PR optimization/9090
[official-gcc.git] / gcc / function.c
blobfe5394ec036d6ca8e319c39c5ec5ac6a14923f0e
1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
10 version.
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
15 for more details.
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
20 02111-1307, USA. */
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. */
41 #include "config.h"
42 #include "system.h"
43 #include "coretypes.h"
44 #include "tm.h"
45 #include "rtl.h"
46 #include "tree.h"
47 #include "flags.h"
48 #include "except.h"
49 #include "function.h"
50 #include "expr.h"
51 #include "libfuncs.h"
52 #include "regs.h"
53 #include "hard-reg-set.h"
54 #include "insn-config.h"
55 #include "recog.h"
56 #include "output.h"
57 #include "basic-block.h"
58 #include "toplev.h"
59 #include "hashtab.h"
60 #include "ggc.h"
61 #include "tm_p.h"
62 #include "integrate.h"
63 #include "langhooks.h"
65 #ifndef TRAMPOLINE_ALIGNMENT
66 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
67 #endif
69 #ifndef LOCAL_ALIGNMENT
70 #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT
71 #endif
73 /* Some systems use __main in a way incompatible with its use in gcc, in these
74 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
75 give the same symbol without quotes for an alternative entry point. You
76 must define both, or neither. */
77 #ifndef NAME__MAIN
78 #define NAME__MAIN "__main"
79 #endif
81 /* Round a value to the lowest integer less than it that is a multiple of
82 the required alignment. Avoid using division in case the value is
83 negative. Assume the alignment is a power of two. */
84 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
86 /* Similar, but round to the next highest integer that meets the
87 alignment. */
88 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
90 /* NEED_SEPARATE_AP means that we cannot derive ap from the value of fp
91 during rtl generation. If they are different register numbers, this is
92 always true. It may also be true if
93 FIRST_PARM_OFFSET - STARTING_FRAME_OFFSET is not a constant during rtl
94 generation. See fix_lexical_addr for details. */
96 #if ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
97 #define NEED_SEPARATE_AP
98 #endif
100 /* Nonzero if function being compiled doesn't contain any calls
101 (ignoring the prologue and epilogue). This is set prior to
102 local register allocation and is valid for the remaining
103 compiler passes. */
104 int current_function_is_leaf;
106 /* Nonzero if function being compiled doesn't contain any instructions
107 that can throw an exception. This is set prior to final. */
109 int current_function_nothrow;
111 /* Nonzero if function being compiled doesn't modify the stack pointer
112 (ignoring the prologue and epilogue). This is only valid after
113 life_analysis has run. */
114 int current_function_sp_is_unchanging;
116 /* Nonzero if the function being compiled is a leaf function which only
117 uses leaf registers. This is valid after reload (specifically after
118 sched2) and is useful only if the port defines LEAF_REGISTERS. */
119 int current_function_uses_only_leaf_regs;
121 /* Nonzero once virtual register instantiation has been done.
122 assign_stack_local uses frame_pointer_rtx when this is nonzero.
123 calls.c:emit_library_call_value_1 uses it to set up
124 post-instantiation libcalls. */
125 int virtuals_instantiated;
127 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
128 static GTY(()) int funcdef_no;
130 /* These variables hold pointers to functions to create and destroy
131 target specific, per-function data structures. */
132 struct machine_function * (*init_machine_status) PARAMS ((void));
134 /* The FUNCTION_DECL for an inline function currently being expanded. */
135 tree inline_function_decl;
137 /* The currently compiled function. */
138 struct function *cfun = 0;
140 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
141 static GTY(()) varray_type prologue;
142 static GTY(()) varray_type epilogue;
144 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
145 in this function. */
146 static GTY(()) varray_type sibcall_epilogue;
148 /* In order to evaluate some expressions, such as function calls returning
149 structures in memory, we need to temporarily allocate stack locations.
150 We record each allocated temporary in the following structure.
152 Associated with each temporary slot is a nesting level. When we pop up
153 one level, all temporaries associated with the previous level are freed.
154 Normally, all temporaries are freed after the execution of the statement
155 in which they were created. However, if we are inside a ({...}) grouping,
156 the result may be in a temporary and hence must be preserved. If the
157 result could be in a temporary, we preserve it if we can determine which
158 one it is in. If we cannot determine which temporary may contain the
159 result, all temporaries are preserved. A temporary is preserved by
160 pretending it was allocated at the previous nesting level.
162 Automatic variables are also assigned temporary slots, at the nesting
163 level where they are defined. They are marked a "kept" so that
164 free_temp_slots will not free them. */
166 struct temp_slot GTY(())
168 /* Points to next temporary slot. */
169 struct temp_slot *next;
170 /* The rtx to used to reference the slot. */
171 rtx slot;
172 /* The rtx used to represent the address if not the address of the
173 slot above. May be an EXPR_LIST if multiple addresses exist. */
174 rtx address;
175 /* The alignment (in bits) of the slot. */
176 unsigned int align;
177 /* The size, in units, of the slot. */
178 HOST_WIDE_INT size;
179 /* The type of the object in the slot, or zero if it doesn't correspond
180 to a type. We use this to determine whether a slot can be reused.
181 It can be reused if objects of the type of the new slot will always
182 conflict with objects of the type of the old slot. */
183 tree type;
184 /* The value of `sequence_rtl_expr' when this temporary is allocated. */
185 tree rtl_expr;
186 /* Nonzero if this temporary is currently in use. */
187 char in_use;
188 /* Nonzero if this temporary has its address taken. */
189 char addr_taken;
190 /* Nesting level at which this slot is being used. */
191 int level;
192 /* Nonzero if this should survive a call to free_temp_slots. */
193 int keep;
194 /* The offset of the slot from the frame_pointer, including extra space
195 for alignment. This info is for combine_temp_slots. */
196 HOST_WIDE_INT base_offset;
197 /* The size of the slot, including extra space for alignment. This
198 info is for combine_temp_slots. */
199 HOST_WIDE_INT full_size;
202 /* This structure is used to record MEMs or pseudos used to replace VAR, any
203 SUBREGs of VAR, and any MEMs containing VAR as an address. We need to
204 maintain this list in case two operands of an insn were required to match;
205 in that case we must ensure we use the same replacement. */
207 struct fixup_replacement GTY(())
209 rtx old;
210 rtx new;
211 struct fixup_replacement *next;
214 struct insns_for_mem_entry
216 /* A MEM. */
217 rtx key;
218 /* These are the INSNs which reference the MEM. */
219 rtx insns;
222 /* Forward declarations. */
224 static rtx assign_stack_local_1 PARAMS ((enum machine_mode, HOST_WIDE_INT,
225 int, struct function *));
226 static struct temp_slot *find_temp_slot_from_address PARAMS ((rtx));
227 static void put_reg_into_stack PARAMS ((struct function *, rtx, tree,
228 enum machine_mode, enum machine_mode,
229 int, unsigned int, int,
230 htab_t));
231 static void schedule_fixup_var_refs PARAMS ((struct function *, rtx, tree,
232 enum machine_mode,
233 htab_t));
234 static void fixup_var_refs PARAMS ((rtx, enum machine_mode, int, rtx,
235 htab_t));
236 static struct fixup_replacement
237 *find_fixup_replacement PARAMS ((struct fixup_replacement **, rtx));
238 static void fixup_var_refs_insns PARAMS ((rtx, rtx, enum machine_mode,
239 int, int, rtx));
240 static void fixup_var_refs_insns_with_hash
241 PARAMS ((htab_t, rtx,
242 enum machine_mode, int, rtx));
243 static void fixup_var_refs_insn PARAMS ((rtx, rtx, enum machine_mode,
244 int, int, rtx));
245 static void fixup_var_refs_1 PARAMS ((rtx, enum machine_mode, rtx *, rtx,
246 struct fixup_replacement **, rtx));
247 static rtx fixup_memory_subreg PARAMS ((rtx, rtx, enum machine_mode, int));
248 static rtx walk_fixup_memory_subreg PARAMS ((rtx, rtx, enum machine_mode,
249 int));
250 static rtx fixup_stack_1 PARAMS ((rtx, rtx));
251 static void optimize_bit_field PARAMS ((rtx, rtx, rtx *));
252 static void instantiate_decls PARAMS ((tree, int));
253 static void instantiate_decls_1 PARAMS ((tree, int));
254 static void instantiate_decl PARAMS ((rtx, HOST_WIDE_INT, int));
255 static rtx instantiate_new_reg PARAMS ((rtx, HOST_WIDE_INT *));
256 static int instantiate_virtual_regs_1 PARAMS ((rtx *, rtx, int));
257 static void delete_handlers PARAMS ((void));
258 static void pad_to_arg_alignment PARAMS ((struct args_size *, int,
259 struct args_size *));
260 static void pad_below PARAMS ((struct args_size *, enum machine_mode,
261 tree));
262 static rtx round_trampoline_addr PARAMS ((rtx));
263 static rtx adjust_trampoline_addr PARAMS ((rtx));
264 static tree *identify_blocks_1 PARAMS ((rtx, tree *, tree *, tree *));
265 static void reorder_blocks_0 PARAMS ((tree));
266 static void reorder_blocks_1 PARAMS ((rtx, tree, varray_type *));
267 static void reorder_fix_fragments PARAMS ((tree));
268 static tree blocks_nreverse PARAMS ((tree));
269 static int all_blocks PARAMS ((tree, tree *));
270 static tree *get_block_vector PARAMS ((tree, int *));
271 extern tree debug_find_var_in_block_tree PARAMS ((tree, tree));
272 /* We always define `record_insns' even if its not used so that we
273 can always export `prologue_epilogue_contains'. */
274 static void record_insns PARAMS ((rtx, varray_type *)) ATTRIBUTE_UNUSED;
275 static int contains PARAMS ((rtx, varray_type));
276 #ifdef HAVE_return
277 static void emit_return_into_block PARAMS ((basic_block, rtx));
278 #endif
279 static void put_addressof_into_stack PARAMS ((rtx, htab_t));
280 static bool purge_addressof_1 PARAMS ((rtx *, rtx, int, int,
281 htab_t));
282 static void purge_single_hard_subreg_set PARAMS ((rtx));
283 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
284 static rtx keep_stack_depressed PARAMS ((rtx));
285 #endif
286 static int is_addressof PARAMS ((rtx *, void *));
287 static hashval_t insns_for_mem_hash PARAMS ((const void *));
288 static int insns_for_mem_comp PARAMS ((const void *, const void *));
289 static int insns_for_mem_walk PARAMS ((rtx *, void *));
290 static void compute_insns_for_mem PARAMS ((rtx, rtx, htab_t));
291 static void prepare_function_start PARAMS ((void));
292 static void do_clobber_return_reg PARAMS ((rtx, void *));
293 static void do_use_return_reg PARAMS ((rtx, void *));
295 /* Pointer to chain of `struct function' for containing functions. */
296 static GTY(()) struct function *outer_function_chain;
298 /* Given a function decl for a containing function,
299 return the `struct function' for it. */
301 struct function *
302 find_function_data (decl)
303 tree decl;
305 struct function *p;
307 for (p = outer_function_chain; p; p = p->outer)
308 if (p->decl == decl)
309 return p;
311 abort ();
314 /* Save the current context for compilation of a nested function.
315 This is called from language-specific code. The caller should use
316 the enter_nested langhook to save any language-specific state,
317 since this function knows only about language-independent
318 variables. */
320 void
321 push_function_context_to (context)
322 tree context;
324 struct function *p;
326 if (context)
328 if (context == current_function_decl)
329 cfun->contains_functions = 1;
330 else
332 struct function *containing = find_function_data (context);
333 containing->contains_functions = 1;
337 if (cfun == 0)
338 init_dummy_function_start ();
339 p = cfun;
341 p->outer = outer_function_chain;
342 outer_function_chain = p;
343 p->fixup_var_refs_queue = 0;
345 (*lang_hooks.function.enter_nested) (p);
347 cfun = 0;
350 void
351 push_function_context ()
353 push_function_context_to (current_function_decl);
356 /* Restore the last saved context, at the end of a nested function.
357 This function is called from language-specific code. */
359 void
360 pop_function_context_from (context)
361 tree context ATTRIBUTE_UNUSED;
363 struct function *p = outer_function_chain;
364 struct var_refs_queue *queue;
366 cfun = p;
367 outer_function_chain = p->outer;
369 current_function_decl = p->decl;
370 reg_renumber = 0;
372 restore_emit_status (p);
374 (*lang_hooks.function.leave_nested) (p);
376 /* Finish doing put_var_into_stack for any of our variables which became
377 addressable during the nested function. If only one entry has to be
378 fixed up, just do that one. Otherwise, first make a list of MEMs that
379 are not to be unshared. */
380 if (p->fixup_var_refs_queue == 0)
382 else if (p->fixup_var_refs_queue->next == 0)
383 fixup_var_refs (p->fixup_var_refs_queue->modified,
384 p->fixup_var_refs_queue->promoted_mode,
385 p->fixup_var_refs_queue->unsignedp,
386 p->fixup_var_refs_queue->modified, 0);
387 else
389 rtx list = 0;
391 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
392 list = gen_rtx_EXPR_LIST (VOIDmode, queue->modified, list);
394 for (queue = p->fixup_var_refs_queue; queue; queue = queue->next)
395 fixup_var_refs (queue->modified, queue->promoted_mode,
396 queue->unsignedp, list, 0);
400 p->fixup_var_refs_queue = 0;
402 /* Reset variables that have known state during rtx generation. */
403 rtx_equal_function_value_matters = 1;
404 virtuals_instantiated = 0;
405 generating_concat_p = 1;
408 void
409 pop_function_context ()
411 pop_function_context_from (current_function_decl);
414 /* Clear out all parts of the state in F that can safely be discarded
415 after the function has been parsed, but not compiled, to let
416 garbage collection reclaim the memory. */
418 void
419 free_after_parsing (f)
420 struct function *f;
422 /* f->expr->forced_labels is used by code generation. */
423 /* f->emit->regno_reg_rtx is used by code generation. */
424 /* f->varasm is used by code generation. */
425 /* f->eh->eh_return_stub_label is used by code generation. */
427 (*lang_hooks.function.final) (f);
428 f->stmt = NULL;
431 /* Clear out all parts of the state in F that can safely be discarded
432 after the function has been compiled, to let garbage collection
433 reclaim the memory. */
435 void
436 free_after_compilation (f)
437 struct function *f;
439 f->eh = NULL;
440 f->expr = NULL;
441 f->emit = NULL;
442 f->varasm = NULL;
443 f->machine = NULL;
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_save_expr_regs = NULL;
456 f->x_stack_slot_list = NULL;
457 f->x_rtl_expr_chain = NULL;
458 f->x_tail_recursion_label = NULL;
459 f->x_tail_recursion_reentry = NULL;
460 f->x_arg_pointer_save_area = NULL;
461 f->x_clobber_return_insn = NULL;
462 f->x_context_display = NULL;
463 f->x_trampoline_list = NULL;
464 f->x_parm_birth_insn = NULL;
465 f->x_last_parm_insn = NULL;
466 f->x_parm_reg_stack_loc = NULL;
467 f->fixup_var_refs_queue = NULL;
468 f->original_arg_vector = NULL;
469 f->original_decl_initial = NULL;
470 f->inl_last_parm_insn = NULL;
471 f->epilogue_delay_list = NULL;
474 /* Allocate fixed slots in the stack frame of the current function. */
476 /* Return size needed for stack frame based on slots so far allocated in
477 function F.
478 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
479 the caller may have to do that. */
481 HOST_WIDE_INT
482 get_func_frame_size (f)
483 struct function *f;
485 #ifdef FRAME_GROWS_DOWNWARD
486 return -f->x_frame_offset;
487 #else
488 return f->x_frame_offset;
489 #endif
492 /* Return size needed for stack frame based on slots so far allocated.
493 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
494 the caller may have to do that. */
495 HOST_WIDE_INT
496 get_frame_size ()
498 return get_func_frame_size (cfun);
501 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
502 with machine mode MODE.
504 ALIGN controls the amount of alignment for the address of the slot:
505 0 means according to MODE,
506 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
507 positive specifies alignment boundary in bits.
509 We do not round to stack_boundary here.
511 FUNCTION specifies the function to allocate in. */
513 static rtx
514 assign_stack_local_1 (mode, size, align, function)
515 enum machine_mode mode;
516 HOST_WIDE_INT size;
517 int align;
518 struct function *function;
520 rtx x, addr;
521 int bigend_correction = 0;
522 int alignment;
523 int frame_off, frame_alignment, frame_phase;
525 if (align == 0)
527 tree type;
529 if (mode == BLKmode)
530 alignment = BIGGEST_ALIGNMENT;
531 else
532 alignment = GET_MODE_ALIGNMENT (mode);
534 /* Allow the target to (possibly) increase the alignment of this
535 stack slot. */
536 type = (*lang_hooks.types.type_for_mode) (mode, 0);
537 if (type)
538 alignment = LOCAL_ALIGNMENT (type, alignment);
540 alignment /= BITS_PER_UNIT;
542 else if (align == -1)
544 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
545 size = CEIL_ROUND (size, alignment);
547 else
548 alignment = align / BITS_PER_UNIT;
550 #ifdef FRAME_GROWS_DOWNWARD
551 function->x_frame_offset -= size;
552 #endif
554 /* Ignore alignment we can't do with expected alignment of the boundary. */
555 if (alignment * BITS_PER_UNIT > PREFERRED_STACK_BOUNDARY)
556 alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
558 if (function->stack_alignment_needed < alignment * BITS_PER_UNIT)
559 function->stack_alignment_needed = alignment * BITS_PER_UNIT;
561 /* Calculate how many bytes the start of local variables is off from
562 stack alignment. */
563 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
564 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
565 frame_phase = frame_off ? frame_alignment - frame_off : 0;
567 /* Round frame offset to that alignment.
568 We must be careful here, since FRAME_OFFSET might be negative and
569 division with a negative dividend isn't as well defined as we might
570 like. So we instead assume that ALIGNMENT is a power of two and
571 use logical operations which are unambiguous. */
572 #ifdef FRAME_GROWS_DOWNWARD
573 function->x_frame_offset = FLOOR_ROUND (function->x_frame_offset - frame_phase, alignment) + frame_phase;
574 #else
575 function->x_frame_offset = CEIL_ROUND (function->x_frame_offset - frame_phase, alignment) + frame_phase;
576 #endif
578 /* On a big-endian machine, if we are allocating more space than we will use,
579 use the least significant bytes of those that are allocated. */
580 if (BYTES_BIG_ENDIAN && mode != BLKmode)
581 bigend_correction = size - GET_MODE_SIZE (mode);
583 /* If we have already instantiated virtual registers, return the actual
584 address relative to the frame pointer. */
585 if (function == cfun && virtuals_instantiated)
586 addr = plus_constant (frame_pointer_rtx,
587 (frame_offset + bigend_correction
588 + STARTING_FRAME_OFFSET));
589 else
590 addr = plus_constant (virtual_stack_vars_rtx,
591 function->x_frame_offset + bigend_correction);
593 #ifndef FRAME_GROWS_DOWNWARD
594 function->x_frame_offset += size;
595 #endif
597 x = gen_rtx_MEM (mode, addr);
599 function->x_stack_slot_list
600 = gen_rtx_EXPR_LIST (VOIDmode, x, function->x_stack_slot_list);
602 return x;
605 /* Wrapper around assign_stack_local_1; assign a local stack slot for the
606 current function. */
609 assign_stack_local (mode, size, align)
610 enum machine_mode mode;
611 HOST_WIDE_INT size;
612 int align;
614 return assign_stack_local_1 (mode, size, align, cfun);
617 /* Allocate a temporary stack slot and record it for possible later
618 reuse.
620 MODE is the machine mode to be given to the returned rtx.
622 SIZE is the size in units of the space required. We do no rounding here
623 since assign_stack_local will do any required rounding.
625 KEEP is 1 if this slot is to be retained after a call to
626 free_temp_slots. Automatic variables for a block are allocated
627 with this flag. KEEP is 2 if we allocate a longer term temporary,
628 whose lifetime is controlled by CLEANUP_POINT_EXPRs. KEEP is 3
629 if we are to allocate something at an inner level to be treated as
630 a variable in the block (e.g., a SAVE_EXPR).
632 TYPE is the type that will be used for the stack slot. */
635 assign_stack_temp_for_type (mode, size, keep, type)
636 enum machine_mode mode;
637 HOST_WIDE_INT size;
638 int keep;
639 tree type;
641 unsigned int align;
642 struct temp_slot *p, *best_p = 0;
643 rtx slot;
645 /* If SIZE is -1 it means that somebody tried to allocate a temporary
646 of a variable size. */
647 if (size == -1)
648 abort ();
650 if (mode == BLKmode)
651 align = BIGGEST_ALIGNMENT;
652 else
653 align = GET_MODE_ALIGNMENT (mode);
655 if (! type)
656 type = (*lang_hooks.types.type_for_mode) (mode, 0);
658 if (type)
659 align = LOCAL_ALIGNMENT (type, align);
661 /* Try to find an available, already-allocated temporary of the proper
662 mode which meets the size and alignment requirements. Choose the
663 smallest one with the closest alignment. */
664 for (p = temp_slots; p; p = p->next)
665 if (p->align >= align && p->size >= size && GET_MODE (p->slot) == mode
666 && ! p->in_use
667 && objects_must_conflict_p (p->type, type)
668 && (best_p == 0 || best_p->size > p->size
669 || (best_p->size == p->size && best_p->align > p->align)))
671 if (p->align == align && p->size == size)
673 best_p = 0;
674 break;
676 best_p = p;
679 /* Make our best, if any, the one to use. */
680 if (best_p)
682 /* If there are enough aligned bytes left over, make them into a new
683 temp_slot so that the extra bytes don't get wasted. Do this only
684 for BLKmode slots, so that we can be sure of the alignment. */
685 if (GET_MODE (best_p->slot) == BLKmode)
687 int alignment = best_p->align / BITS_PER_UNIT;
688 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
690 if (best_p->size - rounded_size >= alignment)
692 p = (struct temp_slot *) ggc_alloc (sizeof (struct temp_slot));
693 p->in_use = p->addr_taken = 0;
694 p->size = best_p->size - rounded_size;
695 p->base_offset = best_p->base_offset + rounded_size;
696 p->full_size = best_p->full_size - rounded_size;
697 p->slot = gen_rtx_MEM (BLKmode,
698 plus_constant (XEXP (best_p->slot, 0),
699 rounded_size));
700 p->align = best_p->align;
701 p->address = 0;
702 p->rtl_expr = 0;
703 p->type = best_p->type;
704 p->next = temp_slots;
705 temp_slots = p;
707 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
708 stack_slot_list);
710 best_p->size = rounded_size;
711 best_p->full_size = rounded_size;
715 p = best_p;
718 /* If we still didn't find one, make a new temporary. */
719 if (p == 0)
721 HOST_WIDE_INT frame_offset_old = frame_offset;
723 p = (struct temp_slot *) ggc_alloc (sizeof (struct temp_slot));
725 /* We are passing an explicit alignment request to assign_stack_local.
