame_pointer_rtx
4009 || temp
== frame_pointer_rtx
)
4012 if (GET_CODE (temp
) == PLUS
4013 && CONSTANT_ADDRESS_P (XEXP (temp
, 1))
4014 && (XEXP (temp
, 0) == frame_pointer_rtx
4015 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4016 || XEXP (temp
, 0) == hard_frame_pointer_rtx
4018 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4019 || XEXP (temp
, 0) == arg_pointer_rtx
4024 if (temp
== virtual_stack_vars_rtx
4025 || temp
== virtual_incoming_args_rtx
4026 || (GET_CODE (temp
) == PLUS
4027 && CONSTANT_ADDRESS_P (XEXP (temp
, 1))
4028 && (XEXP (temp
, 0) == virtual_stack_vars_rtx
4029 || XEXP (temp
, 0) == virtual_incoming_args_rtx
)))
4031 /* This MEM may be shared. If the substitution can be done without
4032 the need to generate new pseudos, we want to do it in place
4033 so all copies of the shared rtx benefit. The call below will
4034 only make substitutions if the resulting address is still
4037 Note that we cannot pass X as the object in the recursive call
4038 since the insn being processed may not allow all valid
4039 addresses. However, if we were not passed on object, we can
4040 only modify X without copying it if X will have a valid
4043 ??? Also note that this can still lose if OBJECT is an insn that
4044 has less restrictions on an address that some other insn.
4045 In that case, we will modify the shared address. This case
4046 doesn't seem very likely, though. One case where this could
4047 happen is in the case of a USE or CLOBBER reference, but we
4048 take care of that below. */
4050 if (instantiate_virtual_regs_1 (&XEXP (x
, 0),
4051 object
? object
: x
, 0))
4054 /* Otherwise make a copy and process that copy. We copy the entire
4055 RTL expression since it might be a PLUS which could also be
4057 *loc
= x
= copy_rtx (x
);
4060 /* Fall through to generic unary operation case. */
4063 case STRICT_LOW_PART
:
4065 case PRE_DEC
: case PRE_INC
: case POST_DEC
: case POST_INC
:
4066 case SIGN_EXTEND
: case ZERO_EXTEND
:
4067 case TRUNCATE
: case FLOAT_EXTEND
: case FLOAT_TRUNCATE
:
4068 case FLOAT
: case FIX
:
4069 case UNSIGNED_FIX
: case UNSIGNED_FLOAT
:
4074 case POPCOUNT
: case PARITY
:
4075 /* These case either have just one operand or we know that we need not
4076 check the rest of the operands. */
4082 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4083 go ahead and make the invalid one, but do it to a copy. For a REG,
4084 just make the recursive call, since there's no chance of a problem. */
4086 if ((GET_CODE (XEXP (x
, 0)) == MEM
4087 && instantiate_virtual_regs_1 (&XEXP (XEXP (x
, 0), 0), XEXP (x
, 0),
4089 || (GET_CODE (XEXP (x
, 0)) == REG
4090 && instantiate_virtual_regs_1 (&XEXP (x
, 0), object
, 0)))
4093 XEXP (x
, 0) = copy_rtx (XEXP (x
, 0));
4098 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4099 in front of this insn and substitute the temporary. */
4100 if ((new = instantiate_new_reg (x
, &offset
)) != 0)
4102 temp
= plus_constant (new, offset
);
4103 if (!validate_change (object
, loc
, temp
, 0))
4109 temp
= force_operand (temp
, NULL_RTX
);
4113 emit_insn_before (seq
, object
);
4114 if (! validate_change (object
, loc
, temp
, 0)
4115 && ! validate_replace_rtx (x
, temp
, object
))
4116 instantiate_virtual_regs_lossage (object
);
4123 if (GET_CODE (XEXP (x
, 0)) == REG
)
4126 else if (GET_CODE (XEXP (x
, 0)) == MEM
)
4128 /* If we have a (addressof (mem ..)), do any instantiation inside
4129 since we know we'll be making the inside valid when we finally
4130 remove the ADDRESSOF. */
4131 instantiate_virtual_regs_1 (&XEXP (XEXP (x
, 0), 0), NULL_RTX
, 0);
4140 /* Scan all subexpressions. */
4141 fmt
= GET_RTX_FORMAT (code
);
4142 for (i
= 0; i
< GET_RTX_LENGTH (code
); i
++, fmt
++)
4145 if (!instantiate_virtual_regs_1 (&XEXP (x
, i
), object
, extra_insns
))
4148 else if (*fmt
== 'E')
4149 for (j
= 0; j
< XVECLEN (x
, i
); j
++)
4150 if (! instantiate_virtual_regs_1 (&XVECEXP (x
, i
, j
), object
,
4157 /* Optimization: assuming this function does not receive nonlocal gotos,
4158 delete the handlers for such, as well as the insns to establish
4159 and disestablish them. */
4162 delete_handlers (void)
4165 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4167 /* Delete the handler by turning off the flag that would
4168 prevent jump_optimize from deleting it.
4169 Also permit deletion of the nonlocal labels themselves
4170 if nothing local refers to them. */
4171 if (GET_CODE (insn
) == CODE_LABEL
)
4175 LABEL_PRESERVE_P (insn
) = 0;
4177 /* Remove it from the nonlocal_label list, to avoid confusing
4179 for (t
= nonlocal_labels
, last_t
= 0; t
;
4180 last_t
= t
, t
= TREE_CHAIN (t
))
4181 if (DECL_RTL (TREE_VALUE (t
)) == insn
)
4186 nonlocal_labels
= TREE_CHAIN (nonlocal_labels
);
4188 TREE_CHAIN (last_t
) = TREE_CHAIN (t
);
4191 if (GET_CODE (insn
) == INSN
)
4195 for (t
= nonlocal_goto_handler_slots
; t
!= 0; t
= XEXP (t
, 1))
4196 if (reg_mentioned_p (t
, PATTERN (insn
)))
4202 || (nonlocal_goto_stack_level
!= 0
4203 && reg_mentioned_p (nonlocal_goto_stack_level
,
4205 delete_related_insns (insn
);
4210 /* Return the first insn following those generated by `assign_parms'. */
4213 get_first_nonparm_insn (void)
4216 return NEXT_INSN (last_parm_insn
);
4217 return get_insns ();
4220 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4221 This means a type for which function calls must pass an address to the
4222 function or get an address back from the function.
4223 EXP may be a type node or an expression (whose type is tested). */
4226 aggregate_value_p (tree exp
, tree fntype
)
4228 int i
, regno
, nregs
;
4231 tree type
= (TYPE_P (exp
)) ? exp
: TREE_TYPE (exp
);
4234 switch (TREE_CODE (fntype
))
4237 fntype
= get_callee_fndecl (fntype
);
4238 fntype
= fntype
? TREE_TYPE (fntype
) : 0;
4241 fntype
= TREE_TYPE (fntype
);
4246 case IDENTIFIER_NODE
:
4250 /* We don't expect other rtl types here. */
4254 if (TREE_CODE (type
) == VOID_TYPE
)
4256 if (targetm
.calls
.return_in_memory (type
, fntype
))
4258 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4259 and thus can't be returned in registers. */
4260 if (TREE_ADDRESSABLE (type
))
4262 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
4264 /* Make sure we have suitable call-clobbered regs to return
4265 the value in; if not, we must return it in memory. */
4266 reg
= hard_function_value (type
, 0, 0);
4268 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4270 if (GET_CODE (reg
) != REG
)
4273 regno
= REGNO (reg
);
4274 nregs
= hard_regno_nregs
[regno
][TYPE_MODE (type
)];
4275 for (i
= 0; i
< nregs
; i
++)
4276 if (! call_used_regs
[regno
+ i
])
4281 /* Assign RTL expressions to the function's parameters.
4282 This may involve copying them into registers and using
4283 those registers as the RTL for them. */
4286 assign_parms (tree fndecl
)
4289 CUMULATIVE_ARGS args_so_far
;
4290 /* Total space needed so far for args on the stack,
4291 given as a constant and a tree-expression. */
4292 struct args_size stack_args_size
;
4293 HOST_WIDE_INT extra_pretend_bytes
= 0;
4294 tree fntype
= TREE_TYPE (fndecl
);
4295 tree fnargs
= DECL_ARGUMENTS (fndecl
), orig_fnargs
;
4296 /* This is used for the arg pointer when referring to stack args. */
4297 rtx internal_arg_pointer
;
4298 /* This is a dummy PARM_DECL that we used for the function result if
4299 the function returns a structure. */
4300 tree function_result_decl
= 0;
4301 int varargs_setup
= 0;
4302 int reg_parm_stack_space ATTRIBUTE_UNUSED
= 0;
4303 rtx conversion_insns
= 0;
4305 /* Nonzero if function takes extra anonymous args.
4306 This means the last named arg must be on the stack
4307 right before the anonymous ones. */
4309 = (TYPE_ARG_TYPES (fntype
) != 0
4310 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype
)))
4311 != void_type_node
));
4313 current_function_stdarg
= stdarg
;
4315 /* If the reg that the virtual arg pointer will be translated into is
4316 not a fixed reg or is the stack pointer, make a copy of the virtual
4317 arg pointer, and address parms via the copy. The frame pointer is
4318 considered fixed even though it is not marked as such.
4320 The second time through, simply use ap to avoid generating rtx. */
4322 if ((ARG_POINTER_REGNUM
== STACK_POINTER_REGNUM
4323 || ! (fixed_regs
[ARG_POINTER_REGNUM
]
4324 || ARG_POINTER_REGNUM
== FRAME_POINTER_REGNUM
)))
4325 internal_arg_pointer
= copy_to_reg (virtual_incoming_args_rtx
);
4327 internal_arg_pointer
= virtual_incoming_args_rtx
;
4328 current_function_internal_arg_pointer
= internal_arg_pointer
;
4330 stack_args_size
.constant
= 0;
4331 stack_args_size
.var
= 0;
4333 /* If struct value address is treated as the first argument, make it so. */
4334 if (aggregate_value_p (DECL_RESULT (fndecl
), fndecl
)
4335 && ! current_function_returns_pcc_struct
4336 && targetm
.calls
.struct_value_rtx (TREE_TYPE (fndecl
), 1) == 0)
4338 tree type
= build_pointer_type (TREE_TYPE (fntype
));
4340 function_result_decl
= build_decl (PARM_DECL
, NULL_TREE
, type
);
4342 DECL_ARG_TYPE (function_result_decl
) = type
;
4343 TREE_CHAIN (function_result_decl
) = fnargs
;
4344 fnargs
= function_result_decl
;
4347 orig_fnargs
= fnargs
;
4349 max_parm_reg
= LAST_VIRTUAL_REGISTER
+ 1;
4350 parm_reg_stack_loc
= ggc_alloc_cleared (max_parm_reg
* sizeof (rtx
));
4352 /* If the target wants to split complex arguments into scalars, do so. */
4353 if (targetm
.calls
.split_complex_arg
)
4354 fnargs
= split_complex_args (fnargs
);
4356 #ifdef REG_PARM_STACK_SPACE
4357 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
4360 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4361 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far
, fntype
, NULL_RTX
);
4363 INIT_CUMULATIVE_ARGS (args_so_far
, fntype
, NULL_RTX
, fndecl
, -1);
4366 /* We haven't yet found an argument that we must push and pretend the
4368 current_function_pretend_args_size
= 0;
4370 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
4374 enum machine_mode promoted_mode
, passed_mode
;
4375 enum machine_mode nominal_mode
, promoted_nominal_mode
;
4377 struct locate_and_pad_arg_data locate
;
4378 int passed_pointer
= 0;
4379 int did_conversion
= 0;
4380 tree passed_type
= DECL_ARG_TYPE (parm
);
4381 tree nominal_type
= TREE_TYPE (parm
);
4382 int last_named
= 0, named_arg
;
4385 int pretend_bytes
= 0;
4386 int loaded_in_reg
= 0;
4388 /* Set LAST_NAMED if this is last named arg before last
4394 for (tem
= TREE_CHAIN (parm
); tem
; tem
= TREE_CHAIN (tem
))
4395 if (DECL_NAME (tem
))
4401 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4402 most machines, if this is a varargs/stdarg function, then we treat
4403 the last named arg as if it were anonymous too. */
4404 named_arg
= (targetm
.calls
.strict_argument_naming (&args_so_far
)
4407 if (TREE_TYPE (parm
) == error_mark_node
4408 /* This can happen after weird syntax errors
4409 or if an enum type is defined among the parms. */
4410 || TREE_CODE (parm
) != PARM_DECL
4411 || passed_type
== NULL
)
4413 SET_DECL_RTL (parm
, gen_rtx_MEM (BLKmode
, const0_rtx
));
4414 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
);
4415 TREE_USED (parm
) = 1;
4419 /* Find mode of arg as it is passed, and mode of arg
4420 as it should be during execution of this function. */
4421 passed_mode
= TYPE_MODE (passed_type
);
4422 nominal_mode
= TYPE_MODE (nominal_type
);
4424 /* If the parm's mode is VOID, its value doesn't matter,
4425 and avoid the usual things like emit_move_insn that could crash. */
4426 if (nominal_mode
== VOIDmode
)
4428 SET_DECL_RTL (parm
, const0_rtx
);
4429 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
);
4433 /* If the parm is to be passed as a transparent union, use the
4434 type of the first field for the tests below. We have already
4435 verified that the modes are the same. */
4436 if (DECL_TRANSPARENT_UNION (parm
)
4437 || (TREE_CODE (passed_type
) == UNION_TYPE
4438 && TYPE_TRANSPARENT_UNION (passed_type
)))
4439 passed_type
= TREE_TYPE (TYPE_FIELDS (passed_type
));
4441 /* See if this arg was passed by invisible reference. It is if
4442 it is an object whose size depends on the contents of the
4443 object itself or if the machine requires these objects be passed
4446 if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (passed_type
))
4447 || TREE_ADDRESSABLE (passed_type
)
4448 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4449 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far
, passed_mode
,
4450 passed_type
, named_arg
)
4454 passed_type
= nominal_type
= build_pointer_type (passed_type
);
4456 passed_mode
= nominal_mode
= Pmode
;
4458 /* See if the frontend wants to pass this by invisible reference. */
4459 else if (passed_type
!= nominal_type
4460 && POINTER_TYPE_P (passed_type
)
4461 && TREE_TYPE (passed_type
) == nominal_type
)
4463 nominal_type
= passed_type
;
4465 passed_mode
= nominal_mode
= Pmode
;
4468 promoted_mode
= passed_mode
;
4470 if (targetm
.calls
.promote_function_args (TREE_TYPE (fndecl
)))
4472 /* Compute the mode in which the arg is actually extended to. */
4473 unsignedp
= TREE_UNSIGNED (passed_type
);
4474 promoted_mode
= promote_mode (passed_type
, promoted_mode
, &unsignedp
, 1);
4477 /* Let machine desc say which reg (if any) the parm arrives in.
4478 0 means it arrives on the stack. */
4479 #ifdef FUNCTION_INCOMING_ARG
4480 entry_parm
= FUNCTION_INCOMING_ARG (args_so_far
, promoted_mode
,
4481 passed_type
, named_arg
);
4483 entry_parm
= FUNCTION_ARG (args_so_far
, promoted_mode
,
4484 passed_type
, named_arg
);
4487 if (entry_parm
== 0)
4488 promoted_mode
= passed_mode
;
4490 /* If this is the last named parameter, do any required setup for
4491 varargs or stdargs. We need to know about the case of this being an
4492 addressable type, in which case we skip the registers it
4493 would have arrived in.
4495 For stdargs, LAST_NAMED will be set for two parameters, the one that
4496 is actually the last named, and the dummy parameter. We only
4497 want to do this action once.
4499 Also, indicate when RTL generation is to be suppressed. */
4500 if (last_named
&& !varargs_setup
)
4502 int varargs_pretend_bytes
= 0;
4503 targetm
.calls
.setup_incoming_varargs (&args_so_far
, promoted_mode
,
4505 &varargs_pretend_bytes
, 0);
4508 /* If the back-end has requested extra stack space, record how
4509 much is needed. Do not change pretend_args_size otherwise
4510 since it may be nonzero from an earlier partial argument. */
4511 if (varargs_pretend_bytes
> 0)
4512 current_function_pretend_args_size
= varargs_pretend_bytes
;
4515 /* Determine parm's home in the stack,
4516 in case it arrives in the stack or we should pretend it did.