726 One side effect of that is assign_stack_local will not round SIZE
727 to ensure the frame offset remains suitably aligned.
729 So for requests which depended on the rounding of SIZE, we go ahead
730 and round it now. We also make sure ALIGNMENT is at least
731 BIGGEST_ALIGNMENT. */
732 if (mode == BLKmode && align < BIGGEST_ALIGNMENT)
733 abort ();
734 p->slot = assign_stack_local (mode,
735 (mode == BLKmode
736 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
737 : size),
738 align);
740 p->align = align;
742 /* The following slot size computation is necessary because we don't
743 know the actual size of the temporary slot until assign_stack_local
744 has performed all the frame alignment and size rounding for the
745 requested temporary. Note that extra space added for alignment
746 can be either above or below this stack slot depending on which
747 way the frame grows. We include the extra space if and only if it
748 is above this slot. */
749 #ifdef FRAME_GROWS_DOWNWARD
750 p->size = frame_offset_old - frame_offset;
751 #else
752 p->size = size;
753 #endif
755 /* Now define the fields used by combine_temp_slots. */
756 #ifdef FRAME_GROWS_DOWNWARD
757 p->base_offset = frame_offset;
758 p->full_size = frame_offset_old - frame_offset;
759 #else
760 p->base_offset = frame_offset_old;
761 p->full_size = frame_offset - frame_offset_old;
762 #endif
763 p->address = 0;
764 p->next = temp_slots;
765 temp_slots = p;
768 p->in_use = 1;
769 p->addr_taken = 0;
770 p->rtl_expr = seq_rtl_expr;
771 p->type = type;
773 if (keep == 2)
775 p->level = target_temp_slot_level;
776 p->keep = 0;
778 else if (keep == 3)
780 p->level = var_temp_slot_level;
781 p->keep = 0;
783 else
785 p->level = temp_slot_level;
786 p->keep = keep;
790 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
791 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
792 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
794 /* If we know the alias set for the memory that will be used, use
795 it. If there's no TYPE, then we don't know anything about the
796 alias set for the memory. */
797 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
798 set_mem_align (slot, align);
800 /* If a type is specified, set the relevant flags. */
801 if (type != 0)
803 RTX_UNCHANGING_P (slot) = (lang_hooks.honor_readonly
804 && TYPE_READONLY (type));
805 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
806 MEM_SET_IN_STRUCT_P (slot, AGGREGATE_TYPE_P (type));
809 return slot;
812 /* Allocate a temporary stack slot and record it for possible later
813 reuse. First three arguments are same as in preceding function. */
816 assign_stack_temp (mode, size, keep)
817 enum machine_mode mode;
818 HOST_WIDE_INT size;
819 int keep;
821 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
824 /* Assign a temporary.
825 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
826 and so that should be used in error messages. In either case, we
827 allocate of the given type.
828 KEEP is as for assign_stack_temp.
829 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
830 it is 0 if a register is OK.
831 DONT_PROMOTE is 1 if we should not promote values in register
832 to wider modes. */
835 assign_temp (type_or_decl, keep, memory_required, dont_promote)
836 tree type_or_decl;
837 int keep;
838 int memory_required;
839 int dont_promote ATTRIBUTE_UNUSED;
841 tree type, decl;
842 enum machine_mode mode;
843 #ifndef PROMOTE_FOR_CALL_ONLY
844 int unsignedp;
845 #endif
847 if (DECL_P (type_or_decl))
848 decl = type_or_decl, type = TREE_TYPE (decl);
849 else
850 decl = NULL, type = type_or_decl;
852 mode = TYPE_MODE (type);
853 #ifndef PROMOTE_FOR_CALL_ONLY
854 unsignedp = TREE_UNSIGNED (type);
855 #endif
857 if (mode == BLKmode || memory_required)
859 HOST_WIDE_INT size = int_size_in_bytes (type);
860 rtx tmp;
862 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
863 problems with allocating the stack space. */
864 if (size == 0)
865 size = 1;
867 /* Unfortunately, we don't yet know how to allocate variable-sized
868 temporaries. However, sometimes we have a fixed upper limit on
869 the size (which is stored in TYPE_ARRAY_MAX_SIZE) and can use that
870 instead. This is the case for Chill variable-sized strings. */
871 if (size == -1 && TREE_CODE (type) == ARRAY_TYPE
872 && TYPE_ARRAY_MAX_SIZE (type) != NULL_TREE
873 && host_integerp (TYPE_ARRAY_MAX_SIZE (type), 1))
874 size = tree_low_cst (TYPE_ARRAY_MAX_SIZE (type), 1);
876 /* The size of the temporary may be too large to fit into an integer. */
877 /* ??? Not sure this should happen except for user silliness, so limit
878 this to things that aren't compiler-generated temporaries. The
879 rest of the time we'll abort in assign_stack_temp_for_type. */
880 if (decl && size == -1
881 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
883 error_with_decl (decl, "size of variable `%s' is too large");
884 size = 1;
887 tmp = assign_stack_temp_for_type (mode, size, keep, type);
888 return tmp;
891 #ifndef PROMOTE_FOR_CALL_ONLY
892 if (! dont_promote)
893 mode = promote_mode (type, mode, &unsignedp, 0);
894 #endif
896 return gen_reg_rtx (mode);
899 /* Combine temporary stack slots which are adjacent on the stack.
901 This allows for better use of already allocated stack space. This is only
902 done for BLKmode slots because we can be sure that we won't have alignment
903 problems in this case. */
905 void
906 combine_temp_slots ()
908 struct temp_slot *p, *q;
909 struct temp_slot *prev_p, *prev_q;
910 int num_slots;
912 /* We can't combine slots, because the information about which slot
913 is in which alias set will be lost. */
914 if (flag_strict_aliasing)
915 return;
917 /* If there are a lot of temp slots, don't do anything unless
918 high levels of optimization. */
919 if (! flag_expensive_optimizations)
920 for (p = temp_slots, num_slots = 0; p; p = p->next, num_slots++)
921 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
922 return;
924 for (p = temp_slots, prev_p = 0; p; p = prev_p ? prev_p->next : temp_slots)
926 int delete_p = 0;
928 if (! p->in_use && GET_MODE (p->slot) == BLKmode)
929 for (q = p->next, prev_q = p; q; q = prev_q->next)
931 int delete_q = 0;
932 if (! q->in_use && GET_MODE (q->slot) == BLKmode)
934 if (p->base_offset + p->full_size == q->base_offset)
936 /* Q comes after P; combine Q into P. */
937 p->size += q->size;
938 p->full_size += q->full_size;
939 delete_q = 1;
941 else if (q->base_offset + q->full_size == p->base_offset)
943 /* P comes after Q; combine P into Q. */
944 q->size += p->size;
945 q->full_size += p->full_size;
946 delete_p = 1;
947 break;
950 /* Either delete Q or advance past it. */
951 if (delete_q)
952 prev_q->next = q->next;
953 else
954 prev_q = q;
956 /* Either delete P or advance past it. */
957 if (delete_p)
959 if (prev_p)
960 prev_p->next = p->next;
961 else
962 temp_slots = p->next;
964 else
965 prev_p = p;
969 /* Find the temp slot corresponding to the object at address X. */
971 static struct temp_slot *
972 find_temp_slot_from_address (x)
973 rtx x;
975 struct temp_slot *p;
976 rtx next;
978 for (p = temp_slots; p; p = p->next)
980 if (! p->in_use)
981 continue;
983 else if (XEXP (p->slot, 0) == x
984 || p->address == 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))
990 return p;
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)
995 return p;
998 /* If we have a sum involving a register, see if it points to a temp
999 slot. */
1000 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == REG
1001 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
1002 return p;
1003 else if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == REG
1004 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
1005 return p;
1007 return 0;
1010 /* Indicate that NEW is an alternate way of referring to the temp slot
1011 that previously was known by OLD. */
1013 void
1014 update_temp_slot_address (old, new)
1015 rtx old, new;
1017 struct temp_slot *p;
1019 if (rtx_equal_p (old, new))
1020 return;
1022 p = find_temp_slot_from_address (old);
1024 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
1025 is a register, see if one operand of the PLUS is a temporary
1026 location. If so, NEW points into it. Otherwise, if both OLD and
1027 NEW are a PLUS and if there is a register in common between them.
1028 If so, try a recursive call on those values. */
1029 if (p == 0)
1031 if (GET_CODE (old) != PLUS)
1032 return;
1034 if (GET_CODE (new) == REG)
1036 update_temp_slot_address (XEXP (old, 0), new);
1037 update_temp_slot_address (XEXP (old, 1), new);
1038 return;
1040 else if (GET_CODE (new) != PLUS)
1041 return;
1043 if (rtx_equal_p (XEXP (old, 0), XEXP (new, 0)))
1044 update_temp_slot_address (XEXP (old, 1), XEXP (new, 1));
1045 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 0)))
1046 update_temp_slot_address (XEXP (old, 0), XEXP (new, 1));
1047 else if (rtx_equal_p (XEXP (old, 0), XEXP (new, 1)))
1048 update_temp_slot_address (XEXP (old, 1), XEXP (new, 0));
1049 else if (rtx_equal_p (XEXP (old, 1), XEXP (new, 1)))
1050 update_temp_slot_address (XEXP (old, 0), XEXP (new, 0));
1052 return;
1055 /* Otherwise add an alias for the temp's address. */
1056 else if (p->address == 0)
1057 p->address = new;
1058 else
1060 if (GET_CODE (p->address) != EXPR_LIST)
1061 p->address = gen_rtx_EXPR_LIST (VOIDmode, p->address, NULL_RTX);
1063 p->address = gen_rtx_EXPR_LIST (VOIDmode, new, p->address);
1067 /* If X could be a reference to a temporary slot, mark the fact that its
1068 address was taken. */
1070 void
1071 mark_temp_addr_taken (x)
1072 rtx x;
1074 struct temp_slot *p;
1076 if (x == 0)
1077 return;
1079 /* If X is not in memory or is at a constant address, it cannot be in
1080 a temporary slot. */
1081 if (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1082 return;
1084 p = find_temp_slot_from_address (XEXP (x, 0));
1085 if (p != 0)
1086 p->addr_taken = 1;
1089 /* If X could be a reference to a temporary slot, mark that slot as
1090 belonging to the to one level higher than the current level. If X
1091 matched one of our slots, just mark that one. Otherwise, we can't
1092 easily predict which it is, so upgrade all of them. Kept slots
1093 need not be touched.
1095 This is called when an ({...}) construct occurs and a statement
1096 returns a value in memory. */
1098 void
1099 preserve_temp_slots (x)
1100 rtx x;
1102 struct temp_slot *p = 0;
1104 /* If there is no result, we still might have some objects whose address
1105 were taken, so we need to make sure they stay around. */
1106 if (x == 0)
1108 for (p = temp_slots; p; p = p->next)
1109 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1110 p->level--;
1112 return;
1115 /* If X is a register that is being used as a pointer, see if we have
1116 a temporary slot we know it points to. To be consistent with
1117 the code below, we really should preserve all non-kept slots
1118 if we can't find a match, but that seems to be much too costly. */
1119 if (GET_CODE (x) == REG && REG_POINTER (x))
1120 p = find_temp_slot_from_address (x);
1122 /* If X is not in memory or is at a constant address, it cannot be in
1123 a temporary slot, but it can contain something whose address was
1124 taken. */
1125 if (p == 0 && (GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0))))
1127 for (p = temp_slots; p; p = p->next)
1128 if (p->in_use && p->level == temp_slot_level && p->addr_taken)
1129 p->level--;
1131 return;
1134 /* First see if we can find a match. */
1135 if (p == 0)
1136 p = find_temp_slot_from_address (XEXP (x, 0));
1138 if (p != 0)
1140 /* Move everything at our level whose address was taken to our new
1141 level in case we used its address. */
1142 struct temp_slot *q;
1144 if (p->level == temp_slot_level)
1146 for (q = temp_slots; q; q = q->next)
1147 if (q != p && q->addr_taken && q->level == p->level)
1148 q->level--;
1150 p->level--;
1151 p->addr_taken = 0;
1153 return;
1156 /* Otherwise, preserve all non-kept slots at this level. */
1157 for (p = temp_slots; p; p = p->next)
1158 if (p->in_use && p->level == temp_slot_level && ! p->keep)
1159 p->level--;
1162 /* X is the result of an RTL_EXPR. If it is a temporary slot associated
1163 with that RTL_EXPR, promote it into a temporary slot at the present
1164 level so it will not be freed when we free slots made in the
1165 RTL_EXPR. */
1167 void
1168 preserve_rtl_expr_result (x)
1169 rtx x;
1171 struct temp_slot *p;
1173 /* If X is not in memory or is at a constant address, it cannot be in
1174 a temporary slot. */
1175 if (x == 0 || GET_CODE (x) != MEM || CONSTANT_P (XEXP (x, 0)))
1176 return;
1178 /* If we can find a match, move it to our level unless it is already at
1179 an upper level. */
1180 p = find_temp_slot_from_address (XEXP (x, 0));
1181 if (p != 0)
1183 p->level = MIN (p->level, temp_slot_level);
1184 p->rtl_expr = 0;
1187 return;
1190 /* Free all temporaries used so far. This is normally called at the end
1191 of generating code for a statement. Don't free any temporaries
1192 currently in use for an RTL_EXPR that hasn't yet been emitted.
1193 We could eventually do better than this since it can be reused while
1194 generating the same RTL_EXPR, but this is complex and probably not
1195 worthwhile. */
1197 void
1198 free_temp_slots ()
1200 struct temp_slot *p;
1202 for (p = temp_slots; p; p = p->next)
1203 if (p->in_use && p->level == temp_slot_level && ! p->keep
1204 && p->rtl_expr == 0)
1205 p->in_use = 0;
1207 combine_temp_slots ();
1210 /* Free all temporary slots used in T, an RTL_EXPR node. */
1212 void
1213 free_temps_for_rtl_expr (t)
1214 tree t;
1216 struct temp_slot *p;
1218 for (p = temp_slots; p; p = p->next)
1219 if (p->rtl_expr == t)
1221 /* If this slot is below the current TEMP_SLOT_LEVEL, then it
1222 needs to be preserved. This can happen if a temporary in
1223 the RTL_EXPR was addressed; preserve_temp_slots will move
1224 the temporary into a higher level. */
1225 if (temp_slot_level <= p->level)
1226 p->in_use = 0;
1227 else
1228 p->rtl_expr = NULL_TREE;
1231 combine_temp_slots ();
1234 /* Mark all temporaries ever allocated in this function as not suitable
1235 for reuse until the current level is exited. */
1237 void
1238 mark_all_temps_used ()
1240 struct temp_slot *p;
1242 for (p = temp_slots; p; p = p->next)
1244 p->in_use = p->keep = 1;
1245 p->level = MIN (p->level, temp_slot_level);
1249 /* Push deeper into the nesting level for stack temporaries. */
1251 void
1252 push_temp_slots ()
1254 temp_slot_level++;
1257 /* Pop a temporary nesting level. All slots in use in the current level
1258 are freed. */
1260 void
1261 pop_temp_slots ()
1263 struct temp_slot *p;
1265 for (p = temp_slots; p; p = p->next)
1266 if (p->in_use && p->level == temp_slot_level && p->rtl_expr == 0)
1267 p->in_use = 0;
1269 combine_temp_slots ();
1271 temp_slot_level--;
1274 /* Initialize temporary slots. */
1276 void
1277 init_temp_slots ()
1279 /* We have not allocated any temporaries yet. */
1280 temp_slots = 0;
1281 temp_slot_level = 0;
1282 var_temp_slot_level = 0;
1283 target_temp_slot_level = 0;
1286 /* Retroactively move an auto variable from a register to a stack slot.
1287 This is done when an address-reference to the variable is seen. */
1289 void
1290 put_var_into_stack (decl)
1291 tree decl;
1293 rtx reg;
1294 enum machine_mode promoted_mode, decl_mode;
1295 struct function *function = 0;
1296 tree context;
1297 int can_use_addressof;
1298 int volatilep = TREE_CODE (decl) != SAVE_EXPR && TREE_THIS_VOLATILE (decl);
1299 int usedp = (TREE_USED (decl)
1300 || (TREE_CODE (decl) != SAVE_EXPR && DECL_INITIAL (decl) != 0));
1302 context = decl_function_context (decl);
1304 /* Get the current rtl used for this object and its original mode. */
1305 reg = (TREE_CODE (decl) == SAVE_EXPR
1306 ? SAVE_EXPR_RTL (decl)
1307 : DECL_RTL_IF_SET (decl));
1309 /* No need to do anything if decl has no rtx yet
1310 since in that case caller is setting TREE_ADDRESSABLE
1311 and a stack slot will be assigned when the rtl is made. */
1312 if (reg == 0)
1313 return;
1315 /* Get the declared mode for this object. */
1316 decl_mode = (TREE_CODE (decl) == SAVE_EXPR ? TYPE_MODE (TREE_TYPE (decl))
1317 : DECL_MODE (decl));
1318 /* Get the mode it's actually stored in. */
1319 promoted_mode = GET_MODE (reg);
1321 /* If this variable comes from an outer function, find that
1322 function's saved context. Don't use find_function_data here,
1323 because it might not be in any active function.
1324 FIXME: Is that really supposed to happen?
1325 It does in ObjC at least. */
1326 if (context != current_function_decl && context != inline_function_decl)
1327 for (function = outer_function_chain; function; function = function->outer)
1328 if (function->decl == context)
1329 break;
1331 /* If this is a variable-size object with a pseudo to address it,
1332 put that pseudo into the stack, if the var is nonlocal. */
1333 if (TREE_CODE (decl) != SAVE_EXPR && DECL_NONLOCAL (decl)
1334 && GET_CODE (reg) == MEM
1335 && GET_CODE (XEXP (reg, 0)) == REG
1336 && REGNO (XEXP (reg, 0)) > LAST_VIRTUAL_REGISTER)
1338 reg = XEXP (reg, 0);
1339 decl_mode = promoted_mode = GET_MODE (reg);
1342 can_use_addressof
1343 = (function == 0
1344 && optimize > 0
1345 /* FIXME make it work for promoted modes too */
1346 && decl_mode == promoted_mode
1347 #ifdef NON_SAVING_SETJMP
1348 && ! (NON_SAVING_SETJMP && current_function_calls_setjmp)
1349 #endif
1352 /* If we can't use ADDRESSOF, make sure we see through one we already
1353 generated. */
1354 if (! can_use_addressof && GET_CODE (reg) == MEM
1355 && GET_CODE (XEXP (reg, 0)) == ADDRESSOF)
1356 reg = XEXP (XEXP (reg, 0), 0);
1358 /* Now we should have a value that resides in one or more pseudo regs. */
1360 if (GET_CODE (reg) == REG)
1362 /* If this variable lives in the current function and we don't need
1363 to put things in the stack for the sake of setjmp, try to keep it
1364 in a register until we know we actually need the address. */
1365 if (can_use_addressof)
1366 gen_mem_addressof (reg, decl);
1367 else
1368 put_reg_into_stack (function, reg, TREE_TYPE (decl), promoted_mode,
1369 decl_mode, volatilep, 0, usedp, 0);
1371 else if (GET_CODE (reg) == CONCAT)
1373 /* A CONCAT contains two pseudos; put them both in the stack.
1374 We do it so they end up consecutive.
1375 We fixup references to the parts only after we fixup references
1376 to the whole CONCAT, lest we do double fixups for the latter
1377 references. */
1378 enum machine_mode part_mode = GET_MODE (XEXP (reg, 0));
1379 tree part_type = (*lang_hooks.types.type_for_mode) (part_mode, 0);
1380 rtx lopart = XEXP (reg, 0);
1381 rtx hipart = XEXP (reg, 1);
1382 #ifdef FRAME_GROWS_DOWNWARD
1383 /* Since part 0 should have a lower address, do it second. */
1384 put_reg_into_stack (function, hipart, part_type, part_mode,
1385 part_mode, volatilep, 0, 0, 0);
1386 put_reg_into_stack (function, lopart, part_type, part_mode,
1387 part_mode, volatilep, 0, 0, 0);
1388 #else
1389 put_reg_into_stack (function, lopart, part_type, part_mode,
1390 part_mode, volatilep, 0, 0, 0);
1391 put_reg_into_stack (function, hipart, part_type, part_mode,
1392 part_mode, volatilep, 0, 0, 0);
1393 #endif
1395 /* Change the CONCAT into a combined MEM for both parts. */
1396 PUT_CODE (reg, MEM);
1397 MEM_ATTRS (reg) = 0;
1399 /* set_mem_attributes uses DECL_RTL to avoid re-generating of
1400 already computed alias sets. Here we want to re-generate. */
1401 if (DECL_P (decl))
1402 SET_DECL_RTL (decl, NULL);
1403 set_mem_attributes (reg, decl, 1);
1404 if (DECL_P (decl))
1405 SET_DECL_RTL (decl, reg);
1407 /* The two parts are in memory order already.
1408 Use the lower parts address as ours. */
1409 XEXP (reg, 0) = XEXP (XEXP (reg, 0), 0);
1410 /* Prevent sharing of rtl that might lose. */
1411 if (GET_CODE (XEXP (reg, 0)) == PLUS)
1412 XEXP (reg, 0) = copy_rtx (XEXP (reg, 0));
1413 if (usedp)
1415 schedule_fixup_var_refs (function, reg, TREE_TYPE (decl),
1416 promoted_mode, 0);
1417 schedule_fixup_var_refs (function, lopart, part_type, part_mode, 0);
1418 schedule_fixup_var_refs (function, hipart, part_type, part_mode, 0);
1421 else
1422 return;
1425 /* Subroutine of put_var_into_stack. This puts a single pseudo reg REG
1426 into the stack frame of FUNCTION (0 means the current function).
1427 DECL_MODE is the machine mode of the user-level data type.
1428 PROMOTED_MODE is the machine mode of the register.
1429 VOLATILE_P is nonzero if this is for a "volatile" decl.
1430 USED_P is nonzero if this reg might have already been used in an insn. */
1432 static void
1433 put_reg_into_stack (function, reg, type, promoted_mode, decl_mode, volatile_p,
1434 original_regno, used_p, ht)
1435 struct function *function;
1436 rtx reg;
1437 tree type;
1438 enum machine_mode promoted_mode, decl_mode;
1439 int volatile_p;
1440 unsigned int original_regno;
1441 int used_p;
1442 htab_t ht;
1444 struct function *func = function ? function : cfun;
1445 rtx new = 0;
1446 unsigned int regno = original_regno;
1448 if (regno == 0)
1449 regno = REGNO (reg);
1451 if (regno < func->x_max_parm_reg)
1452 new = func->x_parm_reg_stack_loc[regno];
1454 if (new == 0)
1455 new = assign_stack_local_1 (decl_mode, GET_MODE_SIZE (decl_mode), 0, func);
1457 PUT_CODE (reg, MEM);
1458 PUT_MODE (reg, decl_mode);
1459 XEXP (reg, 0) = XEXP (new, 0);
1460 MEM_ATTRS (reg) = 0;
1461 /* `volatil' bit means one thing for MEMs, another entirely for REGs. */
1462 MEM_VOLATILE_P (reg) = volatile_p;
1464 /* If this is a memory ref that contains aggregate components,
1465 mark it as such for cse and loop optimize. If we are reusing a
1466 previously generated stack slot, then we need to copy the bit in
1467 case it was set for other reasons. For instance, it is set for
1468 __builtin_va_alist. */
1469 if (type)
1471 MEM_SET_IN_STRUCT_P (reg,
1472 AGGREGATE_TYPE_P (type) || MEM_IN_STRUCT_P (new));
1473 set_mem_alias_set (reg, get_alias_set (type));
1476 if (used_p)
1477 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht);
1480 /* Make sure that all refs to the variable, previously made
1481 when it was a register, are fixed up to be valid again.
1482 See function above for meaning of arguments. */
1484 static void
1485 schedule_fixup_var_refs (function, reg, type, promoted_mode, ht)
1486 struct function *function;
1487 rtx reg;
1488 tree type;
1489 enum machine_mode promoted_mode;
1490 htab_t ht;
1492 int unsigned_p = type ? TREE_UNSIGNED (type) : 0;
1494 if (function != 0)
1496 struct var_refs_queue *temp;
1498 temp
1499 = (struct var_refs_queue *) ggc_alloc (sizeof (struct var_refs_queue));
1500 temp->modified = reg;
1501 temp->promoted_mode = promoted_mode;
1502 temp->unsignedp = unsigned_p;
1503 temp->next = function->fixup_var_refs_queue;
1504 function->fixup_var_refs_queue = temp;
1506 else
1507 /* Variable is local; fix it up now. */
1508 fixup_var_refs (reg, promoted_mode, unsigned_p, reg, ht);
1511 static void
1512 fixup_var_refs (var, promoted_mode, unsignedp, may_share, ht)
1513 rtx var;
1514 enum machine_mode promoted_mode;
1515 int unsignedp;
1516 htab_t ht;
1517 rtx may_share;
1519 tree pending;
1520 rtx first_insn = get_insns ();
1521 struct sequence_stack *stack = seq_stack;
1522 tree rtl_exps = rtl_expr_chain;
1524 /* If there's a hash table, it must record all uses of VAR. */
1525 if (ht)
1527 if (stack != 0)
1528 abort ();
1529 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp,
1530 may_share);
1531 return;
1534 fixup_var_refs_insns (first_insn, var, promoted_mode, unsignedp,
1535 stack == 0, may_share);
1537 /* Scan all pending sequences too. */
1538 for (; stack; stack = stack->next)
1540 push_to_full_sequence (stack->first, stack->last);
1541 fixup_var_refs_insns (stack->first, var, promoted_mode, unsignedp,
1542 stack->next != 0, may_share);
1543 /* Update remembered end of sequence
1544 in case we added an insn at the end. */
1545 stack->last = get_last_insn ();
1546 end_sequence ();
1549 /* Scan all waiting RTL_EXPRs too. */
1550 for (pending = rtl_exps; pending; pending = TREE_CHAIN (pending))
1552 rtx seq = RTL_EXPR_SEQUENCE (TREE_VALUE (pending));
1553 if (seq != const0_rtx && seq != 0)
1555 push_to_sequence (seq);
1556 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1557 may_share);
1558 end_sequence ();
1563 /* REPLACEMENTS is a pointer to a list of the struct fixup_replacement and X is
1564 some part of an insn. Return a struct fixup_replacement whose OLD
1565 value is equal to X. Allocate a new structure if no such entry exists. */
1567 static struct fixup_replacement *
1568 find_fixup_replacement (replacements, x)
1569 struct fixup_replacement **replacements;
1570 rtx x;
1572 struct fixup_replacement *p;
1574 /* See if we have already replaced this. */
1575 for (p = *replacements; p != 0 && ! rtx_equal_p (p->old, x); p = p->next)
1578 if (p == 0)
1580 p = (struct fixup_replacement *) xmalloc (sizeof (struct fixup_replacement));
1581 p->old = x;
1582 p->new = 0;
1583 p->next = *replacements;
1584 *replacements = p;
1587 return p;
1590 /* Scan the insn-chain starting with INSN for refs to VAR and fix them
1591 up. TOPLEVEL is nonzero if this chain is the main chain of insns
1592 for the current function. MAY_SHARE is either a MEM that is not
1593 to be unshared or a list of them. */
1595 static void
1596 fixup_var_refs_insns (insn, var, promoted_mode, unsignedp, toplevel, may_share)
1597 rtx insn;
1598 rtx var;
1599 enum machine_mode promoted_mode;
1600 int unsignedp;
1601 int toplevel;
1602 rtx may_share;
1604 while (insn)
1606 /* fixup_var_refs_insn might modify insn, so save its next
1607 pointer now. */
1608 rtx next = NEXT_INSN (insn);
1610 /* CALL_PLACEHOLDERs are special; we have to switch into each of
1611 the three sequences they (potentially) contain, and process
1612 them recursively. The CALL_INSN itself is not interesting. */
1614 if (GET_CODE (insn) == CALL_INSN
1615 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
1617 int i;
1619 /* Look at the Normal call, sibling call and tail recursion
1620 sequences attached to the CALL_PLACEHOLDER. */
1621 for (i = 0; i < 3; i++)
1623 rtx seq = XEXP (PATTERN (insn), i);
1624 if (seq)
1626 push_to_sequence (seq);
1627 fixup_var_refs_insns (seq, var, promoted_mode, unsignedp, 0,
1628 may_share);
1629 XEXP (PATTERN (insn), i) = get_insns ();
1630 end_sequence ();
1635 else if (INSN_P (insn))
1636 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel,
1637 may_share);
1639 insn = next;
1643 /* Look up the insns which reference VAR in HT and fix them up. Other
1644 arguments are the same as fixup_var_refs_insns.
1646 N.B. No need for special processing of CALL_PLACEHOLDERs here,
1647 because the hash table will point straight to the interesting insn
1648 (inside the CALL_PLACEHOLDER). */
1650 static void
1651 fixup_var_refs_insns_with_hash (ht, var, promoted_mode, unsignedp, may_share)
1652 htab_t ht;
1653 rtx var;
1654 enum machine_mode promoted_mode;
1655 int unsignedp;
1656 rtx may_share;
1658 struct insns_for_mem_entry tmp;
1659 struct insns_for_mem_entry *ime;
1660 rtx insn_list;
1662 tmp.key = var;
1663 ime = (struct insns_for_mem_entry *) htab_find (ht, &tmp);
1664 for (insn_list = ime->insns; insn_list != 0; insn_list = XEXP (insn_list, 1))
1665 if (INSN_P (XEXP (insn_list, 0)))
1666 fixup_var_refs_insn (XEXP (insn_list, 0), var, promoted_mode,
1667 unsignedp, 1, may_share);
1671 /* Per-insn processing by fixup_var_refs_insns(_with_hash). INSN is
1672 the insn under examination, VAR is the variable to fix up
1673 references to, PROMOTED_MODE and UNSIGNEDP describe VAR, and
1674 TOPLEVEL is nonzero if this is the main insn chain for this
1675 function. */
1677 static void
1678 fixup_var_refs_insn (insn, var, promoted_mode, unsignedp, toplevel, no_share)
1679 rtx insn;
1680 rtx var;
1681 enum machine_mode promoted_mode;
1682 int unsignedp;
1683 int toplevel;
1684 rtx no_share;
1686 rtx call_dest = 0;
1687 rtx set, prev, prev_set;
1688 rtx note;
1690 /* Remember the notes in case we delete the insn. */
1691 note = REG_NOTES (insn);
1693 /* If this is a CLOBBER of VAR, delete it.
1695 If it has a REG_LIBCALL note, delete the REG_LIBCALL
1696 and REG_RETVAL notes too. */
1697 if (GET_CODE (PATTERN (insn)) == CLOBBER
1698 && (XEXP (PATTERN (insn), 0) == var
1699 || (GET_CODE (XEXP (PATTERN (insn), 0)) == CONCAT
1700 && (XEXP (XEXP (PATTERN (insn), 0), 0) == var
1701 || XEXP (XEXP (PATTERN (insn), 0), 1) == var))))
1703 if ((note = find_reg_note (insn, REG_LIBCALL, NULL_RTX)) != 0)
1704 /* The REG_LIBCALL note will go away since we are going to
1705 turn INSN into a NOTE, so just delete the
1706 corresponding REG_RETVAL note. */
1707 remove_note (XEXP (note, 0),
1708 find_reg_note (XEXP (note, 0), REG_RETVAL,
1709 NULL_RTX));
1711 delete_insn (insn);
1714 /* The insn to load VAR from a home in the arglist
1715 is now a no-op. When we see it, just delete it.
1716 Similarly if this is storing VAR from a register from which
1717 it was loaded in the previous insn. This will occur
1718 when an ADDRESSOF was made for an arglist slot. */
1719 else if (toplevel
1720 && (set = single_set (insn)) != 0
1721 && SET_DEST (set) == var
1722 /* If this represents the result of an insn group,
1723 don't delete the insn. */
1724 && find_reg_note (insn, REG_RETVAL, NULL_RTX) == 0
1725 && (rtx_equal_p (SET_SRC (set), var)
1726 || (GET_CODE (SET_SRC (set)) == REG
1727 && (prev = prev_nonnote_insn (insn)) != 0
1728 && (prev_set = single_set (prev)) != 0
1729 && SET_DEST (prev_set) == SET_SRC (set)
1730 && rtx_equal_p (SET_SRC (prev_set), var))))
1732 delete_insn (insn);
1734 else
1736 struct fixup_replacement *replacements = 0;
1737 rtx next_insn = NEXT_INSN (insn);
1739 if (SMALL_REGISTER_CLASSES)
1741 /* If the insn that copies the results of a CALL_INSN
1742 into a pseudo now references VAR, we have to use an
1743 intermediate pseudo since we want the life of the
1744 return value register to be only a single insn.
1746 If we don't use an intermediate pseudo, such things as
1747 address computations to make the address of VAR valid
1748 if it is not can be placed between the CALL_INSN and INSN.
1750 To make sure this doesn't happen, we record the destination
1751 of the CALL_INSN and see if the next insn uses both that
1752 and VAR. */
1754 if (call_dest != 0 && GET_CODE (insn) == INSN
1755 && reg_mentioned_p (var, PATTERN (insn))
1756 && reg_mentioned_p (call_dest, PATTERN (insn)))
1758 rtx temp = gen_reg_rtx (GET_MODE (call_dest));
1760 emit_insn_before (gen_move_insn (temp, call_dest), insn);
1762 PATTERN (insn) = replace_rtx (PATTERN (insn),
1763 call_dest, temp);
1766 if (GET_CODE (insn) == CALL_INSN
1767 && GET_CODE (PATTERN (insn)) == SET)
1768 call_dest = SET_DEST (PATTERN (insn));
1769 else if (GET_CODE (insn) == CALL_INSN
1770 && GET_CODE (PATTERN (insn)) == PARALLEL
1771 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == SET)
1772 call_dest = SET_DEST (XVECEXP (PATTERN (insn), 0, 0));
1773 else
1774 call_dest = 0;
1777 /* See if we have to do anything to INSN now that VAR is in
1778 memory. If it needs to be loaded into a pseudo, use a single
1779 pseudo for the entire insn in case there is a MATCH_DUP
1780 between two operands. We pass a pointer to the head of
1781 a list of struct fixup_replacements. If fixup_var_refs_1
1782 needs to allocate pseudos or replacement MEMs (for SUBREGs),
1783 it will record them in this list.
1785 If it allocated a pseudo for any replacement, we copy into
1786 it here. */
1788 fixup_var_refs_1 (var, promoted_mode, &PATTERN (insn), insn,
1789 &replacements, no_share);
1791 /* If this is last_parm_insn, and any instructions were output
1792 after it to fix it up, then we must set last_parm_insn to
1793 the last such instruction emitted. */
1794 if (insn == last_parm_insn)
1795 last_parm_insn = PREV_INSN (next_insn);
1797 while (replacements)
1799 struct fixup_replacement *next;
1801 if (GET_CODE (replacements->new) == REG)
1803 rtx insert_before;
1804 rtx seq;
1806 /* OLD might be a (subreg (mem)). */
1807 if (GET_CODE (replacements->old) == SUBREG)
1808 replacements->old
1809 = fixup_memory_subreg (replacements->old, insn,
1810 promoted_mode, 0);
1811 else
1812 replacements->old
1813 = fixup_stack_1 (replacements->old, insn);
1815 insert_before = insn;
1817 /* If we are changing the mode, do a conversion.
1818 This might be wasteful, but combine.c will
1819 eliminate much of the waste. */
1821 if (GET_MODE (replacements->new)
1822 != GET_MODE (replacements->old))
1824 start_sequence ();
1825 convert_move (replacements->new,
1826 replacements->old, unsignedp);
1827 seq = get_insns ();
1828 end_sequence ();
1830 else
1831 seq = gen_move_insn (replacements->new,
1832 replacements->old);
1834 emit_insn_before (seq, insert_before);
1837 next = replacements->next;
1838 free (replacements);
1839 replacements = next;
1843 /* Also fix up any invalid exprs in the REG_NOTES of this insn.
1844 But don't touch other insns referred to by reg-notes;
1845 we will get them elsewhere. */
1846 while (note)
1848 if (GET_CODE (note) != INSN_LIST)
1849 XEXP (note, 0)
1850 = walk_fixup_memory_subreg (XEXP (note, 0), insn,
1851 promoted_mode, 1);
1852 note = XEXP (note, 1);
1856 /* VAR is a MEM that used to be a pseudo register with mode PROMOTED_MODE.
1857 See if the rtx expression at *LOC in INSN needs to be changed.
1859 REPLACEMENTS is a pointer to a list head that starts out zero, but may
1860 contain a list of original rtx's and replacements. If we find that we need
1861 to modify this insn by replacing a memory reference with a pseudo or by
1862 making a new MEM to implement a SUBREG, we consult that list to see if
1863 we have already chosen a replacement. If none has already been allocated,
1864 we allocate it and update the list. fixup_var_refs_insn will copy VAR
1865 or the SUBREG, as appropriate, to the pseudo. */
1867 static void
1868 fixup_var_refs_1 (var, promoted_mode, loc, insn, replacements, no_share)
1869 rtx var;
1870 enum machine_mode promoted_mode;
1871 rtx *loc;
1872 rtx insn;
1873 struct fixup_replacement **replacements;
1874 rtx no_share;
1876 int i;
1877 rtx x = *loc;
1878 RTX_CODE code = GET_CODE (x);
1879 const char *fmt;
1880 rtx tem, tem1;
1881 struct fixup_replacement *replacement;
1883 switch (code)
1885 case ADDRESSOF:
1886 if (XEXP (x, 0) == var)
1888 /* Prevent sharing of rtl that might lose. */
1889 rtx sub = copy_rtx (XEXP (var, 0));
1891 if (! validate_change (insn, loc, sub, 0))
1893 rtx y = gen_reg_rtx (GET_MODE (sub));
1894 rtx seq, new_insn;
1896 /* We should be able to replace with a register or all is lost.
1897 Note that we can't use validate_change to verify this, since
1898 we're not caring for replacing all dups simultaneously. */
1899 if (! validate_replace_rtx (*loc, y, insn))
1900 abort ();
1902 /* Careful! First try to recognize a direct move of the
1903 value, mimicking how things are done in gen_reload wrt
1904 PLUS. Consider what happens when insn is a conditional
1905 move instruction and addsi3 clobbers flags. */
1907 start_sequence ();
1908 new_insn = emit_insn (gen_rtx_SET (VOIDmode, y, sub));
1909 seq = get_insns ();
1910 end_sequence ();
1912 if (recog_memoized (new_insn) < 0)
1914 /* That failed. Fall back on force_operand and hope. */
1916 start_sequence ();
1917 sub = force_operand (sub, y);
1918 if (sub != y)
1919 emit_insn (gen_move_insn (y, sub));
1920 seq = get_insns ();
1921 end_sequence ();
1924 #ifdef HAVE_cc0
1925 /* Don't separate setter from user. */
1926 if (PREV_INSN (insn) && sets_cc0_p (PREV_INSN (insn)))
1927 insn = PREV_INSN (insn);
1928 #endif
1930 emit_insn_before (seq, insn);
1933 return;
1935 case MEM:
1936 if (var == x)
1938 /* If we already have a replacement, use it. Otherwise,
1939 try to fix up this address in case it is invalid. */
1941 replacement = find_fixup_replacement (replacements, var);
1942 if (replacement->new)
1944 *loc = replacement->new;
1945 return;
1948 *loc = replacement->new = x = fixup_stack_1 (x, insn);
1950 /* Unless we are forcing memory to register or we changed the mode,
1951 we can leave things the way they are if the insn is valid. */
1953 INSN_CODE (insn) = -1;
1954 if (! flag_force_mem && GET_MODE (x) == promoted_mode
1955 && recog_memoized (insn) >= 0)
1956 return;
1958 *loc = replacement->new = gen_reg_rtx (promoted_mode);
1959 return;
1962 /* If X contains VAR, we need to unshare it here so that we update
1963 each occurrence separately. But all identical MEMs in one insn
1964 must be replaced with the same rtx because of the possibility of
1965 MATCH_DUPs. */
1967 if (reg_mentioned_p (var, x))
1969 replacement = find_fixup_replacement (replacements, x);
1970 if (replacement->new == 0)
1971 replacement->new = copy_most_rtx (x, no_share);
1973 *loc = x = replacement->new;
1974 code = GET_CODE (x);
1976 break;
1978 case REG:
1979 case CC0:
1980 case PC:
1981 case CONST_INT:
1982 case CONST:
1983 case SYMBOL_REF:
1984 case LABEL_REF:
1985 case CONST_DOUBLE:
1986 case CONST_VECTOR:
1987 return;
1989 case SIGN_EXTRACT:
1990 case ZERO_EXTRACT:
1991 /* Note that in some cases those types of expressions are altered
1992 by optimize_bit_field, and do not survive to get here. */
1993 if (XEXP (x, 0) == var
1994 || (GET_CODE (XEXP (x, 0)) == SUBREG
1995 && SUBREG_REG (XEXP (x, 0)) == var))
1997 /* Get TEM as a valid MEM in the mode presently in the insn.
1999 We don't worry about the possibility of MATCH_DUP here; it
2000 is highly unlikely and would be tricky to handle. */
2002 tem = XEXP (x, 0);
2003 if (GET_CODE (tem) == SUBREG)
2005 if (GET_MODE_BITSIZE (GET_MODE (tem))
2006 > GET_MODE_BITSIZE (GET_MODE (var)))
2008 replacement = find_fixup_replacement (replacements, var);
2009 if (replacement->new == 0)
2010 replacement->new = gen_reg_rtx (GET_MODE (var));
2011 SUBREG_REG (tem) = replacement->new;
2013 /* The following code works only if we have a MEM, so we
2014 need to handle the subreg here. We directly substitute
2015 it assuming that a subreg must be OK here. We already
2016 scheduled a replacement to copy the mem into the
2017 subreg. */
2018 XEXP (x, 0) = tem;
2019 return;
2021 else
2022 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2024 else
2025 tem = fixup_stack_1 (tem, insn);
2027 /* Unless we want to load from memory, get TEM into the proper mode
2028 for an extract from memory. This can only be done if the
2029 extract is at a constant position and length. */
2031 if (! flag_force_mem && GET_CODE (XEXP (x, 1)) == CONST_INT
2032 && GET_CODE (XEXP (x, 2)) == CONST_INT
2033 && ! mode_dependent_address_p (XEXP (tem, 0))
2034 && ! MEM_VOLATILE_P (tem))
2036 enum machine_mode wanted_mode = VOIDmode;
2037 enum machine_mode is_mode = GET_MODE (tem);
2038 HOST_WIDE_INT pos = INTVAL (XEXP (x, 2));
2040 if (GET_CODE (x) == ZERO_EXTRACT)
2042 enum machine_mode new_mode
2043 = mode_for_extraction (EP_extzv, 1);
2044 if (new_mode != MAX_MACHINE_MODE)
2045 wanted_mode = new_mode;
2047 else if (GET_CODE (x) == SIGN_EXTRACT)
2049 enum machine_mode new_mode
2050 = mode_for_extraction (EP_extv, 1);
2051 if (new_mode != MAX_MACHINE_MODE)
2052 wanted_mode = new_mode;
2055 /* If we have a narrower mode, we can do something. */
2056 if (wanted_mode != VOIDmode
2057 && GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2059 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2060 rtx old_pos = XEXP (x, 2);
2061 rtx newmem;
2063 /* If the bytes and bits are counted differently, we
2064 must adjust the offset. */
2065 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2066 offset = (GET_MODE_SIZE (is_mode)
2067 - GET_MODE_SIZE (wanted_mode) - offset);
2069 pos %= GET_MODE_BITSIZE (wanted_mode);
2071 newmem = adjust_address_nv (tem, wanted_mode, offset);
2073 /* Make the change and see if the insn remains valid. */
2074 INSN_CODE (insn) = -1;
2075 XEXP (x, 0) = newmem;
2076 XEXP (x, 2) = GEN_INT (pos);
2078 if (recog_memoized (insn) >= 0)
2079 return;
2081 /* Otherwise, restore old position. XEXP (x, 0) will be
2082 restored later. */
2083 XEXP (x, 2) = old_pos;
2087 /* If we get here, the bitfield extract insn can't accept a memory
2088 reference. Copy the input into a register. */
2090 tem1 = gen_reg_rtx (GET_MODE (tem));
2091 emit_insn_before (gen_move_insn (tem1, tem), insn);
2092 XEXP (x, 0) = tem1;
2093 return;
2095 break;
2097 case SUBREG:
2098 if (SUBREG_REG (x) == var)
2100 /* If this is a special SUBREG made because VAR was promoted
2101 from a wider mode, replace it with VAR and call ourself
2102 recursively, this time saying that the object previously
2103 had its current mode (by virtue of the SUBREG). */
2105 if (SUBREG_PROMOTED_VAR_P (x))
2107 *loc = var;
2108 fixup_var_refs_1 (var, GET_MODE (var), loc, insn, replacements,
2109 no_share);
2110 return;
2113 /* If this SUBREG makes VAR wider, it has become a paradoxical
2114 SUBREG with VAR in memory, but these aren't allowed at this
2115 stage of the compilation. So load VAR into a pseudo and take
2116 a SUBREG of that pseudo. */
2117 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (var)))
2119 replacement = find_fixup_replacement (replacements, var);
2120 if (replacement->new == 0)
2121 replacement->new = gen_reg_rtx (promoted_mode);
2122 SUBREG_REG (x) = replacement->new;
2123 return;
2126 /* See if we have already found a replacement for this SUBREG.