4518 Compute the stack position and rtx where the argument arrives
4521 There is one complexity here: If this was a parameter that would
4522 have been passed in registers, but wasn't only because it is
4523 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4524 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4525 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4526 0 as it was the previous time. */
4527 in_regs
= entry_parm
!= 0;
4528 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4531 if (!in_regs
&& !named_arg
)
4534 targetm
.calls
.pretend_outgoing_varargs_named (&args_so_far
);
4537 #ifdef FUNCTION_INCOMING_ARG
4538 in_regs
= FUNCTION_INCOMING_ARG (args_so_far
, promoted_mode
,
4540 pretend_named
) != 0;
4542 in_regs
= FUNCTION_ARG (args_so_far
, promoted_mode
,
4544 pretend_named
) != 0;
4549 /* If this parameter was passed both in registers and in the stack,
4550 use the copy on the stack. */
4551 if (MUST_PASS_IN_STACK (promoted_mode
, passed_type
))
4554 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4557 partial
= FUNCTION_ARG_PARTIAL_NREGS (args_so_far
, promoted_mode
,
4558 passed_type
, named_arg
);
4560 /* The caller might already have allocated stack space
4561 for the register parameters. */
4562 && reg_parm_stack_space
== 0)
4564 /* Part of this argument is passed in registers and part
4565 is passed on the stack. Ask the prologue code to extend
4566 the stack part so that we can recreate the full value.
4568 PRETEND_BYTES is the size of the registers we need to store.
4569 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
4570 stack space that the prologue should allocate.
4572 Internally, gcc assumes that the argument pointer is
4573 aligned to STACK_BOUNDARY bits. This is used both for
4574 alignment optimizations (see init_emit) and to locate
4575 arguments that are aligned to more than PARM_BOUNDARY
4576 bits. We must preserve this invariant by rounding
4577 CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to a stack
4580 /* We assume at most one partial arg, and it must be the first
4581 argument on the stack. */
4582 if (extra_pretend_bytes
|| current_function_pretend_args_size
)
4585 pretend_bytes
= partial
* UNITS_PER_WORD
;
4586 current_function_pretend_args_size
4587 = CEIL_ROUND (pretend_bytes
, STACK_BYTES
);
4589 /* We want to align relative to the actual stack pointer, so
4590 don't include this in the stack size until later. */
4591 extra_pretend_bytes
= current_function_pretend_args_size
;
4596 memset (&locate
, 0, sizeof (locate
));
4597 locate_and_pad_parm (promoted_mode
, passed_type
, in_regs
,
4598 entry_parm
? partial
: 0, fndecl
,
4599 &stack_args_size
, &locate
);
4600 /* Adjust offsets to include the pretend args. */
4601 locate
.slot_offset
.constant
+= extra_pretend_bytes
- pretend_bytes
;
4602 locate
.offset
.constant
+= extra_pretend_bytes
- pretend_bytes
;
4607 /* If we're passing this arg using a reg, make its stack home
4608 the aligned stack slot. */
4610 offset_rtx
= ARGS_SIZE_RTX (locate
.slot_offset
);
4612 offset_rtx
= ARGS_SIZE_RTX (locate
.offset
);
4614 if (offset_rtx
== const0_rtx
)
4615 stack_parm
= gen_rtx_MEM (promoted_mode
, internal_arg_pointer
);
4617 stack_parm
= gen_rtx_MEM (promoted_mode
,
4618 gen_rtx_PLUS (Pmode
,
4619 internal_arg_pointer
,
4622 set_mem_attributes (stack_parm
, parm
, 1);
4623 if (entry_parm
&& MEM_ATTRS (stack_parm
)->align
< PARM_BOUNDARY
)
4624 set_mem_align (stack_parm
, PARM_BOUNDARY
);
4626 /* Set also REG_ATTRS if parameter was passed in a register. */
4628 set_reg_attrs_for_parm (entry_parm
, stack_parm
);
4631 /* If this parm was passed part in regs and part in memory,
4632 pretend it arrived entirely in memory
4633 by pushing the register-part onto the stack.
4635 In the special case of a DImode or DFmode that is split,
4636 we could put it together in a pseudoreg directly,
4637 but for now that's not worth bothering with. */
4641 /* Handle calls that pass values in multiple non-contiguous
4642 locations. The Irix 6 ABI has examples of this. */
4643 if (GET_CODE (entry_parm
) == PARALLEL
)
4644 emit_group_store (validize_mem (stack_parm
), entry_parm
,
4646 int_size_in_bytes (TREE_TYPE (parm
)));
4649 move_block_from_reg (REGNO (entry_parm
), validize_mem (stack_parm
),
4652 entry_parm
= stack_parm
;
4655 /* If we didn't decide this parm came in a register,
4656 by default it came on the stack. */
4657 if (entry_parm
== 0)
4658 entry_parm
= stack_parm
;
4660 /* Record permanently how this parm was passed. */
4661 set_decl_incoming_rtl (parm
, entry_parm
);
4663 /* If there is actually space on the stack for this parm,
4664 count it in stack_args_size; otherwise set stack_parm to 0
4665 to indicate there is no preallocated stack slot for the parm. */
4667 if (entry_parm
== stack_parm
4668 || (GET_CODE (entry_parm
) == PARALLEL
4669 && XEXP (XVECEXP (entry_parm
, 0, 0), 0) == NULL_RTX
)
4670 #if defined (REG_PARM_STACK_SPACE)
4671 /* On some machines, even if a parm value arrives in a register
4672 there is still an (uninitialized) stack slot allocated
4674 || REG_PARM_STACK_SPACE (fndecl
) > 0
4678 stack_args_size
.constant
+= locate
.size
.constant
;
4679 if (locate
.size
.var
)
4680 ADD_PARM_SIZE (stack_args_size
, locate
.size
.var
);
4683 /* No stack slot was pushed for this parm. */
4686 /* Update info on where next arg arrives in registers. */
4688 FUNCTION_ARG_ADVANCE (args_so_far
, promoted_mode
,
4689 passed_type
, named_arg
);
4691 /* If we can't trust the parm stack slot to be aligned enough
4692 for its ultimate type, don't use that slot after entry.
4693 We'll make another stack slot, if we need one. */
4695 unsigned int thisparm_boundary
4696 = FUNCTION_ARG_BOUNDARY (promoted_mode
, passed_type
);
4698 if (GET_MODE_ALIGNMENT (nominal_mode
) > thisparm_boundary
)
4702 /* If parm was passed in memory, and we need to convert it on entry,
4703 don't store it back in that same slot. */
4704 if (entry_parm
== stack_parm
4705 && nominal_mode
!= BLKmode
&& nominal_mode
!= passed_mode
)
4708 /* When an argument is passed in multiple locations, we can't
4709 make use of this information, but we can save some copying if
4710 the whole argument is passed in a single register. */
4711 if (GET_CODE (entry_parm
) == PARALLEL
4712 && nominal_mode
!= BLKmode
&& passed_mode
!= BLKmode
)
4714 int i
, len
= XVECLEN (entry_parm
, 0);
4716 for (i
= 0; i
< len
; i
++)
4717 if (XEXP (XVECEXP (entry_parm
, 0, i
), 0) != NULL_RTX
4718 && GET_CODE (XEXP (XVECEXP (entry_parm
, 0, i
), 0)) == REG
4719 && (GET_MODE (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
4721 && INTVAL (XEXP (XVECEXP (entry_parm
, 0, i
), 1)) == 0)
4723 entry_parm
= XEXP (XVECEXP (entry_parm
, 0, i
), 0);
4724 set_decl_incoming_rtl (parm
, entry_parm
);
4729 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4730 in the mode in which it arrives.
4731 STACK_PARM is an RTX for a stack slot where the parameter can live
4732 during the function (in case we want to put it there).
4733 STACK_PARM is 0 if no stack slot was pushed for it.
4735 Now output code if necessary to convert ENTRY_PARM to
4736 the type in which this function declares it,
4737 and store that result in an appropriate place,
4738 which may be a pseudo reg, may be STACK_PARM,
4739 or may be a local stack slot if STACK_PARM is 0.
4741 Set DECL_RTL to that place. */
4743 if (GET_CODE (entry_parm
) == PARALLEL
&& nominal_mode
!= BLKmode
4744 && XVECLEN (entry_parm
, 0) > 1)
4746 /* Reconstitute objects the size of a register or larger using
4747 register operations instead of the stack. */
4748 rtx parmreg
= gen_reg_rtx (nominal_mode
);
4750 if (REG_P (parmreg
))
4752 unsigned int regno
= REGNO (parmreg
);
4754 emit_group_store (parmreg
, entry_parm
, TREE_TYPE (parm
),
4755 int_size_in_bytes (TREE_TYPE (parm
)));
4756 SET_DECL_RTL (parm
, parmreg
);
4759 if (regno
>= max_parm_reg
)
4762 int old_max_parm_reg
= max_parm_reg
;
4764 /* It's slow to expand this one register at a time,
4765 but it's also rare and we need max_parm_reg to be
4766 precisely correct. */
4767 max_parm_reg
= regno
+ 1;
4768 new = ggc_realloc (parm_reg_stack_loc
,
4769 max_parm_reg
* sizeof (rtx
));
4770 memset (new + old_max_parm_reg
, 0,
4771 (max_parm_reg
- old_max_parm_reg
) * sizeof (rtx
));
4772 parm_reg_stack_loc
= new;
4773 parm_reg_stack_loc
[regno
] = stack_parm
;
4778 if (nominal_mode
== BLKmode
4779 #ifdef BLOCK_REG_PADDING
4780 || (locate
.where_pad
== (BYTES_BIG_ENDIAN
? upward
: downward
)
4781 && GET_MODE_SIZE (promoted_mode
) < UNITS_PER_WORD
)
4783 || GET_CODE (entry_parm
) == PARALLEL
)
4785 /* If a BLKmode arrives in registers, copy it to a stack slot.
4786 Handle calls that pass values in multiple non-contiguous
4787 locations. The Irix 6 ABI has examples of this. */
4788 if (GET_CODE (entry_parm
) == REG
4789 || (GET_CODE (entry_parm
) == PARALLEL
4790 && (!loaded_in_reg
|| !optimize
)))
4792 int size
= int_size_in_bytes (TREE_TYPE (parm
));
4793 int size_stored
= CEIL_ROUND (size
, UNITS_PER_WORD
);
4796 /* Note that we will be storing an integral number of words.
4797 So we have to be careful to ensure that we allocate an
4798 integral number of words. We do this below in the
4799 assign_stack_local if space was not allocated in the argument
4800 list. If it was, this will not work if PARM_BOUNDARY is not
4801 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4802 if it becomes a problem. Exception is when BLKmode arrives
4803 with arguments not conforming to word_mode. */
4805 if (stack_parm
== 0)
4807 stack_parm
= assign_stack_local (BLKmode
, size_stored
, 0);
4808 PUT_MODE (stack_parm
, GET_MODE (entry_parm
));
4809 set_mem_attributes (stack_parm
, parm
, 1);
4811 else if (GET_CODE (entry_parm
) == PARALLEL
4812 && GET_MODE(entry_parm
) == BLKmode
)
4814 else if (PARM_BOUNDARY
% BITS_PER_WORD
!= 0)
4817 mem
= validize_mem (stack_parm
);
4819 /* Handle calls that pass values in multiple non-contiguous
4820 locations. The Irix 6 ABI has examples of this. */
4821 if (GET_CODE (entry_parm
) == PARALLEL
)
4822 emit_group_store (mem
, entry_parm
, TREE_TYPE (parm
), size
);
4827 /* If SIZE is that of a mode no bigger than a word, just use
4828 that mode's store operation. */
4829 else if (size
<= UNITS_PER_WORD
)
4831 enum machine_mode mode
4832 = mode_for_size (size
* BITS_PER_UNIT
, MODE_INT
, 0);
4835 #ifdef BLOCK_REG_PADDING
4836 && (size
== UNITS_PER_WORD
4837 || (BLOCK_REG_PADDING (mode
, TREE_TYPE (parm
), 1)
4838 != (BYTES_BIG_ENDIAN
? upward
: downward
)))
4842 rtx reg
= gen_rtx_REG (mode
, REGNO (entry_parm
));
4843 emit_move_insn (change_address (mem
, mode
, 0), reg
);
4846 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
4847 machine must be aligned to the left before storing
4848 to memory. Note that the previous test doesn't
4849 handle all cases (e.g. SIZE == 3). */
4850 else if (size
!= UNITS_PER_WORD
4851 #ifdef BLOCK_REG_PADDING
4852 && (BLOCK_REG_PADDING (mode
, TREE_TYPE (parm
), 1)
4860 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
4861 rtx reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
4863 x
= expand_binop (word_mode
, ashl_optab
, reg
,
4864 GEN_INT (by
), 0, 1, OPTAB_WIDEN
);
4865 tem
= change_address (mem
, word_mode
, 0);
4866 emit_move_insn (tem
, x
);
4869 move_block_from_reg (REGNO (entry_parm
), mem
,
4870 size_stored
/ UNITS_PER_WORD
);
4873 move_block_from_reg (REGNO (entry_parm
), mem
,
4874 size_stored
/ UNITS_PER_WORD
);
4876 /* If parm is already bound to register pair, don't change
4878 if (! DECL_RTL_SET_P (parm
))
4879 SET_DECL_RTL (parm
, stack_parm
);
4881 else if (! ((! optimize
4882 && ! DECL_REGISTER (parm
))
4883 || TREE_SIDE_EFFECTS (parm
)
4884 /* If -ffloat-store specified, don't put explicit
4885 float variables into registers. */
4886 || (flag_float_store
4887 && TREE_CODE (TREE_TYPE (parm
)) == REAL_TYPE
))
4888 /* Always assign pseudo to structure return or item passed
4889 by invisible reference. */
4890 || passed_pointer
|| parm
== function_result_decl
)
4892 /* Store the parm in a pseudoregister during the function, but we
4893 may need to do it in a wider mode. */
4896 unsigned int regno
, regnoi
= 0, regnor
= 0;
4898 unsignedp
= TREE_UNSIGNED (TREE_TYPE (parm
));
4900 promoted_nominal_mode
4901 = promote_mode (TREE_TYPE (parm
), nominal_mode
, &unsignedp
, 0);
4903 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
4904 mark_user_reg (parmreg
);
4906 /* If this was an item that we received a pointer to, set DECL_RTL
4910 rtx x
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type
)),
4912 set_mem_attributes (x
, parm
, 1);
4913 SET_DECL_RTL (parm
, x
);
4917 SET_DECL_RTL (parm
, parmreg
);
4918 maybe_set_unchanging (DECL_RTL (parm
), parm
);
4921 /* Copy the value into the register. */
4922 if (nominal_mode
!= passed_mode
4923 || promoted_nominal_mode
!= promoted_mode
)
4926 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4927 mode, by the caller. We now have to convert it to
4928 NOMINAL_MODE, if different. However, PARMREG may be in
4929 a different mode than NOMINAL_MODE if it is being stored
4932 If ENTRY_PARM is a hard register, it might be in a register
4933 not valid for operating in its mode (e.g., an odd-numbered
4934 register for a DFmode). In that case, moves are the only
4935 thing valid, so we can't do a convert from there. This
4936 occurs when the calling sequence allow such misaligned
4939 In addition, the conversion may involve a call, which could
4940 clobber parameters which haven't been copied to pseudo
4941 registers yet. Therefore, we must first copy the parm to
4942 a pseudo reg here, and save the conversion until after all
4943 parameters have been moved. */
4945 rtx tempreg
= gen_reg_rtx (GET_MODE (entry_parm
));
4947 emit_move_insn (tempreg
, validize_mem (entry_parm
));
4949 push_to_sequence (conversion_insns
);
4950 tempreg
= convert_to_mode (nominal_mode
, tempreg
, unsignedp
);
4952 if (GET_CODE (tempreg
) == SUBREG
4953 && GET_MODE (tempreg
) == nominal_mode
4954 && GET_CODE (SUBREG_REG (tempreg
)) == REG
4955 && nominal_mode
== passed_mode
4956 && GET_MODE (SUBREG_REG (tempreg
)) == GET_MODE (entry_parm
)
4957 && GET_MODE_SIZE (GET_MODE (tempreg
))
4958 < GET_MODE_SIZE (GET_MODE (entry_parm
)))
4960 /* The argument is already sign/zero extended, so note it
4962 SUBREG_PROMOTED_VAR_P (tempreg
) = 1;
4963 SUBREG_PROMOTED_UNSIGNED_SET (tempreg
, unsignedp
);
4966 /* TREE_USED gets set erroneously during expand_assignment. */
4967 save_tree_used
= TREE_USED (parm
);
4968 expand_assignment (parm
,
4969 make_tree (nominal_type
, tempreg
), 0);
4970 TREE_USED (parm
) = save_tree_used
;
4971 conversion_insns
= get_insns ();
4976 emit_move_insn (parmreg
, validize_mem (entry_parm
));
4978 /* If we were passed a pointer but the actual value
4979 can safely live in a register, put it in one. */
4980 if (passed_pointer
&& TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
4981 /* If by-reference argument was promoted, demote it. */
4982 && (TYPE_MODE (TREE_TYPE (parm
)) != GET_MODE (DECL_RTL (parm
))
4984 && ! DECL_REGISTER (parm
))
4985 || TREE_SIDE_EFFECTS (parm
)
4986 /* If -ffloat-store specified, don't put explicit
4987 float variables into registers. */
4988 || (flag_float_store
4989 && TREE_CODE (TREE_TYPE (parm
)) == REAL_TYPE
))))
4991 /* We can't use nominal_mode, because it will have been set to
4992 Pmode above. We must use the actual mode of the parm. */
4993 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
4994 mark_user_reg (parmreg
);
4995 if (GET_MODE (parmreg
) != GET_MODE (DECL_RTL (parm
)))
4997 rtx tempreg
= gen_reg_rtx (GET_MODE (DECL_RTL (parm
)));
4998 int unsigned_p
= TREE_UNSIGNED (TREE_TYPE (parm
));
4999 push_to_sequence (conversion_insns
);
5000 emit_move_insn (tempreg
, DECL_RTL (parm
));
5002 convert_to_mode (GET_MODE (parmreg
),
5005 emit_move_insn (parmreg
, DECL_RTL (parm
));
5006 conversion_insns
= get_insns();
5011 emit_move_insn (parmreg
, DECL_RTL (parm
));
5012 SET_DECL_RTL (parm
, parmreg
);
5013 /* STACK_PARM is the pointer, not the parm, and PARMREG is
5017 #ifdef FUNCTION_ARG_CALLEE_COPIES
5018 /* If we are passed an arg by reference and it is our responsibility
5019 to make a copy, do it now.