2127 If so, use it. Otherwise, make a MEM and see if the insn
2128 is recognized. If not, or if we should force MEM into a register,
2129 make a pseudo for this SUBREG. */
2130 replacement = find_fixup_replacement (replacements, x);
2131 if (replacement->new)
2133 *loc = replacement->new;
2134 return;
2137 replacement->new = *loc = fixup_memory_subreg (x, insn,
2138 promoted_mode, 0);
2140 INSN_CODE (insn) = -1;
2141 if (! flag_force_mem && recog_memoized (insn) >= 0)
2142 return;
2144 *loc = replacement->new = gen_reg_rtx (GET_MODE (x));
2145 return;
2147 break;
2149 case SET:
2150 /* First do special simplification of bit-field references. */
2151 if (GET_CODE (SET_DEST (x)) == SIGN_EXTRACT
2152 || GET_CODE (SET_DEST (x)) == ZERO_EXTRACT)
2153 optimize_bit_field (x, insn, 0);
2154 if (GET_CODE (SET_SRC (x)) == SIGN_EXTRACT
2155 || GET_CODE (SET_SRC (x)) == ZERO_EXTRACT)
2156 optimize_bit_field (x, insn, 0);
2158 /* For a paradoxical SUBREG inside a ZERO_EXTRACT, load the object
2159 into a register and then store it back out. */
2160 if (GET_CODE (SET_DEST (x)) == ZERO_EXTRACT
2161 && GET_CODE (XEXP (SET_DEST (x), 0)) == SUBREG
2162 && SUBREG_REG (XEXP (SET_DEST (x), 0)) == var
2163 && (GET_MODE_SIZE (GET_MODE (XEXP (SET_DEST (x), 0)))
2164 > GET_MODE_SIZE (GET_MODE (var))))
2166 replacement = find_fixup_replacement (replacements, var);
2167 if (replacement->new == 0)
2168 replacement->new = gen_reg_rtx (GET_MODE (var));
2170 SUBREG_REG (XEXP (SET_DEST (x), 0)) = replacement->new;
2171 emit_insn_after (gen_move_insn (var, replacement->new), insn);
2174 /* If SET_DEST is now a paradoxical SUBREG, put the result of this
2175 insn into a pseudo and store the low part of the pseudo into VAR. */
2176 if (GET_CODE (SET_DEST (x)) == SUBREG
2177 && SUBREG_REG (SET_DEST (x)) == var
2178 && (GET_MODE_SIZE (GET_MODE (SET_DEST (x)))
2179 > GET_MODE_SIZE (GET_MODE (var))))
2181 SET_DEST (x) = tem = gen_reg_rtx (GET_MODE (SET_DEST (x)));
2182 emit_insn_after (gen_move_insn (var, gen_lowpart (GET_MODE (var),
2183 tem)),
2184 insn);
2185 break;
2189 rtx dest = SET_DEST (x);
2190 rtx src = SET_SRC (x);
2191 rtx outerdest = dest;
2193 while (GET_CODE (dest) == SUBREG || GET_CODE (dest) == STRICT_LOW_PART
2194 || GET_CODE (dest) == SIGN_EXTRACT
2195 || GET_CODE (dest) == ZERO_EXTRACT)
2196 dest = XEXP (dest, 0);
2198 if (GET_CODE (src) == SUBREG)
2199 src = SUBREG_REG (src);
2201 /* If VAR does not appear at the top level of the SET
2202 just scan the lower levels of the tree. */
2204 if (src != var && dest != var)
2205 break;
2207 /* We will need to rerecognize this insn. */
2208 INSN_CODE (insn) = -1;
2210 if (GET_CODE (outerdest) == ZERO_EXTRACT && dest == var
2211 && mode_for_extraction (EP_insv, -1) != MAX_MACHINE_MODE)
2213 /* Since this case will return, ensure we fixup all the
2214 operands here. */
2215 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 1),
2216 insn, replacements, no_share);
2217 fixup_var_refs_1 (var, promoted_mode, &XEXP (outerdest, 2),
2218 insn, replacements, no_share);
2219 fixup_var_refs_1 (var, promoted_mode, &SET_SRC (x),
2220 insn, replacements, no_share);
2222 tem = XEXP (outerdest, 0);
2224 /* Clean up (SUBREG:SI (MEM:mode ...) 0)
2225 that may appear inside a ZERO_EXTRACT.
2226 This was legitimate when the MEM was a REG. */
2227 if (GET_CODE (tem) == SUBREG
2228 && SUBREG_REG (tem) == var)
2229 tem = fixup_memory_subreg (tem, insn, promoted_mode, 0);
2230 else
2231 tem = fixup_stack_1 (tem, insn);
2233 if (GET_CODE (XEXP (outerdest, 1)) == CONST_INT
2234 && GET_CODE (XEXP (outerdest, 2)) == CONST_INT
2235 && ! mode_dependent_address_p (XEXP (tem, 0))
2236 && ! MEM_VOLATILE_P (tem))
2238 enum machine_mode wanted_mode;
2239 enum machine_mode is_mode = GET_MODE (tem);
2240 HOST_WIDE_INT pos = INTVAL (XEXP (outerdest, 2));
2242 wanted_mode = mode_for_extraction (EP_insv, 0);
2244 /* If we have a narrower mode, we can do something. */
2245 if (GET_MODE_SIZE (wanted_mode) < GET_MODE_SIZE (is_mode))
2247 HOST_WIDE_INT offset = pos / BITS_PER_UNIT;
2248 rtx old_pos = XEXP (outerdest, 2);
2249 rtx newmem;
2251 if (BYTES_BIG_ENDIAN != BITS_BIG_ENDIAN)
2252 offset = (GET_MODE_SIZE (is_mode)
2253 - GET_MODE_SIZE (wanted_mode) - offset);
2255 pos %= GET_MODE_BITSIZE (wanted_mode);
2257 newmem = adjust_address_nv (tem, wanted_mode, offset);
2259 /* Make the change and see if the insn remains valid. */
2260 INSN_CODE (insn) = -1;
2261 XEXP (outerdest, 0) = newmem;
2262 XEXP (outerdest, 2) = GEN_INT (pos);
2264 if (recog_memoized (insn) >= 0)
2265 return;
2267 /* Otherwise, restore old position. XEXP (x, 0) will be
2268 restored later. */
2269 XEXP (outerdest, 2) = old_pos;
2273 /* If we get here, the bit-field store doesn't allow memory
2274 or isn't located at a constant position. Load the value into
2275 a register, do the store, and put it back into memory. */
2277 tem1 = gen_reg_rtx (GET_MODE (tem));
2278 emit_insn_before (gen_move_insn (tem1, tem), insn);
2279 emit_insn_after (gen_move_insn (tem, tem1), insn);
2280 XEXP (outerdest, 0) = tem1;
2281 return;
2284 /* STRICT_LOW_PART is a no-op on memory references
2285 and it can cause combinations to be unrecognizable,
2286 so eliminate it. */
2288 if (dest == var && GET_CODE (SET_DEST (x)) == STRICT_LOW_PART)
2289 SET_DEST (x) = XEXP (SET_DEST (x), 0);
2291 /* A valid insn to copy VAR into or out of a register
2292 must be left alone, to avoid an infinite loop here.
2293 If the reference to VAR is by a subreg, fix that up,
2294 since SUBREG is not valid for a memref.
2295 Also fix up the address of the stack slot.
2297 Note that we must not try to recognize the insn until
2298 after we know that we have valid addresses and no
2299 (subreg (mem ...) ...) constructs, since these interfere
2300 with determining the validity of the insn. */
2302 if ((SET_SRC (x) == var
2303 || (GET_CODE (SET_SRC (x)) == SUBREG
2304 && SUBREG_REG (SET_SRC (x)) == var))
2305 && (GET_CODE (SET_DEST (x)) == REG
2306 || (GET_CODE (SET_DEST (x)) == SUBREG
2307 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG))
2308 && GET_MODE (var) == promoted_mode
2309 && x == single_set (insn))
2311 rtx pat, last;
2313 if (GET_CODE (SET_SRC (x)) == SUBREG
2314 && (GET_MODE_SIZE (GET_MODE (SET_SRC (x)))
2315 > GET_MODE_SIZE (GET_MODE (var))))
2317 /* This (subreg VAR) is now a paradoxical subreg. We need
2318 to replace VAR instead of the subreg. */
2319 replacement = find_fixup_replacement (replacements, var);
2320 if (replacement->new == NULL_RTX)
2321 replacement->new = gen_reg_rtx (GET_MODE (var));
2322 SUBREG_REG (SET_SRC (x)) = replacement->new;
2324 else
2326 replacement = find_fixup_replacement (replacements, SET_SRC (x));
2327 if (replacement->new)
2328 SET_SRC (x) = replacement->new;
2329 else if (GET_CODE (SET_SRC (x)) == SUBREG)
2330 SET_SRC (x) = replacement->new
2331 = fixup_memory_subreg (SET_SRC (x), insn, promoted_mode,
2333 else
2334 SET_SRC (x) = replacement->new
2335 = fixup_stack_1 (SET_SRC (x), insn);
2338 if (recog_memoized (insn) >= 0)
2339 return;
2341 /* INSN is not valid, but we know that we want to
2342 copy SET_SRC (x) to SET_DEST (x) in some way. So
2343 we generate the move and see whether it requires more
2344 than one insn. If it does, we emit those insns and
2345 delete INSN. Otherwise, we can just replace the pattern
2346 of INSN; we have already verified above that INSN has
2347 no other function that to do X. */
2349 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2350 if (NEXT_INSN (pat) != NULL_RTX)
2352 last = emit_insn_before (pat, insn);
2354 /* INSN might have REG_RETVAL or other important notes, so
2355 we need to store the pattern of the last insn in the
2356 sequence into INSN similarly to the normal case. LAST
2357 should not have REG_NOTES, but we allow them if INSN has
2358 no REG_NOTES. */
2359 if (REG_NOTES (last) && REG_NOTES (insn))
2360 abort ();
2361 if (REG_NOTES (last))
2362 REG_NOTES (insn) = REG_NOTES (last);
2363 PATTERN (insn) = PATTERN (last);
2365 delete_insn (last);
2367 else
2368 PATTERN (insn) = PATTERN (pat);
2370 return;
2373 if ((SET_DEST (x) == var
2374 || (GET_CODE (SET_DEST (x)) == SUBREG
2375 && SUBREG_REG (SET_DEST (x)) == var))
2376 && (GET_CODE (SET_SRC (x)) == REG
2377 || (GET_CODE (SET_SRC (x)) == SUBREG
2378 && GET_CODE (SUBREG_REG (SET_SRC (x))) == REG))
2379 && GET_MODE (var) == promoted_mode
2380 && x == single_set (insn))
2382 rtx pat, last;
2384 if (GET_CODE (SET_DEST (x)) == SUBREG)
2385 SET_DEST (x) = fixup_memory_subreg (SET_DEST (x), insn,
2386 promoted_mode, 0);
2387 else
2388 SET_DEST (x) = fixup_stack_1 (SET_DEST (x), insn);
2390 if (recog_memoized (insn) >= 0)
2391 return;
2393 pat = gen_move_insn (SET_DEST (x), SET_SRC (x));
2394 if (NEXT_INSN (pat) != NULL_RTX)
2396 last = emit_insn_before (pat, insn);
2398 /* INSN might have REG_RETVAL or other important notes, so
2399 we need to store the pattern of the last insn in the
2400 sequence into INSN similarly to the normal case. LAST
2401 should not have REG_NOTES, but we allow them if INSN has
2402 no REG_NOTES. */
2403 if (REG_NOTES (last) && REG_NOTES (insn))
2404 abort ();
2405 if (REG_NOTES (last))
2406 REG_NOTES (insn) = REG_NOTES (last);
2407 PATTERN (insn) = PATTERN (last);
2409 delete_insn (last);
2411 else
2412 PATTERN (insn) = PATTERN (pat);
2414 return;
2417 /* Otherwise, storing into VAR must be handled specially
2418 by storing into a temporary and copying that into VAR
2419 with a new insn after this one. Note that this case
2420 will be used when storing into a promoted scalar since
2421 the insn will now have different modes on the input
2422 and output and hence will be invalid (except for the case
2423 of setting it to a constant, which does not need any
2424 change if it is valid). We generate extra code in that case,
2425 but combine.c will eliminate it. */
2427 if (dest == var)
2429 rtx temp;
2430 rtx fixeddest = SET_DEST (x);
2431 enum machine_mode temp_mode;
2433 /* STRICT_LOW_PART can be discarded, around a MEM. */
2434 if (GET_CODE (fixeddest) == STRICT_LOW_PART)
2435 fixeddest = XEXP (fixeddest, 0);
2436 /* Convert (SUBREG (MEM)) to a MEM in a changed mode. */
2437 if (GET_CODE (fixeddest) == SUBREG)
2439 fixeddest = fixup_memory_subreg (fixeddest, insn,
2440 promoted_mode, 0);
2441 temp_mode = GET_MODE (fixeddest);
2443 else
2445 fixeddest = fixup_stack_1 (fixeddest, insn);
2446 temp_mode = promoted_mode;
2449 temp = gen_reg_rtx (temp_mode);
2451 emit_insn_after (gen_move_insn (fixeddest,
2452 gen_lowpart (GET_MODE (fixeddest),
2453 temp)),
2454 insn);
2456 SET_DEST (x) = temp;
2460 default:
2461 break;
2464 /* Nothing special about this RTX; fix its operands. */
2466 fmt = GET_RTX_FORMAT (code);
2467 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2469 if (fmt[i] == 'e')
2470 fixup_var_refs_1 (var, promoted_mode, &XEXP (x, i), insn, replacements,
2471 no_share);
2472 else if (fmt[i] == 'E')
2474 int j;
2475 for (j = 0; j < XVECLEN (x, i); j++)
2476 fixup_var_refs_1 (var, promoted_mode, &XVECEXP (x, i, j),
2477 insn, replacements, no_share);
2482 /* Previously, X had the form (SUBREG:m1 (REG:PROMOTED_MODE ...)).
2483 The REG was placed on the stack, so X now has the form (SUBREG:m1
2484 (MEM:m2 ...)).
2486 Return an rtx (MEM:m1 newaddr) which is equivalent. If any insns
2487 must be emitted to compute NEWADDR, put them before INSN.
2489 UNCRITICAL nonzero means accept paradoxical subregs.
2490 This is used for subregs found inside REG_NOTES. */
2492 static rtx
2493 fixup_memory_subreg (x, insn, promoted_mode, uncritical)
2494 rtx x;
2495 rtx insn;
2496 enum machine_mode promoted_mode;
2497 int uncritical;
2499 int offset;
2500 rtx mem = SUBREG_REG (x);
2501 rtx addr = XEXP (mem, 0);
2502 enum machine_mode mode = GET_MODE (x);
2503 rtx result, seq;
2505 /* Paradoxical SUBREGs are usually invalid during RTL generation. */
2506 if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (mem)) && ! uncritical)
2507 abort ();
2509 offset = SUBREG_BYTE (x);
2510 if (BYTES_BIG_ENDIAN)
2511 /* If the PROMOTED_MODE is wider than the mode of the MEM, adjust
2512 the offset so that it points to the right location within the
2513 MEM. */
2514 offset -= (GET_MODE_SIZE (promoted_mode) - GET_MODE_SIZE (GET_MODE (mem)));
2516 if (!flag_force_addr
2517 && memory_address_p (mode, plus_constant (addr, offset)))
2518 /* Shortcut if no insns need be emitted. */
2519 return adjust_address (mem, mode, offset);
2521 start_sequence ();
2522 result = adjust_address (mem, mode, offset);
2523 seq = get_insns ();
2524 end_sequence ();
2526 emit_insn_before (seq, insn);
2527 return result;
2530 /* Do fixup_memory_subreg on all (SUBREG (MEM ...) ...) contained in X.
2531 Replace subexpressions of X in place.
2532 If X itself is a (SUBREG (MEM ...) ...), return the replacement expression.
2533 Otherwise return X, with its contents possibly altered.
2535 INSN, PROMOTED_MODE and UNCRITICAL are as for
2536 fixup_memory_subreg. */
2538 static rtx
2539 walk_fixup_memory_subreg (x, insn, promoted_mode, uncritical)
2540 rtx x;
2541 rtx insn;
2542 enum machine_mode promoted_mode;
2543 int uncritical;
2545 enum rtx_code code;
2546 const char *fmt;
2547 int i;
2549 if (x == 0)
2550 return 0;
2552 code = GET_CODE (x);
2554 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM)
2555 return fixup_memory_subreg (x, insn, promoted_mode, uncritical);
2557 /* Nothing special about this RTX; fix its operands. */
2559 fmt = GET_RTX_FORMAT (code);
2560 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2562 if (fmt[i] == 'e')
2563 XEXP (x, i) = walk_fixup_memory_subreg (XEXP (x, i), insn,
2564 promoted_mode, uncritical);
2565 else if (fmt[i] == 'E')
2567 int j;
2568 for (j = 0; j < XVECLEN (x, i); j++)
2569 XVECEXP (x, i, j)
2570 = walk_fixup_memory_subreg (XVECEXP (x, i, j), insn,
2571 promoted_mode, uncritical);
2574 return x;
2577 /* For each memory ref within X, if it refers to a stack slot
2578 with an out of range displacement, put the address in a temp register
2579 (emitting new insns before INSN to load these registers)
2580 and alter the memory ref to use that register.
2581 Replace each such MEM rtx with a copy, to avoid clobberage. */
2583 static rtx
2584 fixup_stack_1 (x, insn)
2585 rtx x;
2586 rtx insn;
2588 int i;
2589 RTX_CODE code = GET_CODE (x);
2590 const char *fmt;
2592 if (code == MEM)
2594 rtx ad = XEXP (x, 0);
2595 /* If we have address of a stack slot but it's not valid
2596 (displacement is too large), compute the sum in a register. */
2597 if (GET_CODE (ad) == PLUS
2598 && GET_CODE (XEXP (ad, 0)) == REG
2599 && ((REGNO (XEXP (ad, 0)) >= FIRST_VIRTUAL_REGISTER
2600 && REGNO (XEXP (ad, 0)) <= LAST_VIRTUAL_REGISTER)
2601 || REGNO (XEXP (ad, 0)) == FRAME_POINTER_REGNUM
2602 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
2603 || REGNO (XEXP (ad, 0)) == HARD_FRAME_POINTER_REGNUM
2604 #endif
2605 || REGNO (XEXP (ad, 0)) == STACK_POINTER_REGNUM
2606 || REGNO (XEXP (ad, 0)) == ARG_POINTER_REGNUM
2607 || XEXP (ad, 0) == current_function_internal_arg_pointer)
2608 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
2610 rtx temp, seq;
2611 if (memory_address_p (GET_MODE (x), ad))
2612 return x;
2614 start_sequence ();
2615 temp = copy_to_reg (ad);
2616 seq = get_insns ();
2617 end_sequence ();
2618 emit_insn_before (seq, insn);
2619 return replace_equiv_address (x, temp);
2621 return x;
2624 fmt = GET_RTX_FORMAT (code);
2625 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2627 if (fmt[i] == 'e')
2628 XEXP (x, i) = fixup_stack_1 (XEXP (x, i), insn);
2629 else if (fmt[i] == 'E')
2631 int j;
2632 for (j = 0; j < XVECLEN (x, i); j++)
2633 XVECEXP (x, i, j) = fixup_stack_1 (XVECEXP (x, i, j), insn);
2636 return x;
2639 /* Optimization: a bit-field instruction whose field
2640 happens to be a byte or halfword in memory
2641 can be changed to a move instruction.
2643 We call here when INSN is an insn to examine or store into a bit-field.
2644 BODY is the SET-rtx to be altered.
2646 EQUIV_MEM is the table `reg_equiv_mem' if that is available; else 0.
2647 (Currently this is called only from function.c, and EQUIV_MEM
2648 is always 0.) */
2650 static void
2651 optimize_bit_field (body, insn, equiv_mem)
2652 rtx body;
2653 rtx insn;
2654 rtx *equiv_mem;
2656 rtx bitfield;
2657 int destflag;
2658 rtx seq = 0;
2659 enum machine_mode mode;
2661 if (GET_CODE (SET_DEST (body)) == SIGN_EXTRACT
2662 || GET_CODE (SET_DEST (body)) == ZERO_EXTRACT)
2663 bitfield = SET_DEST (body), destflag = 1;
2664 else
2665 bitfield = SET_SRC (body), destflag = 0;
2667 /* First check that the field being stored has constant size and position
2668 and is in fact a byte or halfword suitably aligned. */
2670 if (GET_CODE (XEXP (bitfield, 1)) == CONST_INT
2671 && GET_CODE (XEXP (bitfield, 2)) == CONST_INT
2672 && ((mode = mode_for_size (INTVAL (XEXP (bitfield, 1)), MODE_INT, 1))
2673 != BLKmode)
2674 && INTVAL (XEXP (bitfield, 2)) % INTVAL (XEXP (bitfield, 1)) == 0)
2676 rtx memref = 0;
2678 /* Now check that the containing word is memory, not a register,
2679 and that it is safe to change the machine mode. */
2681 if (GET_CODE (XEXP (bitfield, 0)) == MEM)
2682 memref = XEXP (bitfield, 0);
2683 else if (GET_CODE (XEXP (bitfield, 0)) == REG
2684 && equiv_mem != 0)
2685 memref = equiv_mem[REGNO (XEXP (bitfield, 0))];
2686 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2687 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == MEM)
2688 memref = SUBREG_REG (XEXP (bitfield, 0));
2689 else if (GET_CODE (XEXP (bitfield, 0)) == SUBREG
2690 && equiv_mem != 0
2691 && GET_CODE (SUBREG_REG (XEXP (bitfield, 0))) == REG)
2692 memref = equiv_mem[REGNO (SUBREG_REG (XEXP (bitfield, 0)))];
2694 if (memref
2695 && ! mode_dependent_address_p (XEXP (memref, 0))
2696 && ! MEM_VOLATILE_P (memref))
2698 /* Now adjust the address, first for any subreg'ing
2699 that we are now getting rid of,
2700 and then for which byte of the word is wanted. */
2702 HOST_WIDE_INT offset = INTVAL (XEXP (bitfield, 2));
2703 rtx insns;
2705 /* Adjust OFFSET to count bits from low-address byte. */
2706 if (BITS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
2707 offset = (GET_MODE_BITSIZE (GET_MODE (XEXP (bitfield, 0)))
2708 - offset - INTVAL (XEXP (bitfield, 1)));
2710 /* Adjust OFFSET to count bytes from low-address byte. */
2711 offset /= BITS_PER_UNIT;
2712 if (GET_CODE (XEXP (bitfield, 0)) == SUBREG)
2714 offset += (SUBREG_BYTE (XEXP (bitfield, 0))
2715 / UNITS_PER_WORD) * UNITS_PER_WORD;
2716 if (BYTES_BIG_ENDIAN)
2717 offset -= (MIN (UNITS_PER_WORD,
2718 GET_MODE_SIZE (GET_MODE (XEXP (bitfield, 0))))
2719 - MIN (UNITS_PER_WORD,
2720 GET_MODE_SIZE (GET_MODE (memref))));
2723 start_sequence ();
2724 memref = adjust_address (memref, mode, offset);
2725 insns = get_insns ();
2726 end_sequence ();
2727 emit_insn_before (insns, insn);
2729 /* Store this memory reference where
2730 we found the bit field reference. */
2732 if (destflag)
2734 validate_change (insn, &SET_DEST (body), memref, 1);
2735 if (! CONSTANT_ADDRESS_P (SET_SRC (body)))
2737 rtx src = SET_SRC (body);
2738 while (GET_CODE (src) == SUBREG
2739 && SUBREG_BYTE (src) == 0)
2740 src = SUBREG_REG (src);
2741 if (GET_MODE (src) != GET_MODE (memref))
2742 src = gen_lowpart (GET_MODE (memref), SET_SRC (body));
2743 validate_change (insn, &SET_SRC (body), src, 1);
2745 else if (GET_MODE (SET_SRC (body)) != VOIDmode
2746 && GET_MODE (SET_SRC (body)) != GET_MODE (memref))
2747 /* This shouldn't happen because anything that didn't have
2748 one of these modes should have got converted explicitly
2749 and then referenced through a subreg.