5020 PASSED_TYPE and PASSED mode now refer to the pointer, not the
5021 original argument, so we must recreate them in the call to
5022 FUNCTION_ARG_CALLEE_COPIES. */
5023 /* ??? Later add code to handle the case that if the argument isn't
5024 modified, don't do the copy. */
5026 else if (passed_pointer
5027 && FUNCTION_ARG_CALLEE_COPIES (args_so_far
,
5028 TYPE_MODE (TREE_TYPE (passed_type
)),
5029 TREE_TYPE (passed_type
),
5031 && ! TREE_ADDRESSABLE (TREE_TYPE (passed_type
)))
5034 tree type
= TREE_TYPE (passed_type
);
5036 /* This sequence may involve a library call perhaps clobbering
5037 registers that haven't been copied to pseudos yet. */
5039 push_to_sequence (conversion_insns
);
5041 if (!COMPLETE_TYPE_P (type
)
5042 || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
5043 /* This is a variable sized object. */
5044 copy
= gen_rtx_MEM (BLKmode
,
5045 allocate_dynamic_stack_space
5046 (expr_size (parm
), NULL_RTX
,
5047 TYPE_ALIGN (type
)));
5049 copy
= assign_stack_temp (TYPE_MODE (type
),
5050 int_size_in_bytes (type
), 1);
5051 set_mem_attributes (copy
, parm
, 1);
5053 store_expr (parm
, copy
, 0);
5054 emit_move_insn (parmreg
, XEXP (copy
, 0));
5055 conversion_insns
= get_insns ();
5059 #endif /* FUNCTION_ARG_CALLEE_COPIES */
5061 /* In any case, record the parm's desired stack location
5062 in case we later discover it must live in the stack.
5064 If it is a COMPLEX value, store the stack location for both
5067 if (GET_CODE (parmreg
) == CONCAT
)
5068 regno
= MAX (REGNO (XEXP (parmreg
, 0)), REGNO (XEXP (parmreg
, 1)));
5070 regno
= REGNO (parmreg
);
5072 if (regno
>= max_parm_reg
)
5075 int old_max_parm_reg
= max_parm_reg
;
5077 /* It's slow to expand this one register at a time,
5078 but it's also rare and we need max_parm_reg to be
5079 precisely correct. */
5080 max_parm_reg
= regno
+ 1;
5081 new = ggc_realloc (parm_reg_stack_loc
,
5082 max_parm_reg
* sizeof (rtx
));
5083 memset (new + old_max_parm_reg
, 0,
5084 (max_parm_reg
- old_max_parm_reg
) * sizeof (rtx
));
5085 parm_reg_stack_loc
= new;
5088 if (GET_CODE (parmreg
) == CONCAT
)
5090 enum machine_mode submode
= GET_MODE (XEXP (parmreg
, 0));
5092 regnor
= REGNO (gen_realpart (submode
, parmreg
));
5093 regnoi
= REGNO (gen_imagpart (submode
, parmreg
));
5095 if (stack_parm
!= 0)
5097 parm_reg_stack_loc
[regnor
]
5098 = gen_realpart (submode
, stack_parm
);
5099 parm_reg_stack_loc
[regnoi
]
5100 = gen_imagpart (submode
, stack_parm
);
5104 parm_reg_stack_loc
[regnor
] = 0;
5105 parm_reg_stack_loc
[regnoi
] = 0;
5109 parm_reg_stack_loc
[REGNO (parmreg
)] = stack_parm
;
5111 /* Mark the register as eliminable if we did no conversion
5112 and it was copied from memory at a fixed offset,
5113 and the arg pointer was not copied to a pseudo-reg.
5114 If the arg pointer is a pseudo reg or the offset formed
5115 an invalid address, such memory-equivalences
5116 as we make here would screw up life analysis for it. */
5117 if (nominal_mode
== passed_mode
5120 && GET_CODE (stack_parm
) == MEM
5121 && locate
.offset
.var
== 0
5122 && reg_mentioned_p (virtual_incoming_args_rtx
,
5123 XEXP (stack_parm
, 0)))
5125 rtx linsn
= get_last_insn ();
5128 /* Mark complex types separately. */
5129 if (GET_CODE (parmreg
) == CONCAT
)
5130 /* Scan backwards for the set of the real and
5132 for (sinsn
= linsn
; sinsn
!= 0;
5133 sinsn
= prev_nonnote_insn (sinsn
))
5135 set
= single_set (sinsn
);
5137 && SET_DEST (set
) == regno_reg_rtx
[regnoi
])
5139 = gen_rtx_EXPR_LIST (REG_EQUIV
,
5140 parm_reg_stack_loc
[regnoi
],
5143 && SET_DEST (set
) == regno_reg_rtx
[regnor
])
5145 = gen_rtx_EXPR_LIST (REG_EQUIV
,
5146 parm_reg_stack_loc
[regnor
],
5149 else if ((set
= single_set (linsn
)) != 0
5150 && SET_DEST (set
) == parmreg
)
5152 = gen_rtx_EXPR_LIST (REG_EQUIV
,
5153 stack_parm
, REG_NOTES (linsn
));
5156 /* For pointer data type, suggest pointer register. */
5157 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
5158 mark_reg_pointer (parmreg
,
5159 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
5161 /* If something wants our address, try to use ADDRESSOF. */
5162 if (TREE_ADDRESSABLE (parm
))
5164 /* If we end up putting something into the stack,
5165 fixup_var_refs_insns will need to make a pass over
5166 all the instructions. It looks through the pending
5167 sequences -- but it can't see the ones in the
5168 CONVERSION_INSNS, if they're not on the sequence
5169 stack. So, we go back to that sequence, just so that
5170 the fixups will happen. */
5171 push_to_sequence (conversion_insns
);
5172 put_var_into_stack (parm
, /*rescan=*/true);
5173 conversion_insns
= get_insns ();
5179 /* Value must be stored in the stack slot STACK_PARM
5180 during function execution. */
5182 if (promoted_mode
!= nominal_mode
)
5184 /* Conversion is required. */
5185 rtx tempreg
= gen_reg_rtx (GET_MODE (entry_parm
));
5187 emit_move_insn (tempreg
, validize_mem (entry_parm
));
5189 push_to_sequence (conversion_insns
);
5190 entry_parm
= convert_to_mode (nominal_mode
, tempreg
,
5191 TREE_UNSIGNED (TREE_TYPE (parm
)));
5193 /* ??? This may need a big-endian conversion on sparc64. */
5194 stack_parm
= adjust_address (stack_parm
, nominal_mode
, 0);
5196 conversion_insns
= get_insns ();
5201 if (entry_parm
!= stack_parm
)
5203 if (stack_parm
== 0)
5206 = assign_stack_local (GET_MODE (entry_parm
),
5207 GET_MODE_SIZE (GET_MODE (entry_parm
)),
5209 set_mem_attributes (stack_parm
, parm
, 1);
5212 if (promoted_mode
!= nominal_mode
)
5214 push_to_sequence (conversion_insns
);
5215 emit_move_insn (validize_mem (stack_parm
),
5216 validize_mem (entry_parm
));
5217 conversion_insns
= get_insns ();
5221 emit_move_insn (validize_mem (stack_parm
),
5222 validize_mem (entry_parm
));
5225 SET_DECL_RTL (parm
, stack_parm
);
5229 if (targetm
.calls
.split_complex_arg
&& fnargs
!= orig_fnargs
)
5231 for (parm
= orig_fnargs
; parm
; parm
= TREE_CHAIN (parm
))
5233 if (TREE_CODE (TREE_TYPE (parm
)) == COMPLEX_TYPE
5234 && targetm
.calls
.split_complex_arg (TREE_TYPE (parm
)))
5236 rtx tmp
, real
, imag
;
5237 enum machine_mode inner
= GET_MODE_INNER (DECL_MODE (parm
));
5239 real
= DECL_RTL (fnargs
);
5240 imag
= DECL_RTL (TREE_CHAIN (fnargs
));
5241 if (inner
!= GET_MODE (real
))
5243 real
= gen_lowpart_SUBREG (inner
, real
);
5244 imag
= gen_lowpart_SUBREG (inner
, imag
);
5246 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
5247 SET_DECL_RTL (parm
, tmp
);
5249 real
= DECL_INCOMING_RTL (fnargs
);
5250 imag
= DECL_INCOMING_RTL (TREE_CHAIN (fnargs
));
5251 if (inner
!= GET_MODE (real
))
5253 real
= gen_lowpart_SUBREG (inner
, real
);
5254 imag
= gen_lowpart_SUBREG (inner
, imag
);
5256 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
5257 set_decl_incoming_rtl (parm
, tmp
);
5258 fnargs
= TREE_CHAIN (fnargs
);
5262 SET_DECL_RTL (parm
, DECL_RTL (fnargs
));
5263 set_decl_incoming_rtl (parm
, DECL_INCOMING_RTL (fnargs
));
5265 fnargs
= TREE_CHAIN (fnargs
);
5269 /* Output all parameter conversion instructions (possibly including calls)
5270 now that all parameters have been copied out of hard registers. */
5271 emit_insn (conversion_insns
);
5273 /* If we are receiving a struct value address as the first argument, set up
5274 the RTL for the function result. As this might require code to convert
5275 the transmitted address to Pmode, we do this here to ensure that possible
5276 preliminary conversions of the address have been emitted already. */
5277 if (function_result_decl
)
5279 tree result
= DECL_RESULT (fndecl
);
5280 rtx addr
= DECL_RTL (function_result_decl
);
5283 addr
= convert_memory_address (Pmode
, addr
);
5284 x
= gen_rtx_MEM (DECL_MODE (result
), addr
);
5285 set_mem_attributes (x
, result
, 1);
5286 SET_DECL_RTL (result
, x
);
5289 last_parm_insn
= get_last_insn ();
5291 /* We have aligned all the args, so add space for the pretend args. */
5292 stack_args_size
.constant
+= extra_pretend_bytes
;
5293 current_function_args_size
= stack_args_size
.constant
;
5295 /* Adjust function incoming argument size for alignment and
5298 #ifdef REG_PARM_STACK_SPACE
5299 current_function_args_size
= MAX (current_function_args_size
,
5300 REG_PARM_STACK_SPACE (fndecl
));
5303 current_function_args_size
5304 = ((current_function_args_size
+ STACK_BYTES
- 1)
5305 / STACK_BYTES
) * STACK_BYTES
;
5307 #ifdef ARGS_GROW_DOWNWARD
5308 current_function_arg_offset_rtx
5309 = (stack_args_size
.var
== 0 ? GEN_INT (-stack_args_size
.constant
)
5310 : expand_expr (size_diffop (stack_args_size
.var
,
5311 size_int (-stack_args_size
.constant
)),
5312 NULL_RTX
, VOIDmode
, 0));
5314 current_function_arg_offset_rtx
= ARGS_SIZE_RTX (stack_args_size
);
5317 /* See how many bytes, if any, of its args a function should try to pop
5320 current_function_pops_args
= RETURN_POPS_ARGS (fndecl
, TREE_TYPE (fndecl
),
5321 current_function_args_size
);
5323 /* For stdarg.h function, save info about
5324 regs and stack space used by the named args. */
5326 current_function_args_info
= args_so_far
;
5328 /* Set the rtx used for the function return value. Put this in its
5329 own variable so any optimizers that need this information don't have
5330 to include tree.h. Do this here so it gets done when an inlined
5331 function gets output. */
5333 current_function_return_rtx
5334 = (DECL_RTL_SET_P (DECL_RESULT (fndecl
))
5335 ? DECL_RTL (DECL_RESULT (fndecl
)) : NULL_RTX
);
5337 /* If scalar return value was computed in a pseudo-reg, or was a named
5338 return value that got dumped to the stack, copy that to the hard
5340 if (DECL_RTL_SET_P (DECL_RESULT (fndecl
)))
5342 tree decl_result
= DECL_RESULT (fndecl
);
5343 rtx decl_rtl
= DECL_RTL (decl_result
);
5345 if (REG_P (decl_rtl
)
5346 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
5347 : DECL_REGISTER (decl_result
))
5351 #ifdef FUNCTION_OUTGOING_VALUE
5352 real_decl_rtl
= FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result
),
5355 real_decl_rtl
= FUNCTION_VALUE (TREE_TYPE (decl_result
),
5358 REG_FUNCTION_VALUE_P (real_decl_rtl
) = 1;
5359 /* The delay slot scheduler assumes that current_function_return_rtx
5360 holds the hard register containing the return value, not a
5361 temporary pseudo. */
5362 current_function_return_rtx
= real_decl_rtl
;
5367 /* If ARGS contains entries with complex types, split the entry into two
5368 entries of the component type. Return a new list of substitutions are
5369 needed, else the old list. */
5372 split_complex_args (tree args
)
5376 /* Before allocating memory, check for the common case of no complex. */
5377 for (p
= args
; p
; p
= TREE_CHAIN (p
))
5379 tree type
= TREE_TYPE (p
);
5380 if (TREE_CODE (type
) == COMPLEX_TYPE
5381 && targetm
.calls
.split_complex_arg (type
))
5387 args
= copy_list (args
);
5389 for (p
= args
; p
; p
= TREE_CHAIN (p
))
5391 tree type
= TREE_TYPE (p
);
5392 if (TREE_CODE (type
) == COMPLEX_TYPE
5393 && targetm
.calls
.split_complex_arg (type
))
5396 tree subtype
= TREE_TYPE (type
);
5398 /* Rewrite the PARM_DECL's type with its component. */
5399 TREE_TYPE (p
) = subtype
;
5400 DECL_ARG_TYPE (p
) = TREE_TYPE (DECL_ARG_TYPE (p
));
5401 DECL_MODE (p
) = VOIDmode
;
5402 DECL_SIZE (p
) = NULL
;
5403 DECL_SIZE_UNIT (p
) = NULL
;
5406 /* Build a second synthetic decl. */
5407 decl
= build_decl (PARM_DECL
, NULL_TREE
, subtype
);
5408 DECL_ARG_TYPE (decl
) = DECL_ARG_TYPE (p
);
5409 layout_decl (decl
, 0);
5411 /* Splice it in; skip the new decl. */
5412 TREE_CHAIN (decl
) = TREE_CHAIN (p
);
5413 TREE_CHAIN (p
) = decl
;
5421 /* Indicate whether REGNO is an incoming argument to the current function
5422 that was promoted to a wider mode. If so, return the RTX for the
5423 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5424 that REGNO is promoted from and whether the promotion was signed or
5428 promoted_input_arg (unsigned int regno
, enum machine_mode
*pmode
, int *punsignedp
)
5432 for (arg
= DECL_ARGUMENTS (current_function_decl
); arg
;
5433 arg
= TREE_CHAIN (arg
))
5434 if (GET_CODE (DECL_INCOMING_RTL (arg
)) == REG
5435 && REGNO (DECL_INCOMING_RTL (arg
)) == regno
5436 && TYPE_MODE (DECL_ARG_TYPE (arg
)) == TYPE_MODE (TREE_TYPE (arg
)))
5438 enum machine_mode mode
= TYPE_MODE (TREE_TYPE (arg
));
5439 int unsignedp
= TREE_UNSIGNED (TREE_TYPE (arg
));
5441 mode
= promote_mode (TREE_TYPE (arg
), mode
, &unsignedp
, 1);
5442 if (mode
== GET_MODE (DECL_INCOMING_RTL (arg
))
5443 && mode
!= DECL_MODE (arg
))
5445 *pmode
= DECL_MODE (arg
);
5446 *punsignedp
= unsignedp
;
5447 return DECL_INCOMING_RTL (arg
);
5455 /* Compute the size and offset from the start of the stacked arguments for a
5456 parm passed in mode PASSED_MODE and with type TYPE.
5458 INITIAL_OFFSET_PTR points to the current offset into the stacked
5461 The starting offset and size for this parm are returned in
5462 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
5463 nonzero, the offset is that of stack slot, which is returned in
5464 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
5465 padding required from the initial offset ptr to the stack slot.
5467 IN_REGS is nonzero if the argument will be passed in registers. It will
5468 never be set if REG_PARM_STACK_SPACE is not defined.
5470 FNDECL is the function in which the argument was defined.
5472 There are two types of rounding that are done. The first, controlled by
5473 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5474 list to be aligned to the specific boundary (in bits). This rounding
5475 affects the initial and starting offsets, but not the argument size.
5477 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5478 optionally rounds the size of the parm to PARM_BOUNDARY. The
5479 initial offset is not affected by this rounding, while the size always
5480 is and the starting offset may be. */
5482 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
5483 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
5484 callers pass in the total size of args so far as
5485 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
5488 locate_and_pad_parm (enum machine_mode passed_mode
, tree type
, int in_regs
,
5489 int partial
, tree fndecl ATTRIBUTE_UNUSED
,
5490 struct args_size
*initial_offset_ptr
,
5491 struct locate_and_pad_arg_data
*locate
)
5494 enum direction where_pad
;
5496 int reg_parm_stack_space
= 0;
5497 int part_size_in_regs
;
5499 #ifdef REG_PARM_STACK_SPACE
5500 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
5502 /* If we have found a stack parm before we reach the end of the
5503 area reserved for registers, skip that area. */
5506 if (reg_parm_stack_space
> 0)
5508 if (initial_offset_ptr
->var
)
5510 initial_offset_ptr
->var
5511 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
5512 ssize_int (reg_parm_stack_space
));
5513 initial_offset_ptr
->constant
= 0;
5515 else if (initial_offset_ptr
->constant
< reg_parm_stack_space
)
5516 initial_offset_ptr
->constant
= reg_parm_stack_space
;
5519 #endif /* REG_PARM_STACK_SPACE */
5521 part_size_in_regs
= 0;
5522 if (reg_parm_stack_space
== 0)
5523 part_size_in_regs
= ((partial
* UNITS_PER_WORD
)
5524 / (PARM_BOUNDARY
/ BITS_PER_UNIT
)
5525 * (PARM_BOUNDARY
/ BITS_PER_UNIT
));
5528 = type
? size_in_bytes (type
) : size_int (GET_MODE_SIZE (passed_mode
));
5529 where_pad
= FUNCTION_ARG_PADDING (passed_mode
, type
);
5530 boundary
= FUNCTION_ARG_BOUNDARY (passed_mode
, type
);
5531 locate
->where_pad
= where_pad
;
5533 #ifdef ARGS_GROW_DOWNWARD
5534 locate
->slot_offset
.constant
= -initial_offset_ptr
->constant
;
5535 if (initial_offset_ptr
->var
)
5536 locate
->slot_offset
.var
= size_binop (MINUS_EXPR
, ssize_int (0),
5537 initial_offset_ptr
->var
);
5541 if (where_pad
!= none
5542 && (!host_integerp (sizetree
, 1)
5543 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
5544 s2
= round_up (s2
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
5545 SUB_PARM_SIZE (locate
->slot_offset
, s2
);
5548 locate
->slot_offset
.constant
+= part_size_in_regs
;
5551 #ifdef REG_PARM_STACK_SPACE
5552 || REG_PARM_STACK_SPACE (fndecl
) > 0
5555 pad_to_arg_alignment (&locate
->slot_offset
, boundary
,
5556 &locate
->alignment_pad
);
5558 locate
->size
.constant
= (-initial_offset_ptr
->constant
5559 - locate
->slot_offset
.constant
);
5560 if (initial_offset_ptr
->var
)
5561 locate
->size
.var
= size_binop (MINUS_EXPR
,
5562 size_binop (MINUS_EXPR
,
5564 initial_offset_ptr
->var
),
5565 locate
->slot_offset
.var
);
5567 /* Pad_below needs the pre-rounded size to know how much to pad
5569 locate
->offset
= locate
->slot_offset
;
5570 if (where_pad
== downward
)
5571 pad_below (&locate
->offset
, passed_mode
, sizetree
);
5573 #else /* !ARGS_GROW_DOWNWARD */
5575 #ifdef REG_PARM_STACK_SPACE
5576 || REG_PARM_STACK_SPACE (fndecl
) > 0
5579 pad_to_arg_alignment (initial_offset_ptr
, boundary
,
5580 &locate
->alignment_pad
);
5581 locate
->slot_offset
= *initial_offset_ptr
;
5583 #ifdef PUSH_ROUNDING
5584 if (passed_mode
!= BLKmode
)
5585 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
5588 /* Pad_below needs the pre-rounded size to know how much to pad below
5589 so this must be done before rounding up. */
5590 locate
->offset
= locate
->slot_offset
;
5591 if (where_pad
== downward
)
5592 pad_below (&locate
->offset
, passed_mode
, sizetree
);
5594 if (where_pad
!= none
5595 && (!host_integerp (sizetree
, 1)
5596 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
5597 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
5599 ADD_PARM_SIZE (locate
->size
, sizetree
);
5601 locate
->size
.constant
-= part_size_in_regs
;
5602 #endif /* ARGS_GROW_DOWNWARD */
5605 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5606 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5609 pad_to_arg_alignment (struct args_size
*offset_ptr
, int boundary
,
5610 struct args_size
*alignment_pad
)
5612 tree save_var
= NULL_TREE
;
5613 HOST_WIDE_INT save_constant
= 0;
5614 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
5615 HOST_WIDE_INT sp_offset
= STACK_POINTER_OFFSET
;
5617 #ifdef SPARC_STACK_BOUNDARY_HACK
5618 /* The sparc port has a bug. It sometimes claims a STACK_BOUNDARY
5619 higher than the real alignment of %sp. However, when it does this,
5620 the alignment of %sp+STACK_POINTER_OFFSET will be STACK_BOUNDARY.
5621 This is a temporary hack while the sparc port is fixed. */
5622 if (SPARC_STACK_BOUNDARY_HACK
)
5626 if (boundary
> PARM_BOUNDARY
&& boundary
> STACK_BOUNDARY
)
5628 save_var
= offset_ptr
->var
;
5629 save_constant
= offset_ptr
->constant
;
5632 alignment_pad
->var
= NULL_TREE
;
5633 alignment_pad
->constant
= 0;
5635 if (boundary
> BITS_PER_UNIT
)
5637 if (offset_ptr
->var
)
5639 tree sp_offset_tree
= ssize_int (sp_offset
);
5640 tree offset
= size_binop (PLUS_EXPR
,
5641 ARGS_SIZE_TREE (*offset_ptr
),
5643 #ifdef ARGS_GROW_DOWNWARD
5644 tree rounded
= round_down (offset
, boundary
/ BITS_PER_UNIT
);
5646 tree rounded
= round_up (offset
, boundary
/ BITS_PER_UNIT
);
5649 offset_ptr
->var
= size_binop (MINUS_EXPR
, rounded
, sp_offset_tree
);
5650 /* ARGS_SIZE_TREE includes constant term. */
5651 offset_ptr
->constant
= 0;
5652 if (boundary
> PARM_BOUNDARY
&& boundary
> STACK_BOUNDARY
)
5653 alignment_pad
->var
= size_binop (MINUS_EXPR
, offset_ptr
->var
,
5658 offset_ptr
->constant
= -sp_offset
+
5659 #ifdef ARGS_GROW_DOWNWARD
5660 FLOOR_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
5662 CEIL_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
5664 if (boundary
> PARM_BOUNDARY
&& boundary
> STACK_BOUNDARY
)
5665 alignment_pad
->constant
= offset_ptr
->constant
- save_constant
;
5671 pad_below (struct args_size
*offset_ptr
, enum machine_mode passed_mode
, tree sizetree
)
5673 if (passed_mode
!= BLKmode
)
5675 if (GET_MODE_BITSIZE (passed_mode
) % PARM_BOUNDARY
)
5676 offset_ptr
->constant
5677 += (((GET_MODE_BITSIZE (passed_mode
) + PARM_BOUNDARY
- 1)
5678 / PARM_BOUNDARY
* PARM_BOUNDARY
/ BITS_PER_UNIT
)
5679 - GET_MODE_SIZE (passed_mode
));
5683 if (TREE_CODE (sizetree
) != INTEGER_CST
5684 || (TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)
5686 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5687 tree s2
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
5689 ADD_PARM_SIZE (*offset_ptr
, s2
);
5690 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
5695 /* Walk the tree of blocks describing the binding levels within a function
5696 and warn about uninitialized variables.
5697 This is done after calling flow_analysis and before global_alloc
5698 clobbers the pseudo-regs to hard regs. */
5701 uninitialized_vars_warning (tree block
)
5704 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
5706 if (warn_uninitialized
5707 && TREE_CODE (decl
) == VAR_DECL
5708 /* These warnings are unreliable for and aggregates
5709 because assigning the fields one by one can fail to convince
5710 flow.c that the entire aggregate was initialized.
5711 Unions are troublesome because members may be shorter. */
5712 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl
))
5713 && DECL_RTL_SET_P (decl
)
5714 && GET_CODE (DECL_RTL (decl
)) == REG
5715 /* Global optimizations can make it difficult to determine if a
5716 particular variable has been initialized. However, a VAR_DECL
5717 with a nonzero DECL_INITIAL had an initializer, so do not
5718 claim it is potentially uninitialized.
5720 When the DECL_INITIAL is NULL call the language hook to tell us
5721 if we want to warn. */
5722 && (DECL_INITIAL (decl
) == NULL_TREE
|| lang_hooks
.decl_uninit (decl
))
5723 && regno_uninitialized (REGNO (DECL_RTL (decl
))))
5724 warning ("%J'%D' might be used uninitialized in this function",
5727 && TREE_CODE (decl
) == VAR_DECL
5728 && DECL_RTL_SET_P (decl
)
5729 && GET_CODE (DECL_RTL (decl
)) == REG
5730 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl
))))
5731 warning ("%Jvariable '%D' might be clobbered by `longjmp' or `vfork'",
5734 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= TREE_CHAIN (sub
))
5735 uninitialized_vars_warning (sub
);
5738 /* Do the appropriate part of uninitialized_vars_warning
5739 but for arguments instead of local variables. */
5742 setjmp_args_warning (void)
5745 for (decl
= DECL_ARGUMENTS (current_function_decl
);
5746 decl
; decl
= TREE_CHAIN (decl
))
5747 if (DECL_RTL (decl
) != 0
5748 && GET_CODE (DECL_RTL (decl
)) == REG
5749 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl
))))
5750 warning ("%Jargument '%D' might be clobbered by `longjmp' or `vfork'",
5754 /* If this function call setjmp, put all vars into the stack
5755 unless they were declared `register'. */
5758 setjmp_protect (tree block
)
5761 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
5762 if ((TREE_CODE (decl
) == VAR_DECL
5763 || TREE_CODE (decl
) == PARM_DECL
)
5764 && DECL_RTL (decl
) != 0
5765 && (GET_CODE (DECL_RTL (decl
)) == REG
5766 || (GET_CODE (DECL_RTL (decl
)) == MEM
5767 && GET_CODE (XEXP (DECL_RTL (decl
), 0)) == ADDRESSOF
))
5768 /* If this variable came from an inline function, it must be
5769 that its life doesn't overlap the setjmp. If there was a
5770 setjmp in the function, it would already be in memory. We
5771 must exclude such variable because their DECL_RTL might be
5772 set to strange things such as virtual_stack_vars_rtx. */
5773 && ! DECL_FROM_INLINE (decl
)
5775 #ifdef NON_SAVING_SETJMP
5776 /* If longjmp doesn't restore the registers,
5777 don't put anything in them. */
5781 ! DECL_REGISTER (decl
)))
5782 put_var_into_stack (decl
, /*rescan=*/true);
5783 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= TREE_CHAIN (sub
))
5784 setjmp_protect (sub
);
5787 /* Like the previous function, but for args instead of local variables. */
5790 setjmp_protect_args (void)
5793 for (decl
= DECL_ARGUMENTS (current_function_decl
);
5794 decl
; decl
= TREE_CHAIN (decl
))
5795 if ((TREE_CODE (decl
) == VAR_DECL
5796 || TREE_CODE (decl
) == PARM_DECL
)
5797 && DECL_RTL (decl
) != 0
5798 && (GET_CODE (DECL_RTL (decl
)) == REG
5799 || (GET_CODE (DECL_RTL (decl
)) == MEM
5800 && GET_CODE (XEXP (DECL_RTL (decl
), 0)) == ADDRESSOF
))
5802 /* If longjmp doesn't restore the registers,
5803 don't put anything in them. */
5804 #ifdef NON_SAVING_SETJMP
5808 ! DECL_REGISTER (decl
)))
5809 put_var_into_stack (decl
, /*rescan=*/true);
5812 /* Return the context-pointer register corresponding to DECL,
5813 or 0 if it does not need one. */
5816 lookup_static_chain (tree decl
)
5818 tree context
= decl_function_context (decl
);
5822 || (TREE_CODE (decl
) == FUNCTION_DECL
&& DECL_NO_STATIC_CHAIN (decl
)))
5825 /* We treat inline_function_decl as an alias for the current function
5826 because that is the inline function whose vars, types, etc.
5827 are being merged into the current function.
5828 See expand_inline_function. */
5829 if (context
== current_function_decl
|| context
== inline_function_decl
)
5830 return virtual_stack_vars_rtx
;
5832 for (link
= context_display
; link
; link
= TREE_CHAIN (link
))
5833 if (TREE_PURPOSE (link
) == context
)
5834 return RTL_EXPR_RTL (TREE_VALUE (link
));
5839 /* Convert a stack slot address ADDR for variable VAR
5840 (from a containing function)
5841 into an address valid in this function (using a static chain). */
5844 fix_lexical_addr (rtx addr
, tree var
)
5847 HOST_WIDE_INT displacement
;
5848 tree context
= decl_function_context (var
);
5849 struct function
*fp
;
5852 /* If this is the present function, we need not do anything. */
5853 if (context
== current_function_decl
|| context
== inline_function_decl
)
5856 fp
= find_function_data (context
);
5858 if (GET_CODE (addr
) == ADDRESSOF
&& GET_CODE (XEXP (addr
, 0)) == MEM
)
5859 addr
= XEXP (XEXP (addr
, 0), 0);
5861 /* Decode given address as base reg plus displacement. */
5862 if (GET_CODE (addr
) == REG
)
5863 basereg
= addr
, displacement
= 0;
5864 else if (GET_CODE (addr
) == PLUS
&& GET_CODE (XEXP (addr
, 1)) == CONST_INT
)
5865 basereg
= XEXP (addr
, 0), displacement
= INTVAL (XEXP (addr
, 1));
5869 /* We accept vars reached via the containing function's
5870 incoming arg pointer and via its stack variables pointer. */
5871 if (basereg
== fp
->internal_arg_pointer
)
5873 /* If reached via arg pointer, get the arg pointer value
5874 out of that function's stack frame.
5876 There are two cases: If a separate ap is needed, allocate a
5877 slot in the outer function for it and dereference it that way.
5878 This is correct even if the real ap is actually a pseudo.
5879 Otherwise, just adjust the offset from the frame pointer to
5882 #ifdef NEED_SEPARATE_AP
5885 addr
= get_arg_pointer_save_area (fp
);
5886 addr
= fix_lexical_addr (XEXP (addr
, 0), var
);
5887 addr
= memory_address (Pmode
, addr
);
5889 base
= gen_rtx_MEM (Pmode
, addr
);
5890 set_mem_alias_set (base
, get_frame_alias_set ());
5891 base
= copy_to_reg (base
);
5893 displacement
+= (FIRST_PARM_OFFSET (context
) - STARTING_FRAME_OFFSET
);
5894 base
= lookup_static_chain (var
);
5898 else if (basereg
== virtual_stack_vars_rtx
)
5900 /* This is the same code as lookup_static_chain, duplicated here to
5901 avoid an extra call to decl_function_context. */
5904 for (link
= context_display
; link
; link
= TREE_CHAIN (link
))
5905 if (TREE_PURPOSE (link
) == context
)
5907 base
= RTL_EXPR_RTL (TREE_VALUE (link
));
5915 /* Use same offset, relative to appropriate static chain or argument
5917 return plus_constant (base
, displacement
);
5920 /* Return the address of the trampoline for entering nested fn FUNCTION.