2750 This is so because the original bit-field was
2751 handled by agg_mode and so its tree structure had
2752 the same mode that memref now has. */
2753 abort ();
2755 else
2757 rtx dest = SET_DEST (body);
2759 while (GET_CODE (dest) == SUBREG
2760 && SUBREG_BYTE (dest) == 0
2761 && (GET_MODE_CLASS (GET_MODE (dest))
2762 == GET_MODE_CLASS (GET_MODE (SUBREG_REG (dest))))
2763 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
2764 <= UNITS_PER_WORD))
2765 dest = SUBREG_REG (dest);
2767 validate_change (insn, &SET_DEST (body), dest, 1);
2769 if (GET_MODE (dest) == GET_MODE (memref))
2770 validate_change (insn, &SET_SRC (body), memref, 1);
2771 else
2773 /* Convert the mem ref to the destination mode. */
2774 rtx newreg = gen_reg_rtx (GET_MODE (dest));
2776 start_sequence ();
2777 convert_move (newreg, memref,
2778 GET_CODE (SET_SRC (body)) == ZERO_EXTRACT);
2779 seq = get_insns ();
2780 end_sequence ();
2782 validate_change (insn, &SET_SRC (body), newreg, 1);
2786 /* See if we can convert this extraction or insertion into
2787 a simple move insn. We might not be able to do so if this
2788 was, for example, part of a PARALLEL.
2790 If we succeed, write out any needed conversions. If we fail,
2791 it is hard to guess why we failed, so don't do anything
2792 special; just let the optimization be suppressed. */
2794 if (apply_change_group () && seq)
2795 emit_insn_before (seq, insn);
2800 /* These routines are responsible for converting virtual register references
2801 to the actual hard register references once RTL generation is complete.
2803 The following four variables are used for communication between the
2804 routines. They contain the offsets of the virtual registers from their
2805 respective hard registers. */
2807 static int in_arg_offset;
2808 static int var_offset;
2809 static int dynamic_offset;
2810 static int out_arg_offset;
2811 static int cfa_offset;
2813 /* In most machines, the stack pointer register is equivalent to the bottom
2814 of the stack. */
2816 #ifndef STACK_POINTER_OFFSET
2817 #define STACK_POINTER_OFFSET 0
2818 #endif
2820 /* If not defined, pick an appropriate default for the offset of dynamically
2821 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
2822 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
2824 #ifndef STACK_DYNAMIC_OFFSET
2826 /* The bottom of the stack points to the actual arguments. If
2827 REG_PARM_STACK_SPACE is defined, this includes the space for the register
2828 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
2829 stack space for register parameters is not pushed by the caller, but
2830 rather part of the fixed stack areas and hence not included in
2831 `current_function_outgoing_args_size'. Nevertheless, we must allow
2832 for it when allocating stack dynamic objects. */
2834 #if defined(REG_PARM_STACK_SPACE) && ! defined(OUTGOING_REG_PARM_STACK_SPACE)
2835 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2836 ((ACCUMULATE_OUTGOING_ARGS \
2837 ? (current_function_outgoing_args_size + REG_PARM_STACK_SPACE (FNDECL)) : 0)\
2838 + (STACK_POINTER_OFFSET)) \
2840 #else
2841 #define STACK_DYNAMIC_OFFSET(FNDECL) \
2842 ((ACCUMULATE_OUTGOING_ARGS ? current_function_outgoing_args_size : 0) \
2843 + (STACK_POINTER_OFFSET))
2844 #endif
2845 #endif
2847 /* On most machines, the CFA coincides with the first incoming parm. */
2849 #ifndef ARG_POINTER_CFA_OFFSET
2850 #define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
2851 #endif
2853 /* Build up a (MEM (ADDRESSOF (REG))) rtx for a register REG that just had its
2854 address taken. DECL is the decl or SAVE_EXPR for the object stored in the
2855 register, for later use if we do need to force REG into the stack. REG is
2856 overwritten by the MEM like in put_reg_into_stack. */
2859 gen_mem_addressof (reg, decl)
2860 rtx reg;
2861 tree decl;
2863 rtx r = gen_rtx_ADDRESSOF (Pmode, gen_reg_rtx (GET_MODE (reg)),
2864 REGNO (reg), decl);
2866 /* Calculate this before we start messing with decl's RTL. */
2867 HOST_WIDE_INT set = decl ? get_alias_set (decl) : 0;
2869 /* If the original REG was a user-variable, then so is the REG whose
2870 address is being taken. Likewise for unchanging. */
2871 REG_USERVAR_P (XEXP (r, 0)) = REG_USERVAR_P (reg);
2872 RTX_UNCHANGING_P (XEXP (r, 0)) = RTX_UNCHANGING_P (reg);
2874 PUT_CODE (reg, MEM);
2875 MEM_ATTRS (reg) = 0;
2876 XEXP (reg, 0) = r;
2878 if (decl)
2880 tree type = TREE_TYPE (decl);
2881 enum machine_mode decl_mode
2882 = (DECL_P (decl) ? DECL_MODE (decl) : TYPE_MODE (TREE_TYPE (decl)));
2883 rtx decl_rtl = (TREE_CODE (decl) == SAVE_EXPR ? SAVE_EXPR_RTL (decl)
2884 : DECL_RTL_IF_SET (decl));
2886 PUT_MODE (reg, decl_mode);
2888 /* Clear DECL_RTL momentarily so functions below will work
2889 properly, then set it again. */
2890 if (DECL_P (decl) && decl_rtl == reg)
2891 SET_DECL_RTL (decl, 0);
2893 set_mem_attributes (reg, decl, 1);
2894 set_mem_alias_set (reg, set);
2896 if (DECL_P (decl) && decl_rtl == reg)
2897 SET_DECL_RTL (decl, reg);
2899 if (TREE_USED (decl) || (DECL_P (decl) && DECL_INITIAL (decl) != 0))
2900 fixup_var_refs (reg, GET_MODE (reg), TREE_UNSIGNED (type), reg, 0);
2902 else
2903 fixup_var_refs (reg, GET_MODE (reg), 0, reg, 0);
2905 return reg;
2908 /* If DECL has an RTL that is an ADDRESSOF rtx, put it into the stack. */
2910 void
2911 flush_addressof (decl)
2912 tree decl;
2914 if ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == VAR_DECL)
2915 && DECL_RTL (decl) != 0
2916 && GET_CODE (DECL_RTL (decl)) == MEM
2917 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF
2918 && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == REG)
2919 put_addressof_into_stack (XEXP (DECL_RTL (decl), 0), 0);
2922 /* Force the register pointed to by R, an ADDRESSOF rtx, into the stack. */
2924 static void
2925 put_addressof_into_stack (r, ht)
2926 rtx r;
2927 htab_t ht;
2929 tree decl, type;
2930 int volatile_p, used_p;
2932 rtx reg = XEXP (r, 0);
2934 if (GET_CODE (reg) != REG)
2935 abort ();
2937 decl = ADDRESSOF_DECL (r);
2938 if (decl)
2940 type = TREE_TYPE (decl);
2941 volatile_p = (TREE_CODE (decl) != SAVE_EXPR
2942 && TREE_THIS_VOLATILE (decl));
2943 used_p = (TREE_USED (decl)
2944 || (DECL_P (decl) && DECL_INITIAL (decl) != 0));
2946 else
2948 type = NULL_TREE;
2949 volatile_p = 0;
2950 used_p = 1;
2953 put_reg_into_stack (0, reg, type, GET_MODE (reg), GET_MODE (reg),
2954 volatile_p, ADDRESSOF_REGNO (r), used_p, ht);
2957 /* List of replacements made below in purge_addressof_1 when creating
2958 bitfield insertions. */
2959 static rtx purge_bitfield_addressof_replacements;
2961 /* List of replacements made below in purge_addressof_1 for patterns
2962 (MEM (ADDRESSOF (REG ...))). The key of the list entry is the
2963 corresponding (ADDRESSOF (REG ...)) and value is a substitution for
2964 the all pattern. List PURGE_BITFIELD_ADDRESSOF_REPLACEMENTS is not
2965 enough in complex cases, e.g. when some field values can be
2966 extracted by usage MEM with narrower mode. */
2967 static rtx purge_addressof_replacements;
2969 /* Helper function for purge_addressof. See if the rtx expression at *LOC
2970 in INSN needs to be changed. If FORCE, always put any ADDRESSOFs into
2971 the stack. If the function returns FALSE then the replacement could not
2972 be made. */
2974 static bool
2975 purge_addressof_1 (loc, insn, force, store, ht)
2976 rtx *loc;
2977 rtx insn;
2978 int force, store;
2979 htab_t ht;
2981 rtx x;
2982 RTX_CODE code;
2983 int i, j;
2984 const char *fmt;
2985 bool result = true;
2987 /* Re-start here to avoid recursion in common cases. */
2988 restart:
2990 x = *loc;
2991 if (x == 0)
2992 return true;
2994 code = GET_CODE (x);
2996 /* If we don't return in any of the cases below, we will recurse inside
2997 the RTX, which will normally result in any ADDRESSOF being forced into
2998 memory. */
2999 if (code == SET)
3001 result = purge_addressof_1 (&SET_DEST (x), insn, force, 1, ht);
3002 result &= purge_addressof_1 (&SET_SRC (x), insn, force, 0, ht);
3003 return result;
3005 else if (code == ADDRESSOF)
3007 rtx sub, insns;
3009 if (GET_CODE (XEXP (x, 0)) != MEM)
3010 put_addressof_into_stack (x, ht);
3012 /* We must create a copy of the rtx because it was created by
3013 overwriting a REG rtx which is always shared. */
3014 sub = copy_rtx (XEXP (XEXP (x, 0), 0));
3015 if (validate_change (insn, loc, sub, 0)
3016 || validate_replace_rtx (x, sub, insn))
3017 return true;
3019 start_sequence ();
3020 sub = force_operand (sub, NULL_RTX);
3021 if (! validate_change (insn, loc, sub, 0)
3022 && ! validate_replace_rtx (x, sub, insn))
3023 abort ();
3025 insns = get_insns ();
3026 end_sequence ();
3027 emit_insn_before (insns, insn);
3028 return true;
3031 else if (code == MEM && GET_CODE (XEXP (x, 0)) == ADDRESSOF && ! force)
3033 rtx sub = XEXP (XEXP (x, 0), 0);
3035 if (GET_CODE (sub) == MEM)
3036 sub = adjust_address_nv (sub, GET_MODE (x), 0);
3037 else if (GET_CODE (sub) == REG
3038 && (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode))
3040 else if (GET_CODE (sub) == REG && GET_MODE (x) != GET_MODE (sub))
3042 int size_x, size_sub;
3044 if (!insn)
3046 /* When processing REG_NOTES look at the list of
3047 replacements done on the insn to find the register that X
3048 was replaced by. */
3049 rtx tem;
3051 for (tem = purge_bitfield_addressof_replacements;
3052 tem != NULL_RTX;
3053 tem = XEXP (XEXP (tem, 1), 1))
3054 if (rtx_equal_p (x, XEXP (tem, 0)))
3056 *loc = XEXP (XEXP (tem, 1), 0);
3057 return true;
3060 /* See comment for purge_addressof_replacements. */
3061 for (tem = purge_addressof_replacements;
3062 tem != NULL_RTX;
3063 tem = XEXP (XEXP (tem, 1), 1))
3064 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3066 rtx z = XEXP (XEXP (tem, 1), 0);
3068 if (GET_MODE (x) == GET_MODE (z)
3069 || (GET_CODE (XEXP (XEXP (tem, 1), 0)) != REG
3070 && GET_CODE (XEXP (XEXP (tem, 1), 0)) != SUBREG))
3071 abort ();
3073 /* It can happen that the note may speak of things
3074 in a wider (or just different) mode than the
3075 code did. This is especially true of
3076 REG_RETVAL. */
3078 if (GET_CODE (z) == SUBREG && SUBREG_BYTE (z) == 0)
3079 z = SUBREG_REG (z);
3081 if (GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
3082 && (GET_MODE_SIZE (GET_MODE (x))
3083 > GET_MODE_SIZE (GET_MODE (z))))
3085 /* This can occur as a result in invalid
3086 pointer casts, e.g. float f; ...
3087 *(long long int *)&f.
3088 ??? We could emit a warning here, but
3089 without a line number that wouldn't be
3090 very helpful. */
3091 z = gen_rtx_SUBREG (GET_MODE (x), z, 0);
3093 else
3094 z = gen_lowpart (GET_MODE (x), z);
3096 *loc = z;
3097 return true;
3100 /* Sometimes we may not be able to find the replacement. For
3101 example when the original insn was a MEM in a wider mode,
3102 and the note is part of a sign extension of a narrowed
3103 version of that MEM. Gcc testcase compile/990829-1.c can
3104 generate an example of this situation. Rather than complain
3105 we return false, which will prompt our caller to remove the
3106 offending note. */
3107 return false;
3110 size_x = GET_MODE_BITSIZE (GET_MODE (x));
3111 size_sub = GET_MODE_BITSIZE (GET_MODE (sub));
3113 /* Don't even consider working with paradoxical subregs,
3114 or the moral equivalent seen here. */
3115 if (size_x <= size_sub
3116 && int_mode_for_mode (GET_MODE (sub)) != BLKmode)
3118 /* Do a bitfield insertion to mirror what would happen
3119 in memory. */
3121 rtx val, seq;
3123 if (store)
3125 rtx p = PREV_INSN (insn);
3127 start_sequence ();
3128 val = gen_reg_rtx (GET_MODE (x));
3129 if (! validate_change (insn, loc, val, 0))
3131 /* Discard the current sequence and put the
3132 ADDRESSOF on stack. */
3133 end_sequence ();
3134 goto give_up;
3136 seq = get_insns ();
3137 end_sequence ();
3138 emit_insn_before (seq, insn);
3139 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3140 insn, ht);
3142 start_sequence ();
3143 store_bit_field (sub, size_x, 0, GET_MODE (x),
3144 val, GET_MODE_SIZE (GET_MODE (sub)));
3146 /* Make sure to unshare any shared rtl that store_bit_field
3147 might have created. */
3148 unshare_all_rtl_again (get_insns ());
3150 seq = get_insns ();
3151 end_sequence ();
3152 p = emit_insn_after (seq, insn);
3153 if (NEXT_INSN (insn))
3154 compute_insns_for_mem (NEXT_INSN (insn),
3155 p ? NEXT_INSN (p) : NULL_RTX,
3156 ht);
3158 else
3160 rtx p = PREV_INSN (insn);
3162 start_sequence ();
3163 val = extract_bit_field (sub, size_x, 0, 1, NULL_RTX,
3164 GET_MODE (x), GET_MODE (x),
3165 GET_MODE_SIZE (GET_MODE (sub)));
3167 if (! validate_change (insn, loc, val, 0))
3169 /* Discard the current sequence and put the
3170 ADDRESSOF on stack. */
3171 end_sequence ();
3172 goto give_up;
3175 seq = get_insns ();
3176 end_sequence ();
3177 emit_insn_before (seq, insn);
3178 compute_insns_for_mem (p ? NEXT_INSN (p) : get_insns (),
3179 insn, ht);
3182 /* Remember the replacement so that the same one can be done
3183 on the REG_NOTES. */
3184 purge_bitfield_addressof_replacements
3185 = gen_rtx_EXPR_LIST (VOIDmode, x,
3186 gen_rtx_EXPR_LIST
3187 (VOIDmode, val,
3188 purge_bitfield_addressof_replacements));
3190 /* We replaced with a reg -- all done. */
3191 return true;
3195 else if (validate_change (insn, loc, sub, 0))
3197 /* Remember the replacement so that the same one can be done
3198 on the REG_NOTES. */
3199 if (GET_CODE (sub) == REG || GET_CODE (sub) == SUBREG)
3201 rtx tem;
3203 for (tem = purge_addressof_replacements;
3204 tem != NULL_RTX;
3205 tem = XEXP (XEXP (tem, 1), 1))
3206 if (rtx_equal_p (XEXP (x, 0), XEXP (tem, 0)))
3208 XEXP (XEXP (tem, 1), 0) = sub;
3209 return true;
3211 purge_addressof_replacements
3212 = gen_rtx (EXPR_LIST, VOIDmode, XEXP (x, 0),
3213 gen_rtx_EXPR_LIST (VOIDmode, sub,
3214 purge_addressof_replacements));
3215 return true;
3217 goto restart;
3221 give_up:
3222 /* Scan all subexpressions. */
3223 fmt = GET_RTX_FORMAT (code);
3224 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
3226 if (*fmt == 'e')
3227 result &= purge_addressof_1 (&XEXP (x, i), insn, force, 0, ht);
3228 else if (*fmt == 'E')
3229 for (j = 0; j < XVECLEN (x, i); j++)
3230 result &= purge_addressof_1 (&XVECEXP (x, i, j), insn, force, 0, ht);
3233 return result;
3236 /* Return a hash value for K, a REG. */
3238 static hashval_t
3239 insns_for_mem_hash (k)
3240 const void * k;
3242 /* Use the address of the key for the hash value. */
3243 struct insns_for_mem_entry *m = (struct insns_for_mem_entry *) k;
3244 return htab_hash_pointer (m->key);
3247 /* Return nonzero if K1 and K2 (two REGs) are the same. */
3249 static int
3250 insns_for_mem_comp (k1, k2)
3251 const void * k1;
3252 const void * k2;
3254 struct insns_for_mem_entry *m1 = (struct insns_for_mem_entry *) k1;
3255 struct insns_for_mem_entry *m2 = (struct insns_for_mem_entry *) k2;
3256 return m1->key == m2->key;
3259 struct insns_for_mem_walk_info
3261 /* The hash table that we are using to record which INSNs use which
3262 MEMs. */
3263 htab_t ht;
3265 /* The INSN we are currently processing. */
3266 rtx insn;
3268 /* Zero if we are walking to find ADDRESSOFs, one if we are walking
3269 to find the insns that use the REGs in the ADDRESSOFs. */
3270 int pass;
3273 /* Called from compute_insns_for_mem via for_each_rtx. If R is a REG
3274 that might be used in an ADDRESSOF expression, record this INSN in
3275 the hash table given by DATA (which is really a pointer to an
3276 insns_for_mem_walk_info structure). */
3278 static int
3279 insns_for_mem_walk (r, data)
3280 rtx *r;
3281 void *data;
3283 struct insns_for_mem_walk_info *ifmwi
3284 = (struct insns_for_mem_walk_info *) data;
3285 struct insns_for_mem_entry tmp;
3286 tmp.insns = NULL_RTX;
3288 if (ifmwi->pass == 0 && *r && GET_CODE (*r) == ADDRESSOF
3289 && GET_CODE (XEXP (*r, 0)) == REG)
3291 PTR *e;
3292 tmp.key = XEXP (*r, 0);
3293 e = htab_find_slot (ifmwi->ht, &tmp, INSERT);
3294 if (*e == NULL)
3296 *e = ggc_alloc (sizeof (tmp));
3297 memcpy (*e, &tmp, sizeof (tmp));
3300 else if (ifmwi->pass == 1 && *r && GET_CODE (*r) == REG)
3302 struct insns_for_mem_entry *ifme;
3303 tmp.key = *r;
3304 ifme = (struct insns_for_mem_entry *) htab_find (ifmwi->ht, &tmp);
3306 /* If we have not already recorded this INSN, do so now. Since
3307 we process the INSNs in order, we know that if we have
3308 recorded it it must be at the front of the list. */
3309 if (ifme && (!ifme->insns || XEXP (ifme->insns, 0) != ifmwi->insn))
3310 ifme->insns = gen_rtx_EXPR_LIST (VOIDmode, ifmwi->insn,
3311 ifme->insns);
3314 return 0;
3317 /* Walk the INSNS, until we reach LAST_INSN, recording which INSNs use
3318 which REGs in HT. */
3320 static void
3321 compute_insns_for_mem (insns, last_insn, ht)
3322 rtx insns;
3323 rtx last_insn;
3324 htab_t ht;
3326 rtx insn;
3327 struct insns_for_mem_walk_info ifmwi;
3328 ifmwi.ht = ht;
3330 for (ifmwi.pass = 0; ifmwi.pass < 2; ++ifmwi.pass)
3331 for (insn = insns; insn != last_insn; insn = NEXT_INSN (insn))
3332 if (INSN_P (insn))
3334 ifmwi.insn = insn;
3335 for_each_rtx (&insn, insns_for_mem_walk, &ifmwi);
3339 /* Helper function for purge_addressof called through for_each_rtx.