5921 If necessary, allocate a trampoline (in the stack frame)
5922 and emit rtl to initialize its contents (at entry to this function). */
5925 trampoline_address (tree function
)
5930 struct function
*fp
;
5933 /* Find an existing trampoline and return it. */
5934 for (link
= trampoline_list
; link
; link
= TREE_CHAIN (link
))
5935 if (TREE_PURPOSE (link
) == function
)
5937 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link
)), 0));
5939 for (fp
= outer_function_chain
; fp
; fp
= fp
->outer
)
5940 for (link
= fp
->x_trampoline_list
; link
; link
= TREE_CHAIN (link
))
5941 if (TREE_PURPOSE (link
) == function
)
5943 tramp
= fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link
)), 0),
5945 return adjust_trampoline_addr (tramp
);
5948 /* None exists; we must make one. */
5950 /* Find the `struct function' for the function containing FUNCTION. */
5952 fn_context
= decl_function_context (function
);
5953 if (fn_context
!= current_function_decl
5954 && fn_context
!= inline_function_decl
)
5955 fp
= find_function_data (fn_context
);
5957 /* Allocate run-time space for this trampoline. */
5958 /* If rounding needed, allocate extra space
5959 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5960 #define TRAMPOLINE_REAL_SIZE \
5961 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5962 tramp
= assign_stack_local_1 (BLKmode
, TRAMPOLINE_REAL_SIZE
, 0,
5964 /* Record the trampoline for reuse and note it for later initialization
5965 by expand_function_end. */
5968 rtlexp
= make_node (RTL_EXPR
);
5969 RTL_EXPR_RTL (rtlexp
) = tramp
;
5970 fp
->x_trampoline_list
= tree_cons (function
, rtlexp
,
5971 fp
->x_trampoline_list
);
5975 /* Make the RTL_EXPR node temporary, not momentary, so that the
5976 trampoline_list doesn't become garbage. */
5977 rtlexp
= make_node (RTL_EXPR
);
5979 RTL_EXPR_RTL (rtlexp
) = tramp
;
5980 trampoline_list
= tree_cons (function
, rtlexp
, trampoline_list
);
5983 tramp
= fix_lexical_addr (XEXP (tramp
, 0), function
);
5984 return adjust_trampoline_addr (tramp
);
5987 /* Given a trampoline address,
5988 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5991 round_trampoline_addr (rtx tramp
)
5993 /* Round address up to desired boundary. */
5994 rtx temp
= gen_reg_rtx (Pmode
);
5995 rtx addend
= GEN_INT (TRAMPOLINE_ALIGNMENT
/ BITS_PER_UNIT
- 1);
5996 rtx mask
= GEN_INT (-TRAMPOLINE_ALIGNMENT
/ BITS_PER_UNIT
);
5998 temp
= expand_simple_binop (Pmode
, PLUS
, tramp
, addend
,
5999 temp
, 0, OPTAB_LIB_WIDEN
);
6000 tramp
= expand_simple_binop (Pmode
, AND
, temp
, mask
,
6001 temp
, 0, OPTAB_LIB_WIDEN
);
6006 /* Given a trampoline address, round it then apply any
6007 platform-specific adjustments so that the result can be used for a
6011 adjust_trampoline_addr (rtx tramp
)
6013 tramp
= round_trampoline_addr (tramp
);
6014 #ifdef TRAMPOLINE_ADJUST_ADDRESS
6015 TRAMPOLINE_ADJUST_ADDRESS (tramp
);
6020 /* Put all this function's BLOCK nodes including those that are chained
6021 onto the first block into a vector, and return it.
6022 Also store in each NOTE for the beginning or end of a block
6023 the index of that block in the vector.
6024 The arguments are BLOCK, the chain of top-level blocks of the function,
6025 and INSNS, the insn chain of the function. */
6028 identify_blocks (void)
6031 tree
*block_vector
, *last_block_vector
;
6033 tree block
= DECL_INITIAL (current_function_decl
);
6038 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
6039 depth-first order. */
6040 block_vector
= get_block_vector (block
, &n_blocks
);
6041 block_stack
= xmalloc (n_blocks
* sizeof (tree
));
6043 last_block_vector
= identify_blocks_1 (get_insns (),
6045 block_vector
+ n_blocks
,
6048 /* If we didn't use all of the subblocks, we've misplaced block notes. */
6049 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
6050 if (0 && last_block_vector
!= block_vector
+ n_blocks
)
6053 free (block_vector
);
6057 /* Subroutine of identify_blocks. Do the block substitution on the
6058 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
6060 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
6061 BLOCK_VECTOR is incremented for each block seen. */
6064 identify_blocks_1 (rtx insns
, tree
*block_vector
, tree
*end_block_vector
,
6065 tree
*orig_block_stack
)
6068 tree
*block_stack
= orig_block_stack
;
6070 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
6072 if (GET_CODE (insn
) == NOTE
)
6074 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_BEG
)
6078 /* If there are more block notes than BLOCKs, something
6080 if (block_vector
== end_block_vector
)
6083 b
= *block_vector
++;
6084 NOTE_BLOCK (insn
) = b
;
6087 else if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_END
)
6089 /* If there are more NOTE_INSN_BLOCK_ENDs than
6090 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
6091 if (block_stack
== orig_block_stack
)
6094 NOTE_BLOCK (insn
) = *--block_stack
;
6097 else if (GET_CODE (insn
) == CALL_INSN
6098 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
6100 rtx cp
= PATTERN (insn
);
6102 block_vector
= identify_blocks_1 (XEXP (cp
, 0), block_vector
,
6103 end_block_vector
, block_stack
);
6105 block_vector
= identify_blocks_1 (XEXP (cp
, 1), block_vector
,
6106 end_block_vector
, block_stack
);
6108 block_vector
= identify_blocks_1 (XEXP (cp
, 2), block_vector
,
6109 end_block_vector
, block_stack
);
6113 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
6114 something is badly wrong. */
6115 if (block_stack
!= orig_block_stack
)
6118 return block_vector
;
6121 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
6122 and create duplicate blocks. */
6123 /* ??? Need an option to either create block fragments or to create
6124 abstract origin duplicates of a source block. It really depends
6125 on what optimization has been performed. */
6128 reorder_blocks (void)
6130 tree block
= DECL_INITIAL (current_function_decl
);
6131 varray_type block_stack
;
6133 if (block
== NULL_TREE
)
6136 VARRAY_TREE_INIT (block_stack
, 10, "block_stack");
6138 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
6139 reorder_blocks_0 (block
);
6141 /* Prune the old trees away, so that they don't get in the way. */
6142 BLOCK_SUBBLOCKS (block
) = NULL_TREE
;
6143 BLOCK_CHAIN (block
) = NULL_TREE
;
6145 /* Recreate the block tree from the note nesting. */
6146 reorder_blocks_1 (get_insns (), block
, &block_stack
);
6147 BLOCK_SUBBLOCKS (block
) = blocks_nreverse (BLOCK_SUBBLOCKS (block
));
6149 /* Remove deleted blocks from the block fragment chains. */
6150 reorder_fix_fragments (block
);
6153 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
6156 reorder_blocks_0 (tree block
)
6160 TREE_ASM_WRITTEN (block
) = 0;
6161 reorder_blocks_0 (BLOCK_SUBBLOCKS (block
));
6162 block
= BLOCK_CHAIN (block
);
6167 reorder_blocks_1 (rtx insns
, tree current_block
, varray_type
*p_block_stack
)
6171 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
6173 if (GET_CODE (insn
) == NOTE
)
6175 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_BEG
)
6177 tree block
= NOTE_BLOCK (insn
);
6179 /* If we have seen this block before, that means it now
6180 spans multiple address regions. Create a new fragment. */
6181 if (TREE_ASM_WRITTEN (block
))
6183 tree new_block
= copy_node (block
);
6186 origin
= (BLOCK_FRAGMENT_ORIGIN (block
)
6187 ? BLOCK_FRAGMENT_ORIGIN (block
)
6189 BLOCK_FRAGMENT_ORIGIN (new_block
) = origin
;
6190 BLOCK_FRAGMENT_CHAIN (new_block
)
6191 = BLOCK_FRAGMENT_CHAIN (origin
);
6192 BLOCK_FRAGMENT_CHAIN (origin
) = new_block
;
6194 NOTE_BLOCK (insn
) = new_block
;
6198 BLOCK_SUBBLOCKS (block
) = 0;
6199 TREE_ASM_WRITTEN (block
) = 1;
6200 /* When there's only one block for the entire function,
6201 current_block == block and we mustn't do this, it
6202 will cause infinite recursion. */
6203 if (block
!= current_block
)
6205 BLOCK_SUPERCONTEXT (block
) = current_block
;
6206 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
6207 BLOCK_SUBBLOCKS (current_block
) = block
;
6208 current_block
= block
;
6210 VARRAY_PUSH_TREE (*p_block_stack
, block
);
6212 else if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_END
)
6214 NOTE_BLOCK (insn
) = VARRAY_TOP_TREE (*p_block_stack
);
6215 VARRAY_POP (*p_block_stack
);
6216 BLOCK_SUBBLOCKS (current_block
)
6217 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block
));
6218 current_block
= BLOCK_SUPERCONTEXT (current_block
);
6221 else if (GET_CODE (insn
) == CALL_INSN
6222 && GET_CODE (PATTERN (insn
)) == CALL_PLACEHOLDER
)
6224 rtx cp
= PATTERN (insn
);
6225 reorder_blocks_1 (XEXP (cp
, 0), current_block
, p_block_stack
);
6227 reorder_blocks_1 (XEXP (cp
, 1), current_block
, p_block_stack
);
6229 reorder_blocks_1 (XEXP (cp
, 2), current_block
, p_block_stack
);
6234 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
6235 appears in the block tree, select one of the fragments to become
6236 the new origin block. */
6239 reorder_fix_fragments (tree block
)
6243 tree dup_origin
= BLOCK_FRAGMENT_ORIGIN (block
);
6244 tree new_origin
= NULL_TREE
;
6248 if (! TREE_ASM_WRITTEN (dup_origin
))
6250 new_origin
= BLOCK_FRAGMENT_CHAIN (dup_origin
);
6252 /* Find the first of the remaining fragments. There must
6253 be at least one -- the current block. */
6254 while (! TREE_ASM_WRITTEN (new_origin
))
6255 new_origin
= BLOCK_FRAGMENT_CHAIN (new_origin
);
6256 BLOCK_FRAGMENT_ORIGIN (new_origin
) = NULL_TREE
;
6259 else if (! dup_origin
)
6262 /* Re-root the rest of the fragments to the new origin. In the
6263 case that DUP_ORIGIN was null, that means BLOCK was the origin
6264 of a chain of fragments and we want to remove those fragments
6265 that didn't make it to the output. */
6268 tree
*pp
= &BLOCK_FRAGMENT_CHAIN (new_origin
);
6273 if (TREE_ASM_WRITTEN (chain
))
6275 BLOCK_FRAGMENT_ORIGIN (chain
) = new_origin
;
6277 pp
= &BLOCK_FRAGMENT_CHAIN (chain
);
6279 chain
= BLOCK_FRAGMENT_CHAIN (chain
);
6284 reorder_fix_fragments (BLOCK_SUBBLOCKS (block
));
6285 block
= BLOCK_CHAIN (block
);
6289 /* Reverse the order of elements in the chain T of blocks,
6290 and return the new head of the chain (old last element). */
6293 blocks_nreverse (tree t
)
6295 tree prev
= 0, decl
, next
;
6296 for (decl
= t
; decl
; decl
= next
)
6298 next
= BLOCK_CHAIN (decl
);
6299 BLOCK_CHAIN (decl
) = prev
;
6305 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
6306 non-NULL, list them all into VECTOR, in a depth-first preorder
6307 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6311 all_blocks (tree block
, tree
*vector
)
6317 TREE_ASM_WRITTEN (block
) = 0;
6319 /* Record this block. */
6321 vector
[n_blocks
] = block
;
6325 /* Record the subblocks, and their subblocks... */
6326 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
6327 vector
? vector
+ n_blocks
: 0);
6328 block
= BLOCK_CHAIN (block
);
6334 /* Return a vector containing all the blocks rooted at BLOCK. The
6335 number of elements in the vector is stored in N_BLOCKS_P. The
6336 vector is dynamically allocated; it is the caller's responsibility
6337 to call `free' on the pointer returned. */
6340 get_block_vector (tree block
, int *n_blocks_p
)
6344 *n_blocks_p
= all_blocks (block
, NULL
);
6345 block_vector
= xmalloc (*n_blocks_p
* sizeof (tree
));
6346 all_blocks (block
, block_vector
);
6348 return block_vector
;
6351 static GTY(()) int next_block_index
= 2;
6353 /* Set BLOCK_NUMBER for all the blocks in FN. */
6356 number_blocks (tree fn
)
6362 /* For SDB and XCOFF debugging output, we start numbering the blocks
6363 from 1 within each function, rather than keeping a running
6365 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6366 if (write_symbols
== SDB_DEBUG
|| write_symbols
== XCOFF_DEBUG
)
6367 next_block_index
= 1;
6370 block_vector
= get_block_vector (DECL_INITIAL (fn
), &n_blocks
);
6372 /* The top-level BLOCK isn't numbered at all. */
6373 for (i
= 1; i
< n_blocks
; ++i
)
6374 /* We number the blocks from two. */
6375 BLOCK_NUMBER (block_vector
[i
]) = next_block_index
++;
6377 free (block_vector
);
6382 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6385 debug_find_var_in_block_tree (tree var
, tree block
)
6389 for (t
= BLOCK_VARS (block
); t
; t
= TREE_CHAIN (t
))
6393 for (t
= BLOCK_SUBBLOCKS (block
); t
; t
= TREE_CHAIN (t
))
6395 tree ret
= debug_find_var_in_block_tree (var
, t
);
6403 /* Allocate a function structure for FNDECL and set its contents
6407 allocate_struct_function (tree fndecl
)
6411 cfun
= ggc_alloc_cleared (sizeof (struct function
));
6413 max_parm_reg
= LAST_VIRTUAL_REGISTER
+ 1;
6415 cfun
->stack_alignment_needed
= STACK_BOUNDARY
;
6416 cfun
->preferred_stack_boundary
= STACK_BOUNDARY
;
6418 current_function_funcdef_no
= funcdef_no
++;
6420 cfun
->function_frequency
= FUNCTION_FREQUENCY_NORMAL
;
6422 init_stmt_for_function ();
6423 init_eh_for_function ();
6425 lang_hooks
.function
.init (cfun
);
6426 if (init_machine_status
)
6427 cfun
->machine
= (*init_machine_status
) ();
6432 DECL_STRUCT_FUNCTION (fndecl
) = cfun
;
6433 cfun
->decl
= fndecl
;
6435 result
= DECL_RESULT (fndecl
);
6436 if (aggregate_value_p (result
, fndecl
))
6438 #ifdef PCC_STATIC_STRUCT_RETURN
6439 current_function_returns_pcc_struct
= 1;
6441 current_function_returns_struct
= 1;
6444 current_function_returns_pointer
= POINTER_TYPE_P (TREE_TYPE (result
));
6446 current_function_needs_context
6447 = (decl_function_context (current_function_decl
) != 0
6448 && ! DECL_NO_STATIC_CHAIN (current_function_decl
));
6451 /* Reset cfun, and other non-struct-function variables to defaults as
6452 appropriate for emitting rtl at the start of a function. */
6455 prepare_function_start (tree fndecl
)
6457 if (fndecl
&& DECL_STRUCT_FUNCTION (fndecl
))
6458 cfun
= DECL_STRUCT_FUNCTION (fndecl
);
6460 allocate_struct_function (fndecl
);
6462 init_varasm_status (cfun
);
6465 cse_not_expected
= ! optimize
;
6467 /* Caller save not needed yet. */
6468 caller_save_needed
= 0;
6470 /* We haven't done register allocation yet. */
6473 /* Indicate that we need to distinguish between the return value of the
6474 present function and the return value of a function being called. */
6475 rtx_equal_function_value_matters
= 1;
6477 /* Indicate that we have not instantiated virtual registers yet. */
6478 virtuals_instantiated
= 0;
6480 /* Indicate that we want CONCATs now. */
6481 generating_concat_p
= 1;
6483 /* Indicate we have no need of a frame pointer yet. */
6484 frame_pointer_needed
= 0;
6487 /* Initialize the rtl expansion mechanism so that we can do simple things
6488 like generate sequences. This is used to provide a context during global
6489 initialization of some passes. */
6491 init_dummy_function_start (void)
6493 prepare_function_start (NULL
);
6496 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6497 and initialize static variables for generating RTL for the statements
6501 init_function_start (tree subr
)
6503 prepare_function_start (subr
);
6505 /* Within function body, compute a type's size as soon it is laid out. */
6506 immediate_size_expand
++;
6508 /* Prevent ever trying to delete the first instruction of a
6509 function. Also tell final how to output a linenum before the
6510 function prologue. Note linenums could be missing, e.g. when
6511 compiling a Java .class file. */
6512 if (DECL_SOURCE_LINE (subr
))
6513 emit_line_note (DECL_SOURCE_LOCATION (subr
));
6515 /* Make sure first insn is a note even if we don't want linenums.