3340 Returns true iff the rtl is an ADDRESSOF. */
3342 static int
3343 is_addressof (rtl, data)
3344 rtx *rtl;
3345 void *data ATTRIBUTE_UNUSED;
3347 return GET_CODE (*rtl) == ADDRESSOF;
3350 /* Eliminate all occurrences of ADDRESSOF from INSNS. Elide any remaining
3351 (MEM (ADDRESSOF)) patterns, and force any needed registers into the
3352 stack. */
3354 void
3355 purge_addressof (insns)
3356 rtx insns;
3358 rtx insn;
3359 htab_t ht;
3361 /* When we actually purge ADDRESSOFs, we turn REGs into MEMs. That
3362 requires a fixup pass over the instruction stream to correct
3363 INSNs that depended on the REG being a REG, and not a MEM. But,
3364 these fixup passes are slow. Furthermore, most MEMs are not
3365 mentioned in very many instructions. So, we speed up the process
3366 by pre-calculating which REGs occur in which INSNs; that allows
3367 us to perform the fixup passes much more quickly. */
3368 ht = htab_create_ggc (1000, insns_for_mem_hash, insns_for_mem_comp, NULL);
3369 compute_insns_for_mem (insns, NULL_RTX, ht);
3371 for (insn = insns; insn; insn = NEXT_INSN (insn))
3372 if (INSN_P (insn))
3374 if (! purge_addressof_1 (&PATTERN (insn), insn,
3375 asm_noperands (PATTERN (insn)) > 0, 0, ht))
3376 /* If we could not replace the ADDRESSOFs in the insn,
3377 something is wrong. */
3378 abort ();
3380 if (! purge_addressof_1 (&REG_NOTES (insn), NULL_RTX, 0, 0, ht))
3382 /* If we could not replace the ADDRESSOFs in the insn's notes,
3383 we can just remove the offending notes instead. */
3384 rtx note;
3386 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
3388 /* If we find a REG_RETVAL note then the insn is a libcall.
3389 Such insns must have REG_EQUAL notes as well, in order
3390 for later passes of the compiler to work. So it is not
3391 safe to delete the notes here, and instead we abort. */
3392 if (REG_NOTE_KIND (note) == REG_RETVAL)
3393 abort ();
3394 if (for_each_rtx (&note, is_addressof, NULL))
3395 remove_note (insn, note);
3400 /* Clean up. */
3401 purge_bitfield_addressof_replacements = 0;
3402 purge_addressof_replacements = 0;
3404 /* REGs are shared. purge_addressof will destructively replace a REG
3405 with a MEM, which creates shared MEMs.
3407 Unfortunately, the children of put_reg_into_stack assume that MEMs
3408 referring to the same stack slot are shared (fixup_var_refs and
3409 the associated hash table code).
3411 So, we have to do another unsharing pass after we have flushed any
3412 REGs that had their address taken into the stack.
3414 It may be worth tracking whether or not we converted any REGs into
3415 MEMs to avoid this overhead when it is not needed. */
3416 unshare_all_rtl_again (get_insns ());
3419 /* Convert a SET of a hard subreg to a set of the appropriate hard
3420 register. A subroutine of purge_hard_subreg_sets. */
3422 static void
3423 purge_single_hard_subreg_set (pattern)
3424 rtx pattern;
3426 rtx reg = SET_DEST (pattern);
3427 enum machine_mode mode = GET_MODE (SET_DEST (pattern));
3428 int offset = 0;
3430 if (GET_CODE (reg) == SUBREG && GET_CODE (SUBREG_REG (reg)) == REG
3431 && REGNO (SUBREG_REG (reg)) < FIRST_PSEUDO_REGISTER)
3433 offset = subreg_regno_offset (REGNO (SUBREG_REG (reg)),
3434 GET_MODE (SUBREG_REG (reg)),
3435 SUBREG_BYTE (reg),
3436 GET_MODE (reg));
3437 reg = SUBREG_REG (reg);
3441 if (GET_CODE (reg) == REG && REGNO (reg) < FIRST_PSEUDO_REGISTER)
3443 reg = gen_rtx_REG (mode, REGNO (reg) + offset);
3444 SET_DEST (pattern) = reg;
3448 /* Eliminate all occurrences of SETs of hard subregs from INSNS. The
3449 only such SETs that we expect to see are those left in because
3450 integrate can't handle sets of parts of a return value register.
3452 We don't use alter_subreg because we only want to eliminate subregs
3453 of hard registers. */
3455 void
3456 purge_hard_subreg_sets (insn)
3457 rtx insn;
3459 for (; insn; insn = NEXT_INSN (insn))
3461 if (INSN_P (insn))
3463 rtx pattern = PATTERN (insn);
3464 switch (GET_CODE (pattern))
3466 case SET:
3467 if (GET_CODE (SET_DEST (pattern)) == SUBREG)
3468 purge_single_hard_subreg_set (pattern);
3469 break;
3470 case PARALLEL:
3472 int j;
3473 for (j = XVECLEN (pattern, 0) - 1; j >= 0; j--)
3475 rtx inner_pattern = XVECEXP (pattern, 0, j);
3476 if (GET_CODE (inner_pattern) == SET
3477 && GET_CODE (SET_DEST (inner_pattern)) == SUBREG)
3478 purge_single_hard_subreg_set (inner_pattern);
3481 break;
3482 default:
3483 break;
3489 /* Pass through the INSNS of function FNDECL and convert virtual register
3490 references to hard register references. */
3492 void
3493 instantiate_virtual_regs (fndecl, insns)
3494 tree fndecl;
3495 rtx insns;
3497 rtx insn;
3498 unsigned int i;
3500 /* Compute the offsets to use for this function. */
3501 in_arg_offset = FIRST_PARM_OFFSET (fndecl);
3502 var_offset = STARTING_FRAME_OFFSET;
3503 dynamic_offset = STACK_DYNAMIC_OFFSET (fndecl);
3504 out_arg_offset = STACK_POINTER_OFFSET;
3505 cfa_offset = ARG_POINTER_CFA_OFFSET (fndecl);
3507 /* Scan all variables and parameters of this function. For each that is
3508 in memory, instantiate all virtual registers if the result is a valid
3509 address. If not, we do it later. That will handle most uses of virtual
3510 regs on many machines. */
3511 instantiate_decls (fndecl, 1);
3513 /* Initialize recognition, indicating that volatile is OK. */
3514 init_recog ();
3516 /* Scan through all the insns, instantiating every virtual register still
3517 present. */
3518 for (insn = insns; insn; insn = NEXT_INSN (insn))
3519 if (GET_CODE (insn) == INSN || GET_CODE (insn) == JUMP_INSN
3520 || GET_CODE (insn) == CALL_INSN)
3522 instantiate_virtual_regs_1 (&PATTERN (insn), insn, 1);
3523 instantiate_virtual_regs_1 (&REG_NOTES (insn), NULL_RTX, 0);
3524 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
3525 if (GET_CODE (insn) == CALL_INSN)
3526 instantiate_virtual_regs_1 (&CALL_INSN_FUNCTION_USAGE (insn),
3527 NULL_RTX, 0);
3530 /* Instantiate the stack slots for the parm registers, for later use in
3531 addressof elimination. */
3532 for (i = 0; i < max_parm_reg; ++i)
3533 if (parm_reg_stack_loc[i])
3534 instantiate_virtual_regs_1 (&parm_reg_stack_loc[i], NULL_RTX, 0);
3536 /* Now instantiate the remaining register equivalences for debugging info.
3537 These will not be valid addresses. */
3538 instantiate_decls (fndecl, 0);
3540 /* Indicate that, from now on, assign_stack_local should use
3541 frame_pointer_rtx. */
3542 virtuals_instantiated = 1;
3545 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
3546 all virtual registers in their DECL_RTL's.
3548 If VALID_ONLY, do this only if the resulting address is still valid.
3549 Otherwise, always do it. */
3551 static void
3552 instantiate_decls (fndecl, valid_only)
3553 tree fndecl;
3554 int valid_only;
3556 tree decl;
3558 /* Process all parameters of the function. */
3559 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
3561 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (decl));
3562 HOST_WIDE_INT size_rtl;
3564 instantiate_decl (DECL_RTL (decl), size, valid_only);
3566 /* If the parameter was promoted, then the incoming RTL mode may be
3567 larger than the declared type size. We must use the larger of
3568 the two sizes. */
3569 size_rtl = GET_MODE_SIZE (GET_MODE (DECL_INCOMING_RTL (decl)));
3570 size = MAX (size_rtl, size);
3571 instantiate_decl (DECL_INCOMING_RTL (decl), size, valid_only);
3574 /* Now process all variables defined in the function or its subblocks. */
3575 instantiate_decls_1 (DECL_INITIAL (fndecl), valid_only);
3578 /* Subroutine of instantiate_decls: Process all decls in the given
3579 BLOCK node and all its subblocks. */
3581 static void
3582 instantiate_decls_1 (let, valid_only)
3583 tree let;
3584 int valid_only;
3586 tree t;
3588 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
3589 if (DECL_RTL_SET_P (t))
3590 instantiate_decl (DECL_RTL (t),
3591 int_size_in_bytes (TREE_TYPE (t)),
3592 valid_only);
3594 /* Process all subblocks. */
3595 for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
3596 instantiate_decls_1 (t, valid_only);
3599 /* Subroutine of the preceding procedures: Given RTL representing a
3600 decl and the size of the object, do any instantiation required.
3602 If VALID_ONLY is nonzero, it means that the RTL should only be
3603 changed if the new address is valid. */
3605 static void
3606 instantiate_decl (x, size, valid_only)
3607 rtx x;
3608 HOST_WIDE_INT size;
3609 int valid_only;
3611 enum machine_mode mode;
3612 rtx addr;
3614 /* If this is not a MEM, no need to do anything. Similarly if the
3615 address is a constant or a register that is not a virtual register. */
3617 if (x == 0 || GET_CODE (x) != MEM)
3618 return;
3620 addr = XEXP (x, 0);
3621 if (CONSTANT_P (addr)
3622 || (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == REG)
3623 || (GET_CODE (addr) == REG
3624 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
3625 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
3626 return;
3628 /* If we should only do this if the address is valid, copy the address.
3629 We need to do this so we can undo any changes that might make the
3630 address invalid. This copy is unfortunate, but probably can't be
3631 avoided. */
3633 if (valid_only)
3634 addr = copy_rtx (addr);
3636 instantiate_virtual_regs_1 (&addr, NULL_RTX, 0);
3638 if (valid_only && size >= 0)
3640 unsigned HOST_WIDE_INT decl_size = size;
3642 /* Now verify that the resulting address is valid for every integer or
3643 floating-point mode up to and including SIZE bytes long. We do this
3644 since the object might be accessed in any mode and frame addresses
3645 are shared. */
3647 for (mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
3648 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3649 mode = GET_MODE_WIDER_MODE (mode))
3650 if (! memory_address_p (mode, addr))
3651 return;
3653 for (mode = GET_CLASS_NARROWEST_MODE (MODE_FLOAT);
3654 mode != VOIDmode && GET_MODE_SIZE (mode) <= decl_size;
3655 mode = GET_MODE_WIDER_MODE (mode))
3656 if (! memory_address_p (mode, addr))
3657 return;
3660 /* Put back the address now that we have updated it and we either know
3661 it is valid or we don't care whether it is valid. */
3663 XEXP (x, 0) = addr;
3666 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
3667 is a virtual register, return the equivalent hard register and set the
3668 offset indirectly through the pointer. Otherwise, return 0. */
3670 static rtx
3671 instantiate_new_reg (x, poffset)
3672 rtx x;
3673 HOST_WIDE_INT *poffset;
3675 rtx new;
3676 HOST_WIDE_INT offset;
3678 if (x == virtual_incoming_args_rtx)
3679 new = arg_pointer_rtx, offset = in_arg_offset;
3680 else if (x == virtual_stack_vars_rtx)
3681 new = frame_pointer_rtx, offset = var_offset;
3682 else if (x == virtual_stack_dynamic_rtx)
3683 new = stack_pointer_rtx, offset = dynamic_offset;
3684 else if (x == virtual_outgoing_args_rtx)
3685 new = stack_pointer_rtx, offset = out_arg_offset;
3686 else if (x == virtual_cfa_rtx)
3687 new = arg_pointer_rtx, offset = cfa_offset;
3688 else
3689 return 0;
3691 *poffset = offset;
3692 return new;
3695 /* Given a pointer to a piece of rtx and an optional pointer to the
3696 containing object, instantiate any virtual registers present in it.
3698 If EXTRA_INSNS, we always do the replacement and generate
3699 any extra insns before OBJECT. If it zero, we do nothing if replacement
3700 is not valid.
3702 Return 1 if we either had nothing to do or if we were able to do the
3703 needed replacement. Return 0 otherwise; we only return zero if
3704 EXTRA_INSNS is zero.
3706 We first try some simple transformations to avoid the creation of extra
3707 pseudos. */
3709 static int
3710 instantiate_virtual_regs_1 (loc, object, extra_insns)
3711 rtx *loc;
3712 rtx object;
3713 int extra_insns;
3715 rtx x;
3716 RTX_CODE code;
3717 rtx new = 0;
3718 HOST_WIDE_INT offset = 0;
3719 rtx temp;
3720 rtx seq;
3721 int i, j;
3722 const char *fmt;
3724 /* Re-start here to avoid recursion in common cases. */
3725 restart:
3727 x = *loc;
3728 if (x == 0)
3729 return 1;
3731 code = GET_CODE (x);
3733 /* Check for some special cases. */
3734 switch (code)
3736 case CONST_INT:
3737 case CONST_DOUBLE:
3738 case CONST_VECTOR:
3739 case CONST:
3740 case SYMBOL_REF:
3741 case CODE_LABEL:
3742 case PC:
3743 case CC0:
3744 case ASM_INPUT:
3745 case ADDR_VEC:
3746 case ADDR_DIFF_VEC:
3747 case RETURN:
3748 return 1;
3750 case SET:
3751 /* We are allowed to set the virtual registers. This means that
3752 the actual register should receive the source minus the
3753 appropriate offset. This is used, for example, in the handling
3754 of non-local gotos. */
3755 if ((new = instantiate_new_reg (SET_DEST (x), &offset)) != 0)
3757 rtx src = SET_SRC (x);
3759 /* We are setting the register, not using it, so the relevant
3760 offset is the negative of the offset to use were we using
3761 the register. */
3762 offset = - offset;
3763 instantiate_virtual_regs_1 (&src, NULL_RTX, 0);
3765 /* The only valid sources here are PLUS or REG. Just do
3766 the simplest possible thing to handle them. */
3767 if (GET_CODE (src) != REG && GET_CODE (src) != PLUS)
3768 abort ();
3770 start_sequence ();
3771 if (GET_CODE (src) != REG)
3772 temp = force_operand (src, NULL_RTX);
3773 else
3774 temp = src;
3775 temp = force_operand (plus_constant (temp, offset), NULL_RTX);
3776 seq = get_insns ();
3777 end_sequence ();
3779 emit_insn_before (seq, object);
3780 SET_DEST (x) = new;
3782 if (! validate_change (object, &SET_SRC (x), temp, 0)
3783 || ! extra_insns)
3784 abort ();
3786 return 1;
3789 instantiate_virtual_regs_1 (&SET_DEST (x), object, extra_insns);
3790 loc = &SET_SRC (x);
3791 goto restart;
3793 case PLUS:
3794 /* Handle special case of virtual register plus constant. */
3795 if (CONSTANT_P (XEXP (x, 1)))
3797 rtx old, new_offset;
3799 /* Check for (plus (plus VIRT foo) (const_int)) first. */
3800 if (GET_CODE (XEXP (x, 0)) == PLUS)
3802 if ((new = instantiate_new_reg (XEXP (XEXP (x, 0), 0), &offset)))
3804 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 1), object,
3805 extra_insns);
3806 new = gen_rtx_PLUS (Pmode, new, XEXP (XEXP (x, 0), 1));
3808 else
3810 loc = &XEXP (x, 0);
3811 goto restart;
3815 #ifdef POINTERS_EXTEND_UNSIGNED
3816 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
3817 we can commute the PLUS and SUBREG because pointers into the
3818 frame are well-behaved. */
3819 else if (GET_CODE (XEXP (x, 0)) == SUBREG && GET_MODE (x) == ptr_mode
3820 && GET_CODE (XEXP (x, 1)) == CONST_INT
3821 && 0 != (new
3822 = instantiate_new_reg (SUBREG_REG (XEXP (x, 0)),
3823 &offset))
3824 && validate_change (object, loc,
3825 plus_constant (gen_lowpart (ptr_mode,
3826 new),
3827 offset
3828 + INTVAL (XEXP (x, 1))),
3830 return 1;
3831 #endif
3832 else if ((new = instantiate_new_reg (XEXP (x, 0), &offset)) == 0)
3834 /* We know the second operand is a constant. Unless the
3835 first operand is a REG (which has been already checked),
3836 it needs to be checked. */
3837 if (GET_CODE (XEXP (x, 0)) != REG)
3839 loc = &XEXP (x, 0);
3840 goto restart;
3842 return 1;
3845 new_offset = plus_constant (XEXP (x, 1), offset);
3847 /* If the new constant is zero, try to replace the sum with just
3848 the register. */
3849 if (new_offset == const0_rtx
3850 && validate_change (object, loc, new, 0))
3851 return 1;
3853 /* Next try to replace the register and new offset.
3854 There are two changes to validate here and we can't assume that
3855 in the case of old offset equals new just changing the register
3856 will yield a valid insn. In the interests of a little efficiency,
3857 however, we only call validate change once (we don't queue up the
3858 changes and then call apply_change_group). */
3860 old = XEXP (x, 0);
3861 if (offset == 0
3862 ? ! validate_change (object, &XEXP (x, 0), new, 0)
3863 : (XEXP (x, 0) = new,
3864 ! validate_change (object, &XEXP (x, 1), new_offset, 0)))
3866 if (! extra_insns)
3868 XEXP (x, 0) = old;
3869 return 0;
3872 /* Otherwise copy the new constant into a register and replace
3873 constant with that register. */
3874 temp = gen_reg_rtx (Pmode);
3875 XEXP (x, 0) = new;
3876 if (validate_change (object, &XEXP (x, 1), temp, 0))
3877 emit_insn_before (gen_move_insn (temp, new_offset), object);
3878 else
3880 /* If that didn't work, replace this expression with a
3881 register containing the sum. */
3883 XEXP (x, 0) = old;
3884 new = gen_rtx_PLUS (Pmode, new, new_offset);
3886 start_sequence ();
3887 temp = force_operand (new, NULL_RTX);
3888 seq = get_insns ();
3889 end_sequence ();
3891 emit_insn_before (seq, object);
3892 if (! validate_change (object, loc, temp, 0)
3893 && ! validate_replace_rtx (x, temp, object))
3894 abort ();
3898 return 1;
3901 /* Fall through to generic two-operand expression case. */
3902 case EXPR_LIST:
3903 case CALL:
3904 case COMPARE:
3905 case MINUS:
3906 case MULT:
3907 case DIV: case UDIV:
3908 case MOD: case UMOD:
3909 case AND: case IOR: case XOR:
3910 case ROTATERT: case ROTATE:
3911 case ASHIFTRT: case LSHIFTRT: case ASHIFT:
3912 case NE: case EQ:
3913 case GE: case GT: case GEU: case GTU:
3914 case LE: case LT: case LEU: case LTU:
3915 if (XEXP (x, 1) && ! CONSTANT_P (XEXP (x, 1)))
3916 instantiate_virtual_regs_1 (&XEXP (x, 1), object, extra_insns);
3917 loc = &XEXP (x, 0);
3918 goto restart;
3920 case MEM:
3921 /* Most cases of MEM that convert to valid addresses have already been
3922 handled by our scan of decls. The only special handling we
3923 need here is to make a copy of the rtx to ensure it isn't being
3924 shared if we have to change it to a pseudo.
3926 If the rtx is a simple reference to an address via a virtual register,
3927 it can potentially be shared. In such cases, first try to make it
3928 a valid address, which can also be shared. Otherwise, copy it and
3929 proceed normally.
3931 First check for common cases that need no processing. These are
3932 usually due to instantiation already being done on a previous instance
3933 of a shared rtx. */
3935 temp = XEXP (x, 0);
3936 if (CONSTANT_ADDRESS_P (temp)
3937 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3938 || temp == arg_pointer_rtx
3939 #endif
3940 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3941 || temp == hard_frame_pointer_rtx
3942 #endif
3943 || temp == frame_pointer_rtx)
3944 return 1;
3946 if (GET_CODE (temp) == PLUS
3947 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3948 && (XEXP (temp, 0) == frame_pointer_rtx
3949 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
3950 || XEXP (temp, 0) == hard_frame_pointer_rtx
3951 #endif
3952 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
3953 || XEXP (temp, 0) == arg_pointer_rtx
3954 #endif
3956 return 1;
3958 if (temp == virtual_stack_vars_rtx
3959 || temp == virtual_incoming_args_rtx
3960 || (GET_CODE (temp) == PLUS
3961 && CONSTANT_ADDRESS_P (XEXP (temp, 1))
3962 && (XEXP (temp, 0) == virtual_stack_vars_rtx
3963 || XEXP (temp, 0) == virtual_incoming_args_rtx)))
3965 /* This MEM may be shared. If the substitution can be done without
3966 the need to generate new pseudos, we want to do it in place
3967 so all copies of the shared rtx benefit. The call below will
3968 only make substitutions if the resulting address is still
3969 valid.
3971 Note that we cannot pass X as the object in the recursive call
3972 since the insn being processed may not allow all valid
3973 addresses. However, if we were not passed on object, we can
3974 only modify X without copying it if X will have a valid
3975 address.
3977 ??? Also note that this can still lose if OBJECT is an insn that
3978 has less restrictions on an address that some other insn.