6516 This makes sure the first insn will never be deleted.
6517 Also, final expects a note to appear there. */
6518 emit_note (NOTE_INSN_DELETED
);
6520 /* Warn if this value is an aggregate type,
6521 regardless of which calling convention we are using for it. */
6522 if (warn_aggregate_return
6523 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
6524 warning ("function returns an aggregate");
6527 /* Make sure all values used by the optimization passes have sane
6530 init_function_for_compilation (void)
6534 /* No prologue/epilogue insns yet. */
6535 VARRAY_GROW (prologue
, 0);
6536 VARRAY_GROW (epilogue
, 0);
6537 VARRAY_GROW (sibcall_epilogue
, 0);
6540 /* Expand a call to __main at the beginning of a possible main function. */
6542 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6543 #undef HAS_INIT_SECTION
6544 #define HAS_INIT_SECTION
6548 expand_main_function (void)
6550 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6551 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
)
6553 int align
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
6557 /* Forcibly align the stack. */
6558 #ifdef STACK_GROWS_DOWNWARD
6559 tmp
= expand_simple_binop (Pmode
, AND
, stack_pointer_rtx
, GEN_INT(-align
),
6560 stack_pointer_rtx
, 1, OPTAB_WIDEN
);
6562 tmp
= expand_simple_binop (Pmode
, PLUS
, stack_pointer_rtx
,
6563 GEN_INT (align
- 1), NULL_RTX
, 1, OPTAB_WIDEN
);
6564 tmp
= expand_simple_binop (Pmode
, AND
, tmp
, GEN_INT (-align
),
6565 stack_pointer_rtx
, 1, OPTAB_WIDEN
);
6567 if (tmp
!= stack_pointer_rtx
)
6568 emit_move_insn (stack_pointer_rtx
, tmp
);
6570 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6571 tmp
= force_reg (Pmode
, const0_rtx
);
6572 allocate_dynamic_stack_space (tmp
, NULL_RTX
, BIGGEST_ALIGNMENT
);
6576 for (tmp
= get_last_insn (); tmp
; tmp
= PREV_INSN (tmp
))
6577 if (NOTE_P (tmp
) && NOTE_LINE_NUMBER (tmp
) == NOTE_INSN_FUNCTION_BEG
)
6580 emit_insn_before (seq
, tmp
);
6586 #ifndef HAS_INIT_SECTION
6587 emit_library_call (init_one_libfunc (NAME__MAIN
), LCT_NORMAL
, VOIDmode
, 0);
6591 /* The PENDING_SIZES represent the sizes of variable-sized types.
6592 Create RTL for the various sizes now (using temporary variables),
6593 so that we can refer to the sizes from the RTL we are generating
6594 for the current function. The PENDING_SIZES are a TREE_LIST. The
6595 TREE_VALUE of each node is a SAVE_EXPR. */
6598 expand_pending_sizes (tree pending_sizes
)
6602 /* Evaluate now the sizes of any types declared among the arguments. */
6603 for (tem
= pending_sizes
; tem
; tem
= TREE_CHAIN (tem
))
6605 expand_expr (TREE_VALUE (tem
), const0_rtx
, VOIDmode
, 0);
6606 /* Flush the queue in case this parameter declaration has
6612 /* Start the RTL for a new function, and set variables used for
6614 SUBR is the FUNCTION_DECL node.
6615 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6616 the function's parameters, which must be run at any return statement. */
6619 expand_function_start (tree subr
, int parms_have_cleanups
)
6622 rtx last_ptr
= NULL_RTX
;
6624 /* Make sure volatile mem refs aren't considered
6625 valid operands of arithmetic insns. */
6626 init_recog_no_volatile ();
6628 current_function_instrument_entry_exit
6629 = (flag_instrument_function_entry_exit
6630 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
6632 current_function_profile
6634 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
6636 current_function_limit_stack
6637 = (stack_limit_rtx
!= NULL_RTX
&& ! DECL_NO_LIMIT_STACK (subr
));
6639 /* If function gets a static chain arg, store it in the stack frame.
6640 Do this first, so it gets the first stack slot offset. */
6641 if (current_function_needs_context
)
6643 last_ptr
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
6645 /* Delay copying static chain if it is not a register to avoid
6646 conflicts with regs used for parameters. */
6647 if (! SMALL_REGISTER_CLASSES
6648 || GET_CODE (static_chain_incoming_rtx
) == REG
)
6649 emit_move_insn (last_ptr
, static_chain_incoming_rtx
);
6652 /* If the parameters of this function need cleaning up, get a label
6653 for the beginning of the code which executes those cleanups. This must
6654 be done before doing anything with return_label. */
6655 if (parms_have_cleanups
)
6656 cleanup_label
= gen_label_rtx ();
6660 /* Make the label for return statements to jump to. Do not special
6661 case machines with special return instructions -- they will be
6662 handled later during jump, ifcvt, or epilogue creation. */
6663 return_label
= gen_label_rtx ();
6665 /* Initialize rtx used to return the value. */
6666 /* Do this before assign_parms so that we copy the struct value address
6667 before any library calls that assign parms might generate. */
6669 /* Decide whether to return the value in memory or in a register. */
6670 if (aggregate_value_p (DECL_RESULT (subr
), subr
))
6672 /* Returning something that won't go in a register. */
6673 rtx value_address
= 0;
6675 #ifdef PCC_STATIC_STRUCT_RETURN
6676 if (current_function_returns_pcc_struct
)
6678 int size
= int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr
)));
6679 value_address
= assemble_static_space (size
);
6684 rtx sv
= targetm
.calls
.struct_value_rtx (TREE_TYPE (subr
), 1);
6685 /* Expect to be passed the address of a place to store the value.
6686 If it is passed as an argument, assign_parms will take care of
6690 value_address
= gen_reg_rtx (Pmode
);
6691 emit_move_insn (value_address
, sv
);
6696 rtx x
= gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr
)), value_address
);
6697 set_mem_attributes (x
, DECL_RESULT (subr
), 1);
6698 SET_DECL_RTL (DECL_RESULT (subr
), x
);
6701 else if (DECL_MODE (DECL_RESULT (subr
)) == VOIDmode
)
6702 /* If return mode is void, this decl rtl should not be used. */
6703 SET_DECL_RTL (DECL_RESULT (subr
), NULL_RTX
);
6706 /* Compute the return values into a pseudo reg, which we will copy
6707 into the true return register after the cleanups are done. */
6709 /* In order to figure out what mode to use for the pseudo, we
6710 figure out what the mode of the eventual return register will
6711 actually be, and use that. */
6713 = hard_function_value (TREE_TYPE (DECL_RESULT (subr
)),
6716 /* Structures that are returned in registers are not aggregate_value_p,
6717 so we may see a PARALLEL or a REG. */
6718 if (REG_P (hard_reg
))
6719 SET_DECL_RTL (DECL_RESULT (subr
), gen_reg_rtx (GET_MODE (hard_reg
)));
6720 else if (GET_CODE (hard_reg
) == PARALLEL
)
6721 SET_DECL_RTL (DECL_RESULT (subr
), gen_group_rtx (hard_reg
));
6725 /* Set DECL_REGISTER flag so that expand_function_end will copy the
6726 result to the real return register(s). */
6727 DECL_REGISTER (DECL_RESULT (subr
)) = 1;
6730 /* Initialize rtx for parameters and local variables.
6731 In some cases this requires emitting insns. */
6733 assign_parms (subr
);
6735 /* Copy the static chain now if it wasn't a register. The delay is to
6736 avoid conflicts with the parameter passing registers. */
6738 if (SMALL_REGISTER_CLASSES
&& current_function_needs_context
)
6739 if (GET_CODE (static_chain_incoming_rtx
) != REG
)
6740 emit_move_insn (last_ptr
, static_chain_incoming_rtx
);
6742 /* The following was moved from init_function_start.
6743 The move is supposed to make sdb output more accurate. */
6744 /* Indicate the beginning of the function body,
6745 as opposed to parm setup. */
6746 emit_note (NOTE_INSN_FUNCTION_BEG
);
6748 if (GET_CODE (get_last_insn ()) != NOTE
)
6749 emit_note (NOTE_INSN_DELETED
);
6750 parm_birth_insn
= get_last_insn ();
6752 context_display
= 0;
6753 if (current_function_needs_context
)
6755 /* Fetch static chain values for containing functions. */
6756 tem
= decl_function_context (current_function_decl
);
6757 /* Copy the static chain pointer into a pseudo. If we have
6758 small register classes, copy the value from memory if
6759 static_chain_incoming_rtx is a REG. */
6762 /* If the static chain originally came in a register, put it back
6763 there, then move it out in the next insn. The reason for
6764 this peculiar code is to satisfy function integration. */
6765 if (SMALL_REGISTER_CLASSES
6766 && GET_CODE (static_chain_incoming_rtx
) == REG
)
6767 emit_move_insn (static_chain_incoming_rtx
, last_ptr
);
6768 last_ptr
= copy_to_reg (static_chain_incoming_rtx
);
6773 tree rtlexp
= make_node (RTL_EXPR
);
6775 RTL_EXPR_RTL (rtlexp
) = last_ptr
;
6776 context_display
= tree_cons (tem
, rtlexp
, context_display
);
6777 tem
= decl_function_context (tem
);
6780 /* Chain through stack frames, assuming pointer to next lexical frame
6781 is found at the place we always store it. */
6782 #ifdef FRAME_GROWS_DOWNWARD
6783 last_ptr
= plus_constant (last_ptr
,
6784 -(HOST_WIDE_INT
) GET_MODE_SIZE (Pmode
));
6786 last_ptr
= gen_rtx_MEM (Pmode
, memory_address (Pmode
, last_ptr
));
6787 set_mem_alias_set (last_ptr
, get_frame_alias_set ());
6788 last_ptr
= copy_to_reg (last_ptr
);
6790 /* If we are not optimizing, ensure that we know that this
6791 piece of context is live over the entire function. */
6793 save_expr_regs
= gen_rtx_EXPR_LIST (VOIDmode
, last_ptr
,
6798 if (current_function_instrument_entry_exit
)
6800 rtx fun
= DECL_RTL (current_function_decl
);
6801 if (GET_CODE (fun
) == MEM
)
6802 fun
= XEXP (fun
, 0);
6805 emit_library_call (profile_function_entry_libfunc
, LCT_NORMAL
, VOIDmode
,
6807 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS
,
6809 hard_frame_pointer_rtx
),
6813 if (current_function_profile
)
6816 PROFILE_HOOK (current_function_funcdef_no
);
6820 /* After the display initializations is where the tail-recursion label
6821 should go, if we end up needing one. Ensure we have a NOTE here
6822 since some things (like trampolines) get placed before this. */
6823 tail_recursion_reentry
= emit_note (NOTE_INSN_DELETED
);
6825 /* Evaluate now the sizes of any types declared among the arguments. */
6826 expand_pending_sizes (nreverse (get_pending_sizes ()));
6828 /* Make sure there is a line number after the function entry setup code. */
6829 force_next_line_note ();
6832 /* Undo the effects of init_dummy_function_start. */
6834 expand_dummy_function_end (void)
6836 /* End any sequences that failed to be closed due to syntax errors. */
6837 while (in_sequence_p ())
6840 /* Outside function body, can't compute type's actual size
6841 until next function's body starts. */
6843 free_after_parsing (cfun
);
6844 free_after_compilation (cfun
);
6848 /* Call DOIT for each hard register used as a return value from
6849 the current function. */
6852 diddle_return_value (void (*doit
) (rtx
, void *), void *arg
)
6854 rtx outgoing
= current_function_return_rtx
;
6859 if (GET_CODE (outgoing
) == REG
)
6860 (*doit
) (outgoing
, arg
);
6861 else if (GET_CODE (outgoing
) == PARALLEL
)
6865 for (i
= 0; i
< XVECLEN (outgoing
, 0); i
++)
6867 rtx x
= XEXP (XVECEXP (outgoing
, 0, i
), 0);
6869 if (GET_CODE (x
) == REG
&& REGNO (x
) < FIRST_PSEUDO_REGISTER
)
6876 do_clobber_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
6878 emit_insn (gen_rtx_CLOBBER (VOIDmode
, reg
));
6882 clobber_return_register (void)
6884 diddle_return_value (do_clobber_return_reg
, NULL
);
6886 /* In case we do use pseudo to return value, clobber it too. */
6887 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
6889 tree decl_result
= DECL_RESULT (current_function_decl
);
6890 rtx decl_rtl
= DECL_RTL (decl_result
);
6891 if (REG_P (decl_rtl
) && REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
)
6893 do_clobber_return_reg (decl_rtl
, NULL
);
6899 do_use_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
6901 emit_insn (gen_rtx_USE (VOIDmode
, reg
));
6905 use_return_register (void)
6907 diddle_return_value (do_use_return_reg
, NULL
);
6910 static GTY(()) rtx initial_trampoline
;
6912 /* Generate RTL for the end of the current function. */
6915 expand_function_end (void)
6920 finish_expr_for_function ();
6922 /* If arg_pointer_save_area was referenced only from a nested
6923 function, we will not have initialized it yet. Do that now. */
6924 if (arg_pointer_save_area
&& ! cfun
->arg_pointer_save_area_init
)
6925 get_arg_pointer_save_area (cfun
);
6927 #ifdef NON_SAVING_SETJMP
6928 /* Don't put any variables in registers if we call setjmp
6929 on a machine that fails to restore the registers. */
6930 if (NON_SAVING_SETJMP
&& current_function_calls_setjmp
)
6932 if (DECL_INITIAL (current_function_decl
) != error_mark_node
)
6933 setjmp_protect (DECL_INITIAL (current_function_decl
));
6935 setjmp_protect_args ();
6939 /* Initialize any trampolines required by this function. */
6940 for (link
= trampoline_list
; link
; link
= TREE_CHAIN (link
))
6942 tree function
= TREE_PURPOSE (link
);
6943 rtx context ATTRIBUTE_UNUSED
= lookup_static_chain (function
);
6944 rtx tramp
= RTL_EXPR_RTL (TREE_VALUE (link
));
6945 #ifdef TRAMPOLINE_TEMPLATE
6950 #ifdef TRAMPOLINE_TEMPLATE
6951 /* First make sure this compilation has a template for
6952 initializing trampolines. */
6953 if (initial_trampoline
== 0)
6956 = gen_rtx_MEM (BLKmode
, assemble_trampoline_template ());
6957 set_mem_align (initial_trampoline
, TRAMPOLINE_ALIGNMENT
);
6961 /* Generate insns to initialize the trampoline. */
6963 tramp
= round_trampoline_addr (XEXP (tramp
, 0));
6964 #ifdef TRAMPOLINE_TEMPLATE
6965 blktramp
= replace_equiv_address (initial_trampoline
, tramp
);
6966 emit_block_move (blktramp
, initial_trampoline
,
6967 GEN_INT (TRAMPOLINE_SIZE
), BLOCK_OP_NORMAL
);
6969 trampolines_created
= 1;
6970 INITIALIZE_TRAMPOLINE (tramp
, XEXP (DECL_RTL (function
), 0), context
);
6974 /* Put those insns at entry to the containing function (this one). */
6975 emit_insn_before (seq
, tail_recursion_reentry
);
6978 /* If we are doing stack checking and this function makes calls,
6979 do a stack probe at the start of the function to ensure we have enough
6980 space for another stack frame. */
6981 if (flag_stack_check
&& ! STACK_CHECK_BUILTIN
)
6985 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
6986 if (GET_CODE (insn
) == CALL_INSN
)
6989 probe_stack_range (STACK_CHECK_PROTECT
,
6990 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
));
6993 emit_insn_before (seq
, tail_recursion_reentry
);
6998 /* Possibly warn about unused parameters. */
6999 if (warn_unused_parameter
)
7003 for (decl
= DECL_ARGUMENTS (current_function_decl
);
7004 decl
; decl
= TREE_CHAIN (decl
))
7005 if (! TREE_USED (decl
) && TREE_CODE (decl
) == PARM_DECL
7006 && DECL_NAME (decl
) && ! DECL_ARTIFICIAL (decl
))
7007 warning ("%Junused parameter '%D'", decl
, decl
);
7010 /* Delete handlers for nonlocal gotos if nothing uses them. */
7011 if (nonlocal_goto_handler_slots
!= 0
7012 && ! current_function_has_nonlocal_label
)
7015 /* End any sequences that failed to be closed due to syntax errors. */
7016 while (in_sequence_p ())
7019 /* Outside function body, can't compute type's actual size
7020 until next function's body starts. */
7021 immediate_size_expand
--;
7023 clear_pending_stack_adjust ();
7024 do_pending_stack_adjust ();
7026 /* @@@ This is a kludge. We want to ensure that instructions that
7027 may trap are not moved into the epilogue by scheduling, because
7028 we don't always emit unwind information for the epilogue.
7029 However, not all machine descriptions define a blockage insn, so
7030 emit an ASM_INPUT to act as one. */
7031 if (flag_non_call_exceptions
)
7032 emit_insn (gen_rtx_ASM_INPUT (VOIDmode
, ""));
7034 /* Mark the end of the function body.
7035 If control reaches this insn, the function can drop through
7036 without returning a value. */
7037 emit_note (NOTE_INSN_FUNCTION_END
);
7039 /* Must mark the last line number note in the function, so that the test
7040 coverage code can avoid counting the last line twice. This just tells
7041 the code to ignore the immediately following line note, since there
7042 already exists a copy of this note somewhere above. This line number
7043 note is still needed for debugging though, so we can't delete it. */
7044 if (flag_test_coverage
)
7045 emit_note (NOTE_INSN_REPEATED_LINE_NUMBER
);
7047 /* Output a linenumber for the end of the function.
7048 SDB depends on this. */
7049 force_next_line_note ();
7050 emit_line_note (input_location
);
7052 /* Before the return label (if any), clobber the return
7053 registers so that they are not propagated live to the rest of
7054 the function. This can only happen with functions that drop
7055 through; if there had been a return statement, there would
7056 have either been a return rtx, or a jump to the return label.