3979 In that case, we will modify the shared address. This case
3980 doesn't seem very likely, though. One case where this could
3981 happen is in the case of a USE or CLOBBER reference, but we
3982 take care of that below. */
3984 if (instantiate_virtual_regs_1 (&XEXP (x, 0),
3985 object ? object : x, 0))
3986 return 1;
3988 /* Otherwise make a copy and process that copy. We copy the entire
3989 RTL expression since it might be a PLUS which could also be
3990 shared. */
3991 *loc = x = copy_rtx (x);
3994 /* Fall through to generic unary operation case. */
3995 case PREFETCH:
3996 case SUBREG:
3997 case STRICT_LOW_PART:
3998 case NEG: case NOT:
3999 case PRE_DEC: case PRE_INC: case POST_DEC: case POST_INC:
4000 case SIGN_EXTEND: case ZERO_EXTEND:
4001 case TRUNCATE: case FLOAT_EXTEND: case FLOAT_TRUNCATE:
4002 case FLOAT: case FIX:
4003 case UNSIGNED_FIX: case UNSIGNED_FLOAT:
4004 case ABS:
4005 case SQRT:
4006 case FFS:
4007 /* These case either have just one operand or we know that we need not
4008 check the rest of the operands. */
4009 loc = &XEXP (x, 0);
4010 goto restart;
4012 case USE:
4013 case CLOBBER:
4014 /* If the operand is a MEM, see if the change is a valid MEM. If not,
4015 go ahead and make the invalid one, but do it to a copy. For a REG,
4016 just make the recursive call, since there's no chance of a problem. */
4018 if ((GET_CODE (XEXP (x, 0)) == MEM
4019 && instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), XEXP (x, 0),
4021 || (GET_CODE (XEXP (x, 0)) == REG
4022 && instantiate_virtual_regs_1 (&XEXP (x, 0), object, 0)))
4023 return 1;
4025 XEXP (x, 0) = copy_rtx (XEXP (x, 0));
4026 loc = &XEXP (x, 0);
4027 goto restart;
4029 case REG:
4030 /* Try to replace with a PLUS. If that doesn't work, compute the sum
4031 in front of this insn and substitute the temporary. */
4032 if ((new = instantiate_new_reg (x, &offset)) != 0)
4034 temp = plus_constant (new, offset);
4035 if (!validate_change (object, loc, temp, 0))
4037 if (! extra_insns)
4038 return 0;
4040 start_sequence ();
4041 temp = force_operand (temp, NULL_RTX);
4042 seq = get_insns ();
4043 end_sequence ();
4045 emit_insn_before (seq, object);
4046 if (! validate_change (object, loc, temp, 0)
4047 && ! validate_replace_rtx (x, temp, object))
4048 abort ();
4052 return 1;
4054 case ADDRESSOF:
4055 if (GET_CODE (XEXP (x, 0)) == REG)
4056 return 1;
4058 else if (GET_CODE (XEXP (x, 0)) == MEM)
4060 /* If we have a (addressof (mem ..)), do any instantiation inside
4061 since we know we'll be making the inside valid when we finally
4062 remove the ADDRESSOF. */
4063 instantiate_virtual_regs_1 (&XEXP (XEXP (x, 0), 0), NULL_RTX, 0);
4064 return 1;
4066 break;
4068 default:
4069 break;
4072 /* Scan all subexpressions. */
4073 fmt = GET_RTX_FORMAT (code);
4074 for (i = 0; i < GET_RTX_LENGTH (code); i++, fmt++)
4075 if (*fmt == 'e')
4077 if (!instantiate_virtual_regs_1 (&XEXP (x, i), object, extra_insns))
4078 return 0;
4080 else if (*fmt == 'E')
4081 for (j = 0; j < XVECLEN (x, i); j++)
4082 if (! instantiate_virtual_regs_1 (&XVECEXP (x, i, j), object,
4083 extra_insns))
4084 return 0;
4086 return 1;
4089 /* Optimization: assuming this function does not receive nonlocal gotos,
4090 delete the handlers for such, as well as the insns to establish
4091 and disestablish them. */
4093 static void
4094 delete_handlers ()
4096 rtx insn;
4097 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4099 /* Delete the handler by turning off the flag that would
4100 prevent jump_optimize from deleting it.
4101 Also permit deletion of the nonlocal labels themselves
4102 if nothing local refers to them. */
4103 if (GET_CODE (insn) == CODE_LABEL)
4105 tree t, last_t;
4107 LABEL_PRESERVE_P (insn) = 0;
4109 /* Remove it from the nonlocal_label list, to avoid confusing
4110 flow. */
4111 for (t = nonlocal_labels, last_t = 0; t;
4112 last_t = t, t = TREE_CHAIN (t))
4113 if (DECL_RTL (TREE_VALUE (t)) == insn)
4114 break;
4115 if (t)
4117 if (! last_t)
4118 nonlocal_labels = TREE_CHAIN (nonlocal_labels);
4119 else
4120 TREE_CHAIN (last_t) = TREE_CHAIN (t);
4123 if (GET_CODE (insn) == INSN)
4125 int can_delete = 0;
4126 rtx t;
4127 for (t = nonlocal_goto_handler_slots; t != 0; t = XEXP (t, 1))
4128 if (reg_mentioned_p (t, PATTERN (insn)))
4130 can_delete = 1;
4131 break;
4133 if (can_delete
4134 || (nonlocal_goto_stack_level != 0
4135 && reg_mentioned_p (nonlocal_goto_stack_level,
4136 PATTERN (insn))))
4137 delete_related_insns (insn);
4142 /* Return the first insn following those generated by `assign_parms'. */
4145 get_first_nonparm_insn ()
4147 if (last_parm_insn)
4148 return NEXT_INSN (last_parm_insn);
4149 return get_insns ();
4152 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
4153 This means a type for which function calls must pass an address to the
4154 function or get an address back from the function.
4155 EXP may be a type node or an expression (whose type is tested). */
4158 aggregate_value_p (exp)
4159 tree exp;
4161 int i, regno, nregs;
4162 rtx reg;
4164 tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
4166 if (TREE_CODE (type) == VOID_TYPE)
4167 return 0;
4168 if (RETURN_IN_MEMORY (type))
4169 return 1;
4170 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
4171 and thus can't be returned in registers. */
4172 if (TREE_ADDRESSABLE (type))
4173 return 1;
4174 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
4175 return 1;
4176 /* Make sure we have suitable call-clobbered regs to return
4177 the value in; if not, we must return it in memory. */
4178 reg = hard_function_value (type, 0, 0);
4180 /* If we have something other than a REG (e.g. a PARALLEL), then assume
4181 it is OK. */
4182 if (GET_CODE (reg) != REG)
4183 return 0;
4185 regno = REGNO (reg);
4186 nregs = HARD_REGNO_NREGS (regno, TYPE_MODE (type));
4187 for (i = 0; i < nregs; i++)
4188 if (! call_used_regs[regno + i])
4189 return 1;
4190 return 0;
4193 /* Assign RTL expressions to the function's parameters.
4194 This may involve copying them into registers and using
4195 those registers as the RTL for them. */
4197 void
4198 assign_parms (fndecl)
4199 tree fndecl;
4201 tree parm;
4202 rtx entry_parm = 0;
4203 rtx stack_parm = 0;
4204 CUMULATIVE_ARGS args_so_far;
4205 enum machine_mode promoted_mode, passed_mode;
4206 enum machine_mode nominal_mode, promoted_nominal_mode;
4207 int unsignedp;
4208 /* Total space needed so far for args on the stack,
4209 given as a constant and a tree-expression. */
4210 struct args_size stack_args_size;
4211 tree fntype = TREE_TYPE (fndecl);
4212 tree fnargs = DECL_ARGUMENTS (fndecl);
4213 /* This is used for the arg pointer when referring to stack args. */
4214 rtx internal_arg_pointer;
4215 /* This is a dummy PARM_DECL that we used for the function result if
4216 the function returns a structure. */
4217 tree function_result_decl = 0;
4218 #ifdef SETUP_INCOMING_VARARGS
4219 int varargs_setup = 0;
4220 #endif
4221 rtx conversion_insns = 0;
4222 struct args_size alignment_pad;
4224 /* Nonzero if function takes extra anonymous args.
4225 This means the last named arg must be on the stack
4226 right before the anonymous ones. */
4227 int stdarg
4228 = (TYPE_ARG_TYPES (fntype) != 0
4229 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4230 != void_type_node));
4232 current_function_stdarg = stdarg;
4234 /* If the reg that the virtual arg pointer will be translated into is
4235 not a fixed reg or is the stack pointer, make a copy of the virtual
4236 arg pointer, and address parms via the copy. The frame pointer is
4237 considered fixed even though it is not marked as such.
4239 The second time through, simply use ap to avoid generating rtx. */
4241 if ((ARG_POINTER_REGNUM == STACK_POINTER_REGNUM
4242 || ! (fixed_regs[ARG_POINTER_REGNUM]
4243 || ARG_POINTER_REGNUM == FRAME_POINTER_REGNUM)))
4244 internal_arg_pointer = copy_to_reg (virtual_incoming_args_rtx);
4245 else
4246 internal_arg_pointer = virtual_incoming_args_rtx;
4247 current_function_internal_arg_pointer = internal_arg_pointer;
4249 stack_args_size.constant = 0;
4250 stack_args_size.var = 0;
4252 /* If struct value address is treated as the first argument, make it so. */
4253 if (aggregate_value_p (DECL_RESULT (fndecl))
4254 && ! current_function_returns_pcc_struct
4255 && struct_value_incoming_rtx == 0)
4257 tree type = build_pointer_type (TREE_TYPE (fntype));
4259 function_result_decl = build_decl (PARM_DECL, NULL_TREE, type);
4261 DECL_ARG_TYPE (function_result_decl) = type;
4262 TREE_CHAIN (function_result_decl) = fnargs;
4263 fnargs = function_result_decl;
4266 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
4267 parm_reg_stack_loc = (rtx *) ggc_alloc_cleared (max_parm_reg * sizeof (rtx));
4269 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
4270 INIT_CUMULATIVE_INCOMING_ARGS (args_so_far, fntype, NULL_RTX);
4271 #else
4272 INIT_CUMULATIVE_ARGS (args_so_far, fntype, NULL_RTX, 0);
4273 #endif
4275 /* We haven't yet found an argument that we must push and pretend the
4276 caller did. */
4277 current_function_pretend_args_size = 0;
4279 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
4281 struct args_size stack_offset;
4282 struct args_size arg_size;
4283 int passed_pointer = 0;
4284 int did_conversion = 0;
4285 tree passed_type = DECL_ARG_TYPE (parm);
4286 tree nominal_type = TREE_TYPE (parm);
4287 int pretend_named;
4288 int last_named = 0, named_arg;
4290 /* Set LAST_NAMED if this is last named arg before last
4291 anonymous args. */
4292 if (stdarg)
4294 tree tem;
4296 for (tem = TREE_CHAIN (parm); tem; tem = TREE_CHAIN (tem))
4297 if (DECL_NAME (tem))
4298 break;
4300 if (tem == 0)
4301 last_named = 1;
4303 /* Set NAMED_ARG if this arg should be treated as a named arg. For
4304 most machines, if this is a varargs/stdarg function, then we treat
4305 the last named arg as if it were anonymous too. */
4306 named_arg = STRICT_ARGUMENT_NAMING ? 1 : ! last_named;
4308 if (TREE_TYPE (parm) == error_mark_node
4309 /* This can happen after weird syntax errors
4310 or if an enum type is defined among the parms. */
4311 || TREE_CODE (parm) != PARM_DECL
4312 || passed_type == NULL)
4314 SET_DECL_RTL (parm, gen_rtx_MEM (BLKmode, const0_rtx));
4315 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4316 TREE_USED (parm) = 1;
4317 continue;
4320 /* Find mode of arg as it is passed, and mode of arg
4321 as it should be during execution of this function. */
4322 passed_mode = TYPE_MODE (passed_type);
4323 nominal_mode = TYPE_MODE (nominal_type);
4325 /* If the parm's mode is VOID, its value doesn't matter,
4326 and avoid the usual things like emit_move_insn that could crash. */
4327 if (nominal_mode == VOIDmode)
4329 SET_DECL_RTL (parm, const0_rtx);
4330 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
4331 continue;
4334 /* If the parm is to be passed as a transparent union, use the
4335 type of the first field for the tests below. We have already
4336 verified that the modes are the same. */
4337 if (DECL_TRANSPARENT_UNION (parm)
4338 || (TREE_CODE (passed_type) == UNION_TYPE
4339 && TYPE_TRANSPARENT_UNION (passed_type)))
4340 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
4342 /* See if this arg was passed by invisible reference. It is if
4343 it is an object whose size depends on the contents of the
4344 object itself or if the machine requires these objects be passed
4345 that way. */
4347 if ((TREE_CODE (TYPE_SIZE (passed_type)) != INTEGER_CST
4348 && contains_placeholder_p (TYPE_SIZE (passed_type)))
4349 || TREE_ADDRESSABLE (passed_type)
4350 #ifdef FUNCTION_ARG_PASS_BY_REFERENCE
4351 || FUNCTION_ARG_PASS_BY_REFERENCE (args_so_far, passed_mode,
4352 passed_type, named_arg)
4353 #endif
4356 passed_type = nominal_type = build_pointer_type (passed_type);
4357 passed_pointer = 1;
4358 passed_mode = nominal_mode = Pmode;
4360 /* See if the frontend wants to pass this by invisible reference. */
4361 else if (passed_type != nominal_type
4362 && POINTER_TYPE_P (passed_type)
4363 && TREE_TYPE (passed_type) == nominal_type)
4365 nominal_type = passed_type;
4366 passed_pointer = 1;
4367 passed_mode = nominal_mode = Pmode;
4370 promoted_mode = passed_mode;
4372 #ifdef PROMOTE_FUNCTION_ARGS
4373 /* Compute the mode in which the arg is actually extended to. */
4374 unsignedp = TREE_UNSIGNED (passed_type);
4375 promoted_mode = promote_mode (passed_type, promoted_mode, &unsignedp, 1);
4376 #endif
4378 /* Let machine desc say which reg (if any) the parm arrives in.
4379 0 means it arrives on the stack. */
4380 #ifdef FUNCTION_INCOMING_ARG
4381 entry_parm = FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4382 passed_type, named_arg);
4383 #else
4384 entry_parm = FUNCTION_ARG (args_so_far, promoted_mode,
4385 passed_type, named_arg);
4386 #endif
4388 if (entry_parm == 0)
4389 promoted_mode = passed_mode;
4391 #ifdef SETUP_INCOMING_VARARGS
4392 /* If this is the last named parameter, do any required setup for
4393 varargs or stdargs. We need to know about the case of this being an
4394 addressable type, in which case we skip the registers it
4395 would have arrived in.
4397 For stdargs, LAST_NAMED will be set for two parameters, the one that
4398 is actually the last named, and the dummy parameter. We only
4399 want to do this action once.
4401 Also, indicate when RTL generation is to be suppressed. */
4402 if (last_named && !varargs_setup)
4404 SETUP_INCOMING_VARARGS (args_so_far, promoted_mode, passed_type,
4405 current_function_pretend_args_size, 0);
4406 varargs_setup = 1;
4408 #endif
4410 /* Determine parm's home in the stack,
4411 in case it arrives in the stack or we should pretend it did.
4413 Compute the stack position and rtx where the argument arrives
4414 and its size.
4416 There is one complexity here: If this was a parameter that would
4417 have been passed in registers, but wasn't only because it is
4418 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
4419 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
4420 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of
4421 0 as it was the previous time. */
4423 pretend_named = named_arg || PRETEND_OUTGOING_VARARGS_NAMED;
4424 locate_and_pad_parm (promoted_mode, passed_type,
4425 #ifdef STACK_PARMS_IN_REG_PARM_AREA
4427 #else
4428 #ifdef FUNCTION_INCOMING_ARG
4429 FUNCTION_INCOMING_ARG (args_so_far, promoted_mode,
4430 passed_type,
4431 pretend_named) != 0,
4432 #else
4433 FUNCTION_ARG (args_so_far, promoted_mode,
4434 passed_type,
4435 pretend_named) != 0,
4436 #endif
4437 #endif
4438 fndecl, &stack_args_size, &stack_offset, &arg_size,
4439 &alignment_pad);
4442 rtx offset_rtx = ARGS_SIZE_RTX (stack_offset);
4444 if (offset_rtx == const0_rtx)
4445 stack_parm = gen_rtx_MEM (promoted_mode, internal_arg_pointer);
4446 else
4447 stack_parm = gen_rtx_MEM (promoted_mode,
4448 gen_rtx_PLUS (Pmode,
4449 internal_arg_pointer,
4450 offset_rtx));
4452 set_mem_attributes (stack_parm, parm, 1);
4455 /* If this parameter was passed both in registers and in the stack,
4456 use the copy on the stack. */
4457 if (MUST_PASS_IN_STACK (promoted_mode, passed_type))
4458 entry_parm = 0;
4460 #ifdef FUNCTION_ARG_PARTIAL_NREGS
4461 /* If this parm was passed part in regs and part in memory,
4462 pretend it arrived entirely in memory
4463 by pushing the register-part onto the stack.
4465 In the special case of a DImode or DFmode that is split,
4466 we could put it together in a pseudoreg directly,
4467 but for now that's not worth bothering with. */
4469 if (entry_parm)
4471 int nregs = FUNCTION_ARG_PARTIAL_NREGS (args_so_far, promoted_mode,
4472 passed_type, named_arg);
4474 if (nregs > 0)
4476 #if defined (REG_PARM_STACK_SPACE) && !defined (MAYBE_REG_PARM_STACK_SPACE)
4477 /* When REG_PARM_STACK_SPACE is nonzero, stack space for
4478 split parameters was allocated by our caller, so we
4479 won't be pushing it in the prolog. */
4480 if (REG_PARM_STACK_SPACE (fndecl) == 0)
4481 #endif
4482 current_function_pretend_args_size
4483 = (((nregs * UNITS_PER_WORD) + (PARM_BOUNDARY / BITS_PER_UNIT) - 1)
4484 / (PARM_BOUNDARY / BITS_PER_UNIT)
4485 * (PARM_BOUNDARY / BITS_PER_UNIT));
4487 /* Handle calls that pass values in multiple non-contiguous
4488 locations. The Irix 6 ABI has examples of this. */
4489 if (GET_CODE (entry_parm) == PARALLEL)
4490 emit_group_store (validize_mem (stack_parm), entry_parm,
4491 int_size_in_bytes (TREE_TYPE (parm)));
4493 else
4494 move_block_from_reg (REGNO (entry_parm),
4495 validize_mem (stack_parm), nregs,
4496 int_size_in_bytes (TREE_TYPE (parm)));
4498 entry_parm = stack_parm;
4501 #endif
4503 /* If we didn't decide this parm came in a register,
4504 by default it came on the stack. */
4505 if (entry_parm == 0)
4506 entry_parm = stack_parm;
4508 /* Record permanently how this parm was passed. */
4509 DECL_INCOMING_RTL (parm) = entry_parm;
4511 /* If there is actually space on the stack for this parm,
4512 count it in stack_args_size; otherwise set stack_parm to 0
4513 to indicate there is no preallocated stack slot for the parm. */
4515 if (entry_parm == stack_parm
4516 || (GET_CODE (entry_parm) == PARALLEL
4517 && XEXP (XVECEXP (entry_parm, 0, 0), 0) == NULL_RTX)
4518 #if defined (REG_PARM_STACK_SPACE) && ! defined (MAYBE_REG_PARM_STACK_SPACE)
4519 /* On some machines, even if a parm value arrives in a register
4520 there is still an (uninitialized) stack slot allocated for it.
4522 ??? When MAYBE_REG_PARM_STACK_SPACE is defined, we can't tell
4523 whether this parameter already has a stack slot allocated,
4524 because an arg block exists only if current_function_args_size
4525 is larger than some threshold, and we haven't calculated that
4526 yet. So, for now, we just assume that stack slots never exist
4527 in this case. */
4528 || REG_PARM_STACK_SPACE (fndecl) > 0
4529 #endif
4532 stack_args_size.constant += arg_size.constant;
4533 if (arg_size.var)
4534 ADD_PARM_SIZE (stack_args_size, arg_size.var);
4536 else
4537 /* No stack slot was pushed for this parm. */
4538 stack_parm = 0;
4540 /* Update info on where next arg arrives in registers. */
4542 FUNCTION_ARG_ADVANCE (args_so_far, promoted_mode,
4543 passed_type, named_arg);
4545 /* If we can't trust the parm stack slot to be aligned enough
4546 for its ultimate type, don't use that slot after entry.
4547 We'll make another stack slot, if we need one. */
4549 unsigned int thisparm_boundary
4550 = FUNCTION_ARG_BOUNDARY (promoted_mode, passed_type);
4552 if (GET_MODE_ALIGNMENT (nominal_mode) > thisparm_boundary)
4553 stack_parm = 0;
4556 /* If parm was passed in memory, and we need to convert it on entry,
4557 don't store it back in that same slot. */
4558 if (entry_parm != 0
4559 && nominal_mode != BLKmode && nominal_mode != passed_mode)
4560 stack_parm = 0;
4562 /* When an argument is passed in multiple locations, we can't
4563 make use of this information, but we can save some copying if
4564 the whole argument is passed in a single register. */
4565 if (GET_CODE (entry_parm) == PARALLEL
4566 && nominal_mode != BLKmode && passed_mode != BLKmode)
4568 int i, len = XVECLEN (entry_parm, 0);
4570 for (i = 0; i < len; i++)
4571 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
4572 && GET_CODE (XEXP (XVECEXP (entry_parm, 0, i), 0)) == REG
4573 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
4574 == passed_mode)
4575 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
4577 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
4578 DECL_INCOMING_RTL (parm) = entry_parm;
4579 break;
4583 /* ENTRY_PARM is an RTX for the parameter as it arrives,
4584 in the mode in which it arrives.
4585 STACK_PARM is an RTX for a stack slot where the parameter can live
4586 during the function (in case we want to put it there).
4587 STACK_PARM is 0 if no stack slot was pushed for it.
4589 Now output code if necessary to convert ENTRY_PARM to
4590 the type in which this function declares it,
4591 and store that result in an appropriate place,
4592 which may be a pseudo reg, may be STACK_PARM,
4593 or may be a local stack slot if STACK_PARM is 0.
4595 Set DECL_RTL to that place. */
4597 if (nominal_mode == BLKmode || GET_CODE (entry_parm) == PARALLEL)
4599 /* If a BLKmode arrives in registers, copy it to a stack slot.
4600 Handle calls that pass values in multiple non-contiguous
4601 locations. The Irix 6 ABI has examples of this. */
4602 if (GET_CODE (entry_parm) == REG
4603 || GET_CODE (entry_parm) == PARALLEL)
4605 int size_stored
4606 = CEIL_ROUND (int_size_in_bytes (TREE_TYPE (parm)),
4607 UNITS_PER_WORD);
4609 /* Note that we will be storing an integral number of words.
4610 So we have to be careful to ensure that we allocate an
4611 integral number of words. We do this below in the
4612 assign_stack_local if space was not allocated in the argument
4613 list. If it was, this will not work if PARM_BOUNDARY is not
4614 a multiple of BITS_PER_WORD. It isn't clear how to fix this
4615 if it becomes a problem. */
4617 if (stack_parm == 0)
4619 stack_parm
4620 = assign_stack_local (GET_MODE (entry_parm),
4621 size_stored, 0);
4622 set_mem_attributes (stack_parm, parm, 1);
4625 else if (PARM_BOUNDARY % BITS_PER_WORD != 0)
4626 abort ();
4628 /* Handle calls that pass values in multiple non-contiguous
4629 locations. The Irix 6 ABI has examples of this. */
4630 if (GET_CODE (entry_parm) == PARALLEL)
4631 emit_group_store (validize_mem (stack_parm), entry_parm,
4632 int_size_in_bytes (TREE_TYPE (parm)));
4633 else
4634 move_block_from_reg (REGNO (entry_parm),
4635 validize_mem (stack_parm),
4636 size_stored / UNITS_PER_WORD,
4637 int_size_in_bytes (TREE_TYPE (parm)));
4639 SET_DECL_RTL (parm, stack_parm);
4641 else if (! ((! optimize
4642 && ! DECL_REGISTER (parm))
4643 || TREE_SIDE_EFFECTS (parm)
4644 /* If -ffloat-store specified, don't put explicit
4645 float variables into registers. */
4646 || (flag_float_store
4647 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))
4648 /* Always assign pseudo to structure return or item passed
4649 by invisible reference. */
4650 || passed_pointer || parm == function_result_decl)
4652 /* Store the parm in a pseudoregister during the function, but we
4653 may need to do it in a wider mode. */
4655 rtx parmreg;
4656 unsigned int regno, regnoi = 0, regnor = 0;
4658 unsignedp = TREE_UNSIGNED (TREE_TYPE (parm));
4660 promoted_nominal_mode
4661 = promote_mode (TREE_TYPE (parm), nominal_mode, &unsignedp, 0);
4663 parmreg = gen_reg_rtx (promoted_nominal_mode);
4664 mark_user_reg (parmreg);
4666 /* If this was an item that we received a pointer to, set DECL_RTL
4667 appropriately. */
4668 if (passed_pointer)
4670 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (passed_type)),
4671 parmreg);
4672 set_mem_attributes (x, parm, 1);
4673 SET_DECL_RTL (parm, x);
4675 else
4677 SET_DECL_RTL (parm, parmreg);
4678 maybe_set_unchanging (DECL_RTL (parm), parm);
4681 /* Copy the value into the register. */
4682 if (nominal_mode != passed_mode
4683 || promoted_nominal_mode != promoted_mode)
4685 int save_tree_used;
4686 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
4687 mode, by the caller. We now have to convert it to
4688 NOMINAL_MODE, if different. However, PARMREG may be in
4689 a different mode than NOMINAL_MODE if it is being stored
4690 promoted.