7058 We delay actual code generation after the current_function_value_rtx
7060 clobber_after
= get_last_insn ();
7062 /* Output the label for the actual return from the function,
7063 if one is expected. This happens either because a function epilogue
7064 is used instead of a return instruction, or because a return was done
7065 with a goto in order to run local cleanups, or because of pcc-style
7066 structure returning. */
7068 emit_label (return_label
);
7070 if (current_function_instrument_entry_exit
)
7072 rtx fun
= DECL_RTL (current_function_decl
);
7073 if (GET_CODE (fun
) == MEM
)
7074 fun
= XEXP (fun
, 0);
7077 emit_library_call (profile_function_exit_libfunc
, LCT_NORMAL
, VOIDmode
,
7079 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS
,
7081 hard_frame_pointer_rtx
),
7085 /* Let except.c know where it should emit the call to unregister
7086 the function context for sjlj exceptions. */
7087 if (flag_exceptions
&& USING_SJLJ_EXCEPTIONS
)
7088 sjlj_emit_function_exit_after (get_last_insn ());
7090 /* If we had calls to alloca, and this machine needs
7091 an accurate stack pointer to exit the function,
7092 insert some code to save and restore the stack pointer. */
7093 if (! EXIT_IGNORE_STACK
7094 && current_function_calls_alloca
)
7098 emit_stack_save (SAVE_FUNCTION
, &tem
, parm_birth_insn
);
7099 emit_stack_restore (SAVE_FUNCTION
, tem
, NULL_RTX
);
7102 /* If scalar return value was computed in a pseudo-reg, or was a named
7103 return value that got dumped to the stack, copy that to the hard
7105 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
7107 tree decl_result
= DECL_RESULT (current_function_decl
);
7108 rtx decl_rtl
= DECL_RTL (decl_result
);
7110 if (REG_P (decl_rtl
)
7111 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
7112 : DECL_REGISTER (decl_result
))
7114 rtx real_decl_rtl
= current_function_return_rtx
;
7116 /* This should be set in assign_parms. */
7117 if (! REG_FUNCTION_VALUE_P (real_decl_rtl
))
7120 /* If this is a BLKmode structure being returned in registers,
7121 then use the mode computed in expand_return. Note that if
7122 decl_rtl is memory, then its mode may have been changed,
7123 but that current_function_return_rtx has not. */
7124 if (GET_MODE (real_decl_rtl
) == BLKmode
)
7125 PUT_MODE (real_decl_rtl
, GET_MODE (decl_rtl
));
7127 /* If a named return value dumped decl_return to memory, then
7128 we may need to re-do the PROMOTE_MODE signed/unsigned
7130 if (GET_MODE (real_decl_rtl
) != GET_MODE (decl_rtl
))
7132 int unsignedp
= TREE_UNSIGNED (TREE_TYPE (decl_result
));
7134 if (targetm
.calls
.promote_function_return (TREE_TYPE (current_function_decl
)))
7135 promote_mode (TREE_TYPE (decl_result
), GET_MODE (decl_rtl
),
7138 convert_move (real_decl_rtl
, decl_rtl
, unsignedp
);
7140 else if (GET_CODE (real_decl_rtl
) == PARALLEL
)
7142 /* If expand_function_start has created a PARALLEL for decl_rtl,
7143 move the result to the real return registers. Otherwise, do
7144 a group load from decl_rtl for a named return. */
7145 if (GET_CODE (decl_rtl
) == PARALLEL
)
7146 emit_group_move (real_decl_rtl
, decl_rtl
);
7148 emit_group_load (real_decl_rtl
, decl_rtl
,
7149 TREE_TYPE (decl_result
),
7150 int_size_in_bytes (TREE_TYPE (decl_result
)));
7153 emit_move_insn (real_decl_rtl
, decl_rtl
);
7157 /* If returning a structure, arrange to return the address of the value
7158 in a place where debuggers expect to find it.
7160 If returning a structure PCC style,
7161 the caller also depends on this value.
7162 And current_function_returns_pcc_struct is not necessarily set. */
7163 if (current_function_returns_struct
7164 || current_function_returns_pcc_struct
)
7167 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl
)), 0);
7168 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
7169 #ifdef FUNCTION_OUTGOING_VALUE
7171 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type
),
7172 current_function_decl
);
7175 = FUNCTION_VALUE (build_pointer_type (type
), current_function_decl
);
7178 /* Mark this as a function return value so integrate will delete the
7179 assignment and USE below when inlining this function. */
7180 REG_FUNCTION_VALUE_P (outgoing
) = 1;
7182 /* The address may be ptr_mode and OUTGOING may be Pmode. */
7183 value_address
= convert_memory_address (GET_MODE (outgoing
),
7186 emit_move_insn (outgoing
, value_address
);
7188 /* Show return register used to hold result (in this case the address
7190 current_function_return_rtx
= outgoing
;
7193 /* If this is an implementation of throw, do what's necessary to
7194 communicate between __builtin_eh_return and the epilogue. */
7195 expand_eh_return ();
7197 /* Emit the actual code to clobber return register. */
7202 clobber_return_register ();
7206 after
= emit_insn_after (seq
, clobber_after
);
7208 if (clobber_after
!= after
)
7209 cfun
->x_clobber_return_insn
= after
;
7212 /* Output the label for the naked return from the function, if one is
7213 expected. This is currently used only by __builtin_return. */
7214 if (naked_return_label
)
7215 emit_label (naked_return_label
);
7217 /* ??? This should no longer be necessary since stupid is no longer with
7218 us, but there are some parts of the compiler (eg reload_combine, and
7219 sh mach_dep_reorg) that still try and compute their own lifetime info
7220 instead of using the general framework. */
7221 use_return_register ();
7223 /* Fix up any gotos that jumped out to the outermost
7224 binding level of the function.
7225 Must follow emitting RETURN_LABEL. */
7227 /* If you have any cleanups to do at this point,
7228 and they need to create temporary variables,
7229 then you will lose. */
7230 expand_fixups (get_insns ());
7234 get_arg_pointer_save_area (struct function
*f
)
7236 rtx ret
= f
->x_arg_pointer_save_area
;
7240 ret
= assign_stack_local_1 (Pmode
, GET_MODE_SIZE (Pmode
), 0, f
);
7241 f
->x_arg_pointer_save_area
= ret
;
7244 if (f
== cfun
&& ! f
->arg_pointer_save_area_init
)
7248 /* Save the arg pointer at the beginning of the function. The
7249 generated stack slot may not be a valid memory address, so we
7250 have to check it and fix it if necessary. */
7252 emit_move_insn (validize_mem (ret
), virtual_incoming_args_rtx
);
7256 push_topmost_sequence ();
7257 emit_insn_after (seq
, get_insns ());
7258 pop_topmost_sequence ();
7264 /* Extend a vector that records the INSN_UIDs of INSNS
7265 (a list of one or more insns). */
7268 record_insns (rtx insns
, varray_type
*vecp
)
7275 while (tmp
!= NULL_RTX
)
7278 tmp
= NEXT_INSN (tmp
);
7281 i
= VARRAY_SIZE (*vecp
);
7282 VARRAY_GROW (*vecp
, i
+ len
);
7284 while (tmp
!= NULL_RTX
)
7286 VARRAY_INT (*vecp
, i
) = INSN_UID (tmp
);
7288 tmp
= NEXT_INSN (tmp
);
7292 /* Set the locator of the insn chain starting at INSN to LOC. */
7294 set_insn_locators (rtx insn
, int loc
)
7296 while (insn
!= NULL_RTX
)
7299 INSN_LOCATOR (insn
) = loc
;
7300 insn
= NEXT_INSN (insn
);
7304 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
7305 be running after reorg, SEQUENCE rtl is possible. */
7308 contains (rtx insn
, varray_type vec
)
7312 if (GET_CODE (insn
) == INSN
7313 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
7316 for (i
= XVECLEN (PATTERN (insn
), 0) - 1; i
>= 0; i
--)
7317 for (j
= VARRAY_SIZE (vec
) - 1; j
>= 0; --j
)
7318 if (INSN_UID (XVECEXP (PATTERN (insn
), 0, i
)) == VARRAY_INT (vec
, j
))
7324 for (j
= VARRAY_SIZE (vec
) - 1; j
>= 0; --j
)
7325 if (INSN_UID (insn
) == VARRAY_INT (vec
, j
))
7332 prologue_epilogue_contains (rtx insn
)
7334 if (contains (insn
, prologue
))
7336 if (contains (insn
, epilogue
))
7342 sibcall_epilogue_contains (rtx insn
)
7344 if (sibcall_epilogue
)
7345 return contains (insn
, sibcall_epilogue
);
7350 /* Insert gen_return at the end of block BB. This also means updating
7351 block_for_insn appropriately. */
7354 emit_return_into_block (basic_block bb
, rtx line_note
)
7356 emit_jump_insn_after (gen_return (), BB_END (bb
));
7358 emit_note_copy_after (line_note
, PREV_INSN (BB_END (bb
)));
7360 #endif /* HAVE_return */
7362 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7364 /* These functions convert the epilogue into a variant that does not modify the
7365 stack pointer. This is used in cases where a function returns an object
7366 whose size is not known until it is computed. The called function leaves the
7367 object on the stack, leaves the stack depressed, and returns a pointer to
7370 What we need to do is track all modifications and references to the stack
7371 pointer, deleting the modifications and changing the references to point to
7372 the location the stack pointer would have pointed to had the modifications
7375 These functions need to be portable so we need to make as few assumptions
7376 about the epilogue as we can. However, the epilogue basically contains
7377 three things: instructions to reset the stack pointer, instructions to
7378 reload registers, possibly including the frame pointer, and an
7379 instruction to return to the caller.
7381 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7382 We also make no attempt to validate the insns we make since if they are
7383 invalid, we probably can't do anything valid. The intent is that these
7384 routines get "smarter" as more and more machines start to use them and
7385 they try operating on different epilogues.
7387 We use the following structure to track what the part of the epilogue that
7388 we've already processed has done. We keep two copies of the SP equivalence,
7389 one for use during the insn we are processing and one for use in the next
7390 insn. The difference is because one part of a PARALLEL may adjust SP
7391 and the other may use it. */
7395 rtx sp_equiv_reg
; /* REG that SP is set from, perhaps SP. */
7396 HOST_WIDE_INT sp_offset
; /* Offset from SP_EQUIV_REG of present SP. */
7397 rtx new_sp_equiv_reg
; /* REG to be used at end of insn. */
7398 HOST_WIDE_INT new_sp_offset
; /* Offset to be used at end of insn. */
7399 rtx equiv_reg_src
; /* If nonzero, the value that SP_EQUIV_REG
7400 should be set to once we no longer need
7402 rtx const_equiv
[FIRST_PSEUDO_REGISTER
]; /* Any known constant equivalences
7406 static void handle_epilogue_set (rtx
, struct epi_info
*);
7407 static void update_epilogue_consts (rtx
, rtx
, void *);
7408 static void emit_equiv_load (struct epi_info
*);
7410 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
7411 no modifications to the stack pointer. Return the new list of insns. */
7414 keep_stack_depressed (rtx insns
)
7417 struct epi_info info
;
7420 /* If the epilogue is just a single instruction, it must be OK as is. */
7421 if (NEXT_INSN (insns
) == NULL_RTX
)
7424 /* Otherwise, start a sequence, initialize the information we have, and
7425 process all the insns we were given. */
7428 info
.sp_equiv_reg
= stack_pointer_rtx
;
7430 info
.equiv_reg_src
= 0;
7432 for (j
= 0; j
< FIRST_PSEUDO_REGISTER
; j
++)
7433 info
.const_equiv
[j
] = 0;
7437 while (insn
!= NULL_RTX
)
7439 next
= NEXT_INSN (insn
);
7448 /* If this insn references the register that SP is equivalent to and
7449 we have a pending load to that register, we must force out the load
7450 first and then indicate we no longer know what SP's equivalent is. */
7451 if (info
.equiv_reg_src
!= 0
7452 && reg_referenced_p (info
.sp_equiv_reg
, PATTERN (insn
)))
7454 emit_equiv_load (&info
);
7455 info
.sp_equiv_reg
= 0;
7458 info
.new_sp_equiv_reg
= info
.sp_equiv_reg
;
7459 info
.new_sp_offset
= info
.sp_offset
;
7461 /* If this is a (RETURN) and the return address is on the stack,
7462 update the address and change to an indirect jump. */
7463 if (GET_CODE (PATTERN (insn
)) == RETURN
7464 || (GET_CODE (PATTERN (insn
)) == PARALLEL
7465 && GET_CODE (XVECEXP (PATTERN (insn
), 0, 0)) == RETURN
))
7467 rtx retaddr
= INCOMING_RETURN_ADDR_RTX
;
7469 HOST_WIDE_INT offset
= 0;
7470 rtx jump_insn
, jump_set
;
7472 /* If the return address is in a register, we can emit the insn
7473 unchanged. Otherwise, it must be a MEM and we see what the
7474 base register and offset are. In any case, we have to emit any
7475 pending load to the equivalent reg of SP, if any. */
7476 if (GET_CODE (retaddr
) == REG
)
7478 emit_equiv_load (&info
);
7483 else if (GET_CODE (retaddr
) == MEM
7484 && GET_CODE (XEXP (retaddr
, 0)) == REG
)
7485 base
= gen_rtx_REG (Pmode
, REGNO (XEXP (retaddr
, 0))), offset
= 0;
7486 else if (GET_CODE (retaddr
) == MEM
7487 && GET_CODE (XEXP (retaddr
, 0)) == PLUS
7488 && GET_CODE (XEXP (XEXP (retaddr
, 0), 0)) == REG
7489 && GET_CODE (XEXP (XEXP (retaddr
, 0), 1)) == CONST_INT
)
7491 base
= gen_rtx_REG (Pmode
, REGNO (XEXP (XEXP (retaddr
, 0), 0)));
7492 offset
= INTVAL (XEXP (XEXP (retaddr
, 0), 1));
7497 /* If the base of the location containing the return pointer
7498 is SP, we must update it with the replacement address. Otherwise,
7499 just build the necessary MEM. */
7500 retaddr
= plus_constant (base
, offset
);
7501 if (base
== stack_pointer_rtx
)
7502 retaddr
= simplify_replace_rtx (retaddr
, stack_pointer_rtx
,
7503 plus_constant (info
.sp_equiv_reg
,
7506 retaddr
= gen_rtx_MEM (Pmode
, retaddr
);
7508 /* If there is a pending load to the equivalent register for SP
7509 and we reference that register, we must load our address into
7510 a scratch register and then do that load. */
7511 if (info
.equiv_reg_src
7512 && reg_overlap_mentioned_p (info
.equiv_reg_src
, retaddr
))
7517 for (regno
= 0; regno
< FIRST_PSEUDO_REGISTER
; regno
++)
7518 if (HARD_REGNO_MODE_OK (regno
, Pmode
)
7519 && !fixed_regs
[regno
]
7520 && TEST_HARD_REG_BIT (regs_invalidated_by_call
, regno
)
7521 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR
->global_live_at_start
,
7523 && !refers_to_regno_p (regno
,
7524 regno
+ hard_regno_nregs
[regno
]
7526 info
.equiv_reg_src
, NULL
)
7527 && info
.const_equiv
[regno
] == 0)
7530 if (regno
== FIRST_PSEUDO_REGISTER
)
7533 reg
= gen_rtx_REG (Pmode
, regno
);
7534 emit_move_insn (reg
, retaddr
);
7538 emit_equiv_load (&info
);
7539 jump_insn
= emit_jump_insn (gen_indirect_jump (retaddr
));
7541 /* Show the SET in the above insn is a RETURN. */
7542 jump_set
= single_set (jump_insn
);
7546 SET_IS_RETURN_P (jump_set
) = 1;
7549 /* If SP is not mentioned in the pattern and its equivalent register, if
7550 any, is not modified, just emit it. Otherwise, if neither is set,
7551 replace the reference to SP and emit the insn. If none of those are
7552 true, handle each SET individually. */
7553 else if (!reg_mentioned_p (stack_pointer_rtx
, PATTERN (insn
))
7554 && (info
.sp_equiv_reg
== stack_pointer_rtx
7555 || !reg_set_p (info
.sp_equiv_reg
, insn
)))
7557 else if (! reg_set_p (stack_pointer_rtx
, insn
)
7558 && (info
.sp_equiv_reg
== stack_pointer_rtx
7559 || !reg_set_p (info
.sp_equiv_reg
, insn
)))
7561 if (! validate_replace_rtx (stack_pointer_rtx
,
7562 plus_constant (info
.sp_equiv_reg
,
7569 else if (GET_CODE (PATTERN (insn
)) == SET
)
7570 handle_epilogue_set (PATTERN (insn
), &info
);
7571 else if (GET_CODE (PATTERN (insn
)) == PARALLEL
)
7573 for (j
= 0; j
< XVECLEN (PATTERN (insn
), 0); j
++)
7574 if (GET_CODE (XVECEXP (PATTERN (insn
), 0, j
)) == SET
)
7575 handle_epilogue_set (XVECEXP (PATTERN (insn
), 0, j
), &info
);
7580 info
.sp_equiv_reg
= info
.new_sp_equiv_reg
;
7581 info
.sp_offset
= info
.new_sp_offset
;
7583 /* Now update any constants this insn sets. */
7584 note_stores (PATTERN (insn
), update_epilogue_consts
, &info
);
7588 insns
= get_insns ();
7593 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7594 structure that contains information about what we've seen so far. We
7595 process this SET by either updating that data or by emitting one or
7599 handle_epilogue_set (rtx set
, struct epi_info
*p
)
7601 /* First handle the case where we are setting SP. Record what it is being
7602 set from. If unknown, abort. */
7603 if (reg_set_p (stack_pointer_rtx
, set
))
7605 if (SET_DEST (set
) != stack_pointer_rtx
)
7608 if (GET_CODE (SET_SRC (set
)) == PLUS
)
7610 p
->new_sp_equiv_reg
= XEXP (SET_SRC (set
), 0);
7611 if (GET_CODE (XEXP (SET_SRC (set
), 1)) == CONST_INT
)
7612 p
->new_sp_offset
= INTVAL (XEXP (SET_SRC (set
), 1));
7613 else if (GET_CODE (XEXP (SET_SRC (set
), 1)) == REG
7614 && REGNO (XEXP (SET_SRC (set
), 1)) < FIRST_PSEUDO_REGISTER
7615 && p
->const_equiv
[REGNO (XEXP (SET_SRC (set
), 1))] != 0)
7617 = INTVAL (p
->const_equiv
[REGNO (XEXP (SET_SRC (set
), 1))]);
7622 p
->new_sp_equiv_reg
= SET_SRC (set
), p
->new_sp_offset
= 0;
7624 /* If we are adjusting SP, we adjust from the old data. */
7625 if (p
->new_sp_equiv_reg
== stack_pointer_rtx
)
7627 p
->new_sp_equiv_reg
= p
->sp_equiv_reg
;
7628 p
->new_sp_offset
+= p
->sp_offset
;
7631 if (p
->new_sp_equiv_reg
== 0 || GET_CODE (p
->new_sp_equiv_reg
) != REG
)
7637 /* Next handle the case where we are setting SP's equivalent register.
7638 If we already have a value to set it to, abort. We could update, but
7639 there seems little point in handling that case. Note that we have
7640 to allow for the case where we are setting the register set in
7641 the previous part of a PARALLEL inside a single insn. But use the
7642 old offset for any updates within this insn. We must allow for the case
7643 where the register is being set in a different (usually wider) mode than
7645 else if (p
->new_sp_equiv_reg
!= 0 && reg_set_p (p
->new_sp_equiv_reg
, set
))
7647 if (p
->equiv_reg_src
!= 0
7648 || GET_CODE (p
->new_sp_equiv_reg
) != REG
7649 || GET_CODE (SET_DEST (set
)) != REG
7650 || GET_MODE_BITSIZE (GET_MODE (SET_DEST (set
))) > BITS_PER_WORD
7651 || REGNO (p
->new_sp_equiv_reg
) != REGNO (SET_DEST (set
)))
7655 = simplify_replace_rtx (SET_SRC (set
), stack_pointer_rtx
,
7656 plus_constant (p
->sp_equiv_reg
,
7660 /* Otherwise, replace any references to SP in the insn to its new value
7661 and emit the insn. */
7664 SET_SRC (set
) = simplify_replace_rtx (SET_SRC (set
), stack_pointer_rtx
,
7665 plus_constant (p
->sp_equiv_reg
,
7667 SET_DEST (set
) = simplify_replace_rtx (SET_DEST (set
), stack_pointer_rtx
,
7668 plus_constant (p
->sp_equiv_reg
,
7674 /* Update the tracking information for registers set to constants. */
7677 update_epilogue_consts (rtx dest
, rtx x
, void *data
)
7679 struct epi_info
*p
= (struct epi_info
*) data
;
7682 if (GET_CODE (dest
) != REG
|| REGNO (dest
) >= FIRST_PSEUDO_REGISTER
)
7685 /* If we are either clobbering a register or doing a partial set,
7686 show we don't know the value. */
7687 else if (GET_CODE (x
) == CLOBBER
|| ! rtx_equal_p (dest
, SET_DEST (x
)))
7688 p
->const_equiv
[REGNO (dest
)] = 0;
7690 /* If we are setting it to a constant, record that constant. */
7691 else if (GET_CODE (SET_SRC (x
)) == CONST_INT
)
7692 p
->const_equiv
[REGNO (dest
)] = SET_SRC (x
);
7694 /* If this is a binary operation between a register we have been tracking
7695 and a constant, see if we can compute a new constant value. */
7696 else if (ARITHMETIC_P (SET_SRC (x
))
7697 && GET_CODE (XEXP (SET_SRC (x
), 0)) == REG
7698 && REGNO (XEXP (SET_SRC (x
), 0)) < FIRST_PSEUDO_REGISTER
7699 && p
->const_equiv
[REGNO (XEXP (SET_SRC (x
), 0))] != 0
7700 && GET_CODE (XEXP (SET_SRC (x
), 1)) == CONST_INT
7701 && 0 != (new = simplify_binary_operation
7702 (GET_CODE (SET_SRC (x
)), GET_MODE (dest
),
7703 p
->const_equiv
[REGNO (XEXP (SET_SRC (x
), 0))],
7704 XEXP (SET_SRC (x
), 1)))
7705 && GET_CODE (new) == CONST_INT
)
7706 p
->const_equiv
[REGNO (dest
)] = new;
7708 /* Otherwise, we can't do anything with this value. */
7710 p
->const_equiv
[REGNO (dest
)] = 0;
7713 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7716 emit_equiv_load (struct epi_info
*p
)
7718 if (p
->equiv_reg_src
!= 0)
7720 rtx dest
= p
->sp_equiv_reg
;
7722 if (GET_MODE (p
->equiv_reg_src
) != GET_MODE (dest
))
7723 dest
= gen_rtx_REG (GET_MODE (p
->equiv_reg_src
),
7724 REGNO (p
->sp_equiv_reg
));
7726 emit_move_insn (dest
, p
->equiv_reg_src
);
7727 p
->equiv_reg_src
= 0;
7732 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7733 this into place with notes indicating where the prologue ends and where
7734 the epilogue begins. Update the basic block information when possible. */
7737 thread_prologue_and_epilogue_insns (rtx f ATTRIBUTE_UNUSED
)
7741 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7744 #ifdef HAVE_prologue
7745 rtx prologue_end
= NULL_RTX
;
7747 #if defined (HAVE_epilogue) || defined(HAVE_return)
7748 rtx epilogue_end
= NULL_RTX
;
7751 #ifdef HAVE_prologue
7755 seq
= gen_prologue ();
7758 /* Retain a map of the prologue insns. */
7759 record_insns (seq
, &prologue
);
7760 prologue_end
= emit_note (NOTE_INSN_PROLOGUE_END
);
7764 set_insn_locators (seq
, prologue_locator
);
7766 /* Can't deal with multiple successors of the entry block
7767 at the moment. Function should always have at least one
7769 if (!ENTRY_BLOCK_PTR
->succ
|| ENTRY_BLOCK_PTR
->succ
->succ_next
)
7772 insert_insn_on_edge (seq
, ENTRY_BLOCK_PTR
->succ
);
7777 /* If the exit block has no non-fake predecessors, we don't need
7779 for (e
= EXIT_BLOCK_PTR
->pred
; e
; e
= e
->pred_next
)
7780 if ((e
->flags
& EDGE_FAKE
) == 0)
7786 if (optimize
&& HAVE_return
)
7788 /* If we're allowed to generate a simple return instruction,
7789 then by definition we don't need a full epilogue. Examine
7790 the block that falls through to EXIT. If it does not
7791 contain any code, examine its predecessors and try to
7792 emit (conditional) return instructions. */
7798 for (e
= EXIT_BLOCK_PTR
->pred
; e
; e
= e
->pred_next
)
7799 if (e
->flags
& EDGE_FALLTHRU
)
7805 /* Verify that there are no active instructions in the last block. */
7806 label
= BB_END (last
);
7807 while (label
&& GET_CODE (label
) != CODE_LABEL
)
7809 if (active_insn_p (label
))
7811 label
= PREV_INSN (label
);
7814 if (BB_HEAD (last
) == label
&& GET_CODE (label
) == CODE_LABEL
)
7816 rtx epilogue_line_note
= NULL_RTX
;
7818 /* Locate the line number associated with the closing brace,
7819 if we can find one. */
7820 for (seq
= get_last_insn ();
7821 seq
&& ! active_insn_p (seq
);
7822 seq
= PREV_INSN (seq
))
7823 if (GET_CODE (seq
) == NOTE
&& NOTE_LINE_NUMBER (seq
) > 0)
7825 epilogue_line_note
= seq
;
7829 for (e
= last
->pred
; e
; e
= e_next
)
7831 basic_block bb
= e
->src
;
7834 e_next
= e
->pred_next
;
7835 if (bb
== ENTRY_BLOCK_PTR
)
7839 if ((GET_CODE (jump
) != JUMP_INSN
) || JUMP_LABEL (jump
) != label
)
7842 /* If we have an unconditional jump, we can replace that
7843 with a simple return instruction. */
7844 if (simplejump_p (jump
))
7846 emit_return_into_block (bb
, epilogue_line_note
);
7850 /* If we have a conditional jump, we can try to replace
7851 that with a conditional return instruction. */
7852 else if (condjump_p (jump
))
7854 if (! redirect_jump (jump
, 0, 0))
7857 /* If this block has only one successor, it both jumps
7858 and falls through to the fallthru block, so we can't
7860 if (bb
->succ
->succ_next
== NULL
)
7866 /* Fix up the CFG for the successful change we just made. */
7867 redirect_edge_succ (e
, EXIT_BLOCK_PTR
);
7870 /* Emit a return insn for the exit fallthru block. Whether
7871 this is still reachable will be determined later. */
7873 emit_barrier_after (BB_END (last
));
7874 emit_return_into_block (last
, epilogue_line_note
);
7875 epilogue_end
= BB_END (last
);
7876 last
->succ
->flags
&= ~EDGE_FALLTHRU
;
7881 #ifdef HAVE_epilogue
7884 /* Find the edge that falls through to EXIT. Other edges may exist
7885 due to RETURN instructions, but those don't need epilogues.
7886 There really shouldn't be a mixture -- either all should have
7887 been converted or none, however... */
7889 for (e
= EXIT_BLOCK_PTR
->pred
; e
; e
= e
->pred_next
)
7890 if (e
->flags
& EDGE_FALLTHRU
)
7896 epilogue_end
= emit_note (NOTE_INSN_EPILOGUE_BEG
);
7898 seq
= gen_epilogue ();
7900 #ifdef INCOMING_RETURN_ADDR_RTX
7901 /* If this function returns with the stack depressed and we can support
7902 it, massage the epilogue to actually do that. */
7903 if (TREE_CODE (TREE_TYPE (current_function_decl
)) == FUNCTION_TYPE
7904 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl
)))
7905 seq
= keep_stack_depressed (seq
);
7908 emit_jump_insn (seq
);
7910 /* Retain a map of the epilogue insns. */
7911 record_insns (seq
, &epilogue
);
7912 set_insn_locators (seq
, epilogue_locator
);
7917 insert_insn_on_edge (seq
, e
);
7924 commit_edge_insertions ();
7926 #ifdef HAVE_sibcall_epilogue
7927 /* Emit sibling epilogues before any sibling call sites. */
7928 for (e
= EXIT_BLOCK_PTR
->pred
; e
; e
= e
->pred_next
)
7930 basic_block bb
= e
->src
;
7931 rtx insn
= BB_END (bb
);
7935 if (GET_CODE (insn
) != CALL_INSN
7936 || ! SIBLING_CALL_P (insn
))
7940 emit_insn (gen_sibcall_epilogue ());
7944 /* Retain a map of the epilogue insns. Used in life analysis to
7945 avoid getting rid of sibcall epilogue insns. Do this before we
7946 actually emit the sequence. */
7947 record_insns (seq
, &sibcall_epilogue
);
7948 set_insn_locators (seq
, epilogue_locator
);
7950 i
= PREV_INSN (insn
);
7951 newinsn
= emit_insn_before (seq
, insn
);
7955 #ifdef HAVE_prologue
7956 /* This is probably all useless now that we use locators. */
7961 /* GDB handles `break f' by setting a breakpoint on the first
7962 line note after the prologue. Which means (1) that if
7963 there are line number notes before where we inserted the
7964 prologue we should move them, and (2) we should generate a
7965 note before the end of the first basic block, if there isn't
7968 ??? This behavior is completely broken when dealing with
7969 multiple entry functions. We simply place the note always
7970 into first basic block and let alternate entry points
7974 for (insn
= prologue_end
; insn
; insn
= prev
)
7976 prev
= PREV_INSN (insn
);
7977 if (GET_CODE (insn
) == NOTE
&& NOTE_LINE_NUMBER (insn
) > 0)
7979 /* Note that we cannot reorder the first insn in the
7980 chain, since rest_of_compilation relies on that
7981 remaining constant. */
7984 reorder_insns (insn
, insn
, prologue_end
);
7988 /* Find the last line number note in the first block. */
7989 for (insn
= BB_END (ENTRY_BLOCK_PTR
->next_bb
);
7990 insn
!= prologue_end
&& insn
;
7991 insn
= PREV_INSN (insn
))
7992 if (GET_CODE (insn
) == NOTE
&& NOTE_LINE_NUMBER (insn
) > 0)
7995 /* If we didn't find one, make a copy of the first line number
7999 for (insn
= next_active_insn (prologue_end
);
8001 insn
= PREV_INSN (insn
))
8002 if (GET_CODE (insn
) == NOTE
&& NOTE_LINE_NUMBER (insn
) > 0)
8004 emit_note_copy_after (insn
, prologue_end
);
8010 #ifdef HAVE_epilogue
8015 /* Similarly, move any line notes that appear after the epilogue.
8016 There is no need, however, to be quite so anal about the existence
8018 for (insn
= epilogue_end
; insn
; insn
= next
)
8020 next
= NEXT_INSN (insn
);
8021 if (GET_CODE (insn
) == NOTE
&& NOTE_LINE_NUMBER (insn
) > 0)
8022 reorder_insns (insn
, insn
, PREV_INSN (epilogue_end
));
8028 /* Reposition the prologue-end and epilogue-begin notes after instruction
8029 scheduling and delayed branch scheduling. */
8032 reposition_prologue_and_epilogue_notes (rtx f ATTRIBUTE_UNUSED
)
8034 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
8035 rtx insn
, last
, note
;
8038 if ((len
= VARRAY_SIZE (prologue
)) > 0)
8042 /* Scan from the beginning until we reach the last prologue insn.
8043 We apparently can't depend on basic_block_{head,end} after
8045 for (insn
= f
; insn
; insn
= NEXT_INSN (insn
))
8047 if (GET_CODE (insn
) == NOTE
)
8049 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_PROLOGUE_END
)
8052 else if (contains (insn
, prologue
))
8062 /* Find the prologue-end note if we haven't already, and
8063 move it to just after the last prologue insn. */
8066 for (note
= last
; (note
= NEXT_INSN (note
));)
8067 if (GET_CODE (note
) == NOTE
8068 && NOTE_LINE_NUMBER (note
) == NOTE_INSN_PROLOGUE_END
)
8072 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
8073 if (GET_CODE (last
) == CODE_LABEL
)
8074 last
= NEXT_INSN (last
);
8075 reorder_insns (note
, note
, last
);
8079 if ((len
= VARRAY_SIZE (epilogue
)) > 0)
8083 /* Scan from the end until we reach the first epilogue insn.
8084 We apparently can't depend on basic_block_{head,end} after
8086 for (insn
= get_last_insn (); insn
; insn
= PREV_INSN (insn
))
8088 if (GET_CODE (insn
) == NOTE
)
8090 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_EPILOGUE_BEG
)
8093 else if (contains (insn
, epilogue
))
8103 /* Find the epilogue-begin note if we haven't already, and
8104 move it to just before the first epilogue insn. */
8107 for (note
= insn
; (note
= PREV_INSN (note
));)
8108 if (GET_CODE (note
) == NOTE
8109 && NOTE_LINE_NUMBER (note
) == NOTE_INSN_EPILOGUE_BEG
)
8113 if (PREV_INSN (last
) != note
)
8114 reorder_insns (note
, note
, PREV_INSN (last
));
8117 #endif /* HAVE_prologue or HAVE_epilogue */
8120 /* Called once, at initialization, to initialize function.c. */
8123 init_function_once (void)
8125 VARRAY_INT_INIT (prologue
, 0, "prologue");
8126 VARRAY_INT_INIT (epilogue
, 0, "epilogue");
8127 VARRAY_INT_INIT (sibcall_epilogue
, 0, "sibcall_epilogue");
8130 /* Returns the name of the current function. */
8132 current_function_name (void)
8134 return lang_hooks
.decl_printable_name (cfun
->decl
, 2);
8137 #include "gt-function.h"