4692 If ENTRY_PARM is a hard register, it might be in a register
4693 not valid for operating in its mode (e.g., an odd-numbered
4694 register for a DFmode). In that case, moves are the only
4695 thing valid, so we can't do a convert from there. This
4696 occurs when the calling sequence allow such misaligned
4697 usages.
4699 In addition, the conversion may involve a call, which could
4700 clobber parameters which haven't been copied to pseudo
4701 registers yet. Therefore, we must first copy the parm to
4702 a pseudo reg here, and save the conversion until after all
4703 parameters have been moved. */
4705 rtx tempreg = gen_reg_rtx (GET_MODE (entry_parm));
4707 emit_move_insn (tempreg, validize_mem (entry_parm));
4709 push_to_sequence (conversion_insns);
4710 tempreg = convert_to_mode (nominal_mode, tempreg, unsignedp);
4712 if (GET_CODE (tempreg) == SUBREG
4713 && GET_MODE (tempreg) == nominal_mode
4714 && GET_CODE (SUBREG_REG (tempreg)) == REG
4715 && nominal_mode == passed_mode
4716 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (entry_parm)
4717 && GET_MODE_SIZE (GET_MODE (tempreg))
4718 < GET_MODE_SIZE (GET_MODE (entry_parm)))
4720 /* The argument is already sign/zero extended, so note it
4721 into the subreg. */
4722 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
4723 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
4726 /* TREE_USED gets set erroneously during expand_assignment. */
4727 save_tree_used = TREE_USED (parm);
4728 expand_assignment (parm,
4729 make_tree (nominal_type, tempreg), 0, 0);
4730 TREE_USED (parm) = save_tree_used;
4731 conversion_insns = get_insns ();
4732 did_conversion = 1;
4733 end_sequence ();
4735 else
4736 emit_move_insn (parmreg, validize_mem (entry_parm));
4738 /* If we were passed a pointer but the actual value
4739 can safely live in a register, put it in one. */
4740 if (passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
4741 /* If by-reference argument was promoted, demote it. */
4742 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
4743 || ! ((! optimize
4744 && ! DECL_REGISTER (parm))
4745 || TREE_SIDE_EFFECTS (parm)
4746 /* If -ffloat-store specified, don't put explicit
4747 float variables into registers. */
4748 || (flag_float_store
4749 && TREE_CODE (TREE_TYPE (parm)) == REAL_TYPE))))
4751 /* We can't use nominal_mode, because it will have been set to
4752 Pmode above. We must use the actual mode of the parm. */
4753 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
4754 mark_user_reg (parmreg);
4755 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
4757 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
4758 int unsigned_p = TREE_UNSIGNED (TREE_TYPE (parm));
4759 push_to_sequence (conversion_insns);
4760 emit_move_insn (tempreg, DECL_RTL (parm));
4761 SET_DECL_RTL (parm,
4762 convert_to_mode (GET_MODE (parmreg),
4763 tempreg,
4764 unsigned_p));
4765 emit_move_insn (parmreg, DECL_RTL (parm));
4766 conversion_insns = get_insns();
4767 did_conversion = 1;
4768 end_sequence ();
4770 else
4771 emit_move_insn (parmreg, DECL_RTL (parm));
4772 SET_DECL_RTL (parm, parmreg);
4773 /* STACK_PARM is the pointer, not the parm, and PARMREG is
4774 now the parm. */
4775 stack_parm = 0;
4777 #ifdef FUNCTION_ARG_CALLEE_COPIES
4778 /* If we are passed an arg by reference and it is our responsibility
4779 to make a copy, do it now.
4780 PASSED_TYPE and PASSED mode now refer to the pointer, not the
4781 original argument, so we must recreate them in the call to
4782 FUNCTION_ARG_CALLEE_COPIES. */
4783 /* ??? Later add code to handle the case that if the argument isn't
4784 modified, don't do the copy. */
4786 else if (passed_pointer
4787 && FUNCTION_ARG_CALLEE_COPIES (args_so_far,
4788 TYPE_MODE (DECL_ARG_TYPE (parm)),
4789 DECL_ARG_TYPE (parm),
4790 named_arg)
4791 && ! TREE_ADDRESSABLE (DECL_ARG_TYPE (parm)))
4793 rtx copy;
4794 tree type = DECL_ARG_TYPE (parm);
4796 /* This sequence may involve a library call perhaps clobbering
4797 registers that haven't been copied to pseudos yet. */
4799 push_to_sequence (conversion_insns);
4801 if (!COMPLETE_TYPE_P (type)
4802 || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4803 /* This is a variable sized object. */
4804 copy = gen_rtx_MEM (BLKmode,
4805 allocate_dynamic_stack_space
4806 (expr_size (parm), NULL_RTX,
4807 TYPE_ALIGN (type)));
4808 else
4809 copy = assign_stack_temp (TYPE_MODE (type),
4810 int_size_in_bytes (type), 1);
4811 set_mem_attributes (copy, parm, 1);
4813 store_expr (parm, copy, 0);
4814 emit_move_insn (parmreg, XEXP (copy, 0));
4815 conversion_insns = get_insns ();
4816 did_conversion = 1;
4817 end_sequence ();
4819 #endif /* FUNCTION_ARG_CALLEE_COPIES */
4821 /* In any case, record the parm's desired stack location
4822 in case we later discover it must live in the stack.
4824 If it is a COMPLEX value, store the stack location for both
4825 halves. */
4827 if (GET_CODE (parmreg) == CONCAT)
4828 regno = MAX (REGNO (XEXP (parmreg, 0)), REGNO (XEXP (parmreg, 1)));
4829 else
4830 regno = REGNO (parmreg);
4832 if (regno >= max_parm_reg)
4834 rtx *new;
4835 int old_max_parm_reg = max_parm_reg;
4837 /* It's slow to expand this one register at a time,
4838 but it's also rare and we need max_parm_reg to be
4839 precisely correct. */
4840 max_parm_reg = regno + 1;
4841 new = (rtx *) ggc_realloc (parm_reg_stack_loc,
4842 max_parm_reg * sizeof (rtx));
4843 memset ((char *) (new + old_max_parm_reg), 0,
4844 (max_parm_reg - old_max_parm_reg) * sizeof (rtx));
4845 parm_reg_stack_loc = new;
4848 if (GET_CODE (parmreg) == CONCAT)
4850 enum machine_mode submode = GET_MODE (XEXP (parmreg, 0));
4852 regnor = REGNO (gen_realpart (submode, parmreg));
4853 regnoi = REGNO (gen_imagpart (submode, parmreg));
4855 if (stack_parm != 0)
4857 parm_reg_stack_loc[regnor]
4858 = gen_realpart (submode, stack_parm);
4859 parm_reg_stack_loc[regnoi]
4860 = gen_imagpart (submode, stack_parm);
4862 else
4864 parm_reg_stack_loc[regnor] = 0;
4865 parm_reg_stack_loc[regnoi] = 0;
4868 else
4869 parm_reg_stack_loc[REGNO (parmreg)] = stack_parm;
4871 /* Mark the register as eliminable if we did no conversion
4872 and it was copied from memory at a fixed offset,
4873 and the arg pointer was not copied to a pseudo-reg.
4874 If the arg pointer is a pseudo reg or the offset formed
4875 an invalid address, such memory-equivalences
4876 as we make here would screw up life analysis for it. */
4877 if (nominal_mode == passed_mode
4878 && ! did_conversion
4879 && stack_parm != 0
4880 && GET_CODE (stack_parm) == MEM
4881 && stack_offset.var == 0
4882 && reg_mentioned_p (virtual_incoming_args_rtx,
4883 XEXP (stack_parm, 0)))
4885 rtx linsn = get_last_insn ();
4886 rtx sinsn, set;
4888 /* Mark complex types separately. */
4889 if (GET_CODE (parmreg) == CONCAT)
4890 /* Scan backwards for the set of the real and
4891 imaginary parts. */
4892 for (sinsn = linsn; sinsn != 0;
4893 sinsn = prev_nonnote_insn (sinsn))
4895 set = single_set (sinsn);
4896 if (set != 0
4897 && SET_DEST (set) == regno_reg_rtx [regnoi])
4898 REG_NOTES (sinsn)
4899 = gen_rtx_EXPR_LIST (REG_EQUIV,
4900 parm_reg_stack_loc[regnoi],
4901 REG_NOTES (sinsn));
4902 else if (set != 0
4903 && SET_DEST (set) == regno_reg_rtx [regnor])
4904 REG_NOTES (sinsn)
4905 = gen_rtx_EXPR_LIST (REG_EQUIV,
4906 parm_reg_stack_loc[regnor],
4907 REG_NOTES (sinsn));
4909 else if ((set = single_set (linsn)) != 0
4910 && SET_DEST (set) == parmreg)
4911 REG_NOTES (linsn)
4912 = gen_rtx_EXPR_LIST (REG_EQUIV,
4913 stack_parm, REG_NOTES (linsn));
4916 /* For pointer data type, suggest pointer register. */
4917 if (POINTER_TYPE_P (TREE_TYPE (parm)))
4918 mark_reg_pointer (parmreg,
4919 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4921 /* If something wants our address, try to use ADDRESSOF. */
4922 if (TREE_ADDRESSABLE (parm))
4924 /* If we end up putting something into the stack,
4925 fixup_var_refs_insns will need to make a pass over
4926 all the instructions. It looks through the pending
4927 sequences -- but it can't see the ones in the
4928 CONVERSION_INSNS, if they're not on the sequence
4929 stack. So, we go back to that sequence, just so that
4930 the fixups will happen. */
4931 push_to_sequence (conversion_insns);
4932 put_var_into_stack (parm);
4933 conversion_insns = get_insns ();
4934 end_sequence ();
4937 else
4939 /* Value must be stored in the stack slot STACK_PARM
4940 during function execution. */
4942 if (promoted_mode != nominal_mode)
4944 /* Conversion is required. */
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 entry_parm = convert_to_mode (nominal_mode, tempreg,
4951 TREE_UNSIGNED (TREE_TYPE (parm)));
4952 if (stack_parm)
4953 /* ??? This may need a big-endian conversion on sparc64. */
4954 stack_parm = adjust_address (stack_parm, nominal_mode, 0);
4956 conversion_insns = get_insns ();
4957 did_conversion = 1;
4958 end_sequence ();
4961 if (entry_parm != stack_parm)
4963 if (stack_parm == 0)
4965 stack_parm
4966 = assign_stack_local (GET_MODE (entry_parm),
4967 GET_MODE_SIZE (GET_MODE (entry_parm)), 0);
4968 set_mem_attributes (stack_parm, parm, 1);
4971 if (promoted_mode != nominal_mode)
4973 push_to_sequence (conversion_insns);
4974 emit_move_insn (validize_mem (stack_parm),
4975 validize_mem (entry_parm));
4976 conversion_insns = get_insns ();
4977 end_sequence ();
4979 else
4980 emit_move_insn (validize_mem (stack_parm),
4981 validize_mem (entry_parm));
4984 SET_DECL_RTL (parm, stack_parm);
4987 /* If this "parameter" was the place where we are receiving the
4988 function's incoming structure pointer, set up the result. */
4989 if (parm == function_result_decl)
4991 tree result = DECL_RESULT (fndecl);
4992 rtx addr = DECL_RTL (parm);
4993 rtx x;
4995 #ifdef POINTERS_EXTEND_UNSIGNED
4996 if (GET_MODE (addr) != Pmode)
4997 addr = convert_memory_address (Pmode, addr);
4998 #endif
5000 x = gen_rtx_MEM (DECL_MODE (result), addr);
5001 set_mem_attributes (x, result, 1);
5002 SET_DECL_RTL (result, x);
5006 /* Output all parameter conversion instructions (possibly including calls)
5007 now that all parameters have been copied out of hard registers. */
5008 emit_insn (conversion_insns);
5010 last_parm_insn = get_last_insn ();
5012 current_function_args_size = stack_args_size.constant;
5014 /* Adjust function incoming argument size for alignment and
5015 minimum length. */
5017 #ifdef REG_PARM_STACK_SPACE
5018 #ifndef MAYBE_REG_PARM_STACK_SPACE
5019 current_function_args_size = MAX (current_function_args_size,
5020 REG_PARM_STACK_SPACE (fndecl));
5021 #endif
5022 #endif
5024 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
5026 current_function_args_size
5027 = ((current_function_args_size + STACK_BYTES - 1)
5028 / STACK_BYTES) * STACK_BYTES;
5030 #ifdef ARGS_GROW_DOWNWARD
5031 current_function_arg_offset_rtx
5032 = (stack_args_size.var == 0 ? GEN_INT (-stack_args_size.constant)
5033 : expand_expr (size_diffop (stack_args_size.var,
5034 size_int (-stack_args_size.constant)),
5035 NULL_RTX, VOIDmode, 0));
5036 #else
5037 current_function_arg_offset_rtx = ARGS_SIZE_RTX (stack_args_size);
5038 #endif
5040 /* See how many bytes, if any, of its args a function should try to pop
5041 on return. */
5043 current_function_pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
5044 current_function_args_size);
5046 /* For stdarg.h function, save info about
5047 regs and stack space used by the named args. */
5049 current_function_args_info = args_so_far;
5051 /* Set the rtx used for the function return value. Put this in its
5052 own variable so any optimizers that need this information don't have
5053 to include tree.h. Do this here so it gets done when an inlined
5054 function gets output. */
5056 current_function_return_rtx
5057 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
5058 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
5060 /* If scalar return value was computed in a pseudo-reg, or was a named
5061 return value that got dumped to the stack, copy that to the hard
5062 return register. */
5063 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
5065 tree decl_result = DECL_RESULT (fndecl);
5066 rtx decl_rtl = DECL_RTL (decl_result);
5068 if (REG_P (decl_rtl)
5069 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5070 : DECL_REGISTER (decl_result))
5072 rtx real_decl_rtl;
5074 #ifdef FUNCTION_OUTGOING_VALUE
5075 real_decl_rtl = FUNCTION_OUTGOING_VALUE (TREE_TYPE (decl_result),
5076 fndecl);
5077 #else
5078 real_decl_rtl = FUNCTION_VALUE (TREE_TYPE (decl_result),
5079 fndecl);
5080 #endif
5081 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
5082 /* The delay slot scheduler assumes that current_function_return_rtx
5083 holds the hard register containing the return value, not a
5084 temporary pseudo. */
5085 current_function_return_rtx = real_decl_rtl;
5090 /* Indicate whether REGNO is an incoming argument to the current function
5091 that was promoted to a wider mode. If so, return the RTX for the
5092 register (to get its mode). PMODE and PUNSIGNEDP are set to the mode
5093 that REGNO is promoted from and whether the promotion was signed or
5094 unsigned. */
5096 #ifdef PROMOTE_FUNCTION_ARGS
5099 promoted_input_arg (regno, pmode, punsignedp)
5100 unsigned int regno;
5101 enum machine_mode *pmode;
5102 int *punsignedp;
5104 tree arg;
5106 for (arg = DECL_ARGUMENTS (current_function_decl); arg;
5107 arg = TREE_CHAIN (arg))
5108 if (GET_CODE (DECL_INCOMING_RTL (arg)) == REG
5109 && REGNO (DECL_INCOMING_RTL (arg)) == regno
5110 && TYPE_MODE (DECL_ARG_TYPE (arg)) == TYPE_MODE (TREE_TYPE (arg)))
5112 enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
5113 int unsignedp = TREE_UNSIGNED (TREE_TYPE (arg));
5115 mode = promote_mode (TREE_TYPE (arg), mode, &unsignedp, 1);
5116 if (mode == GET_MODE (DECL_INCOMING_RTL (arg))
5117 && mode != DECL_MODE (arg))
5119 *pmode = DECL_MODE (arg);
5120 *punsignedp = unsignedp;
5121 return DECL_INCOMING_RTL (arg);
5125 return 0;
5128 #endif
5130 /* Compute the size and offset from the start of the stacked arguments for a
5131 parm passed in mode PASSED_MODE and with type TYPE.
5133 INITIAL_OFFSET_PTR points to the current offset into the stacked
5134 arguments.
5136 The starting offset and size for this parm are returned in *OFFSET_PTR
5137 and *ARG_SIZE_PTR, respectively.
5139 IN_REGS is nonzero if the argument will be passed in registers. It will
5140 never be set if REG_PARM_STACK_SPACE is not defined.
5142 FNDECL is the function in which the argument was defined.
5144 There are two types of rounding that are done. The first, controlled by
5145 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
5146 list to be aligned to the specific boundary (in bits). This rounding
5147 affects the initial and starting offsets, but not the argument size.
5149 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
5150 optionally rounds the size of the parm to PARM_BOUNDARY. The
5151 initial offset is not affected by this rounding, while the size always
5152 is and the starting offset may be. */
5154 /* offset_ptr will be negative for ARGS_GROW_DOWNWARD case;
5155 initial_offset_ptr is positive because locate_and_pad_parm's
5156 callers pass in the total size of args so far as
5157 initial_offset_ptr. arg_size_ptr is always positive. */
5159 void
5160 locate_and_pad_parm (passed_mode, type, in_regs, fndecl,
5161 initial_offset_ptr, offset_ptr, arg_size_ptr,
5162 alignment_pad)
5163 enum machine_mode passed_mode;
5164 tree type;
5165 int in_regs ATTRIBUTE_UNUSED;
5166 tree fndecl ATTRIBUTE_UNUSED;
5167 struct args_size *initial_offset_ptr;
5168 struct args_size *offset_ptr;
5169 struct args_size *arg_size_ptr;
5170 struct args_size *alignment_pad;
5173 tree sizetree
5174 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
5175 enum direction where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
5176 int boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
5177 #ifdef ARGS_GROW_DOWNWARD
5178 tree s2 = sizetree;
5179 #endif
5181 #ifdef REG_PARM_STACK_SPACE
5182 /* If we have found a stack parm before we reach the end of the
5183 area reserved for registers, skip that area. */
5184 if (! in_regs)
5186 int reg_parm_stack_space = 0;
5188 #ifdef MAYBE_REG_PARM_STACK_SPACE
5189 reg_parm_stack_space = MAYBE_REG_PARM_STACK_SPACE;
5190 #else
5191 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
5192 #endif
5193 if (reg_parm_stack_space > 0)
5195 if (initial_offset_ptr->var)
5197 initial_offset_ptr->var
5198 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
5199 ssize_int (reg_parm_stack_space));
5200 initial_offset_ptr->constant = 0;
5202 else if (initial_offset_ptr->constant < reg_parm_stack_space)
5203 initial_offset_ptr->constant = reg_parm_stack_space;
5206 #endif /* REG_PARM_STACK_SPACE */
5208 arg_size_ptr->var = 0;
5209 arg_size_ptr->constant = 0;
5210 alignment_pad->var = 0;
5211 alignment_pad->constant = 0;
5213 #ifdef ARGS_GROW_DOWNWARD
5214 if (initial_offset_ptr->var)
5216 offset_ptr->constant = 0;
5217 offset_ptr->var = size_binop (MINUS_EXPR, ssize_int (0),
5218 initial_offset_ptr->var);
5220 else
5222 offset_ptr->constant = -initial_offset_ptr->constant;
5223 offset_ptr->var = 0;
5226 if (where_pad != none
5227 && (!host_integerp (sizetree, 1)
5228 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5229 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
5230 SUB_PARM_SIZE (*offset_ptr, s2);
5232 if (!in_regs
5233 #ifdef REG_PARM_STACK_SPACE
5234 || REG_PARM_STACK_SPACE (fndecl) > 0
5235 #endif
5237 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad);
5239 if (initial_offset_ptr->var)
5240 arg_size_ptr->var = size_binop (MINUS_EXPR,
5241 size_binop (MINUS_EXPR,
5242 ssize_int (0),
5243 initial_offset_ptr->var),
5244 offset_ptr->var);
5246 else
5247 arg_size_ptr->constant = (-initial_offset_ptr->constant
5248 - offset_ptr->constant);
5250 /* Pad_below needs the pre-rounded size to know how much to pad below.
5251 We only pad parameters which are not in registers as they have their
5252 padding done elsewhere. */
5253 if (where_pad == downward
5254 && !in_regs)
5255 pad_below (offset_ptr, passed_mode, sizetree);
5257 #else /* !ARGS_GROW_DOWNWARD */
5258 if (!in_regs
5259 #ifdef REG_PARM_STACK_SPACE
5260 || REG_PARM_STACK_SPACE (fndecl) > 0
5261 #endif
5263 pad_to_arg_alignment (initial_offset_ptr, boundary, alignment_pad);
5264 *offset_ptr = *initial_offset_ptr;
5266 #ifdef PUSH_ROUNDING
5267 if (passed_mode != BLKmode)
5268 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
5269 #endif
5271 /* Pad_below needs the pre-rounded size to know how much to pad below
5272 so this must be done before rounding up. */
5273 if (where_pad == downward
5274 /* However, BLKmode args passed in regs have their padding done elsewhere.
5275 The stack slot must be able to hold the entire register. */
5276 && !(in_regs && passed_mode == BLKmode))
5277 pad_below (offset_ptr, passed_mode, sizetree);
5279 if (where_pad != none
5280 && (!host_integerp (sizetree, 1)
5281 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
5282 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5284 ADD_PARM_SIZE (*arg_size_ptr, sizetree);
5285 #endif /* ARGS_GROW_DOWNWARD */
5288 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
5289 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
5291 static void
5292 pad_to_arg_alignment (offset_ptr, boundary, alignment_pad)
5293 struct args_size *offset_ptr;
5294 int boundary;
5295 struct args_size *alignment_pad;
5297 tree save_var = NULL_TREE;
5298 HOST_WIDE_INT save_constant = 0;
5300 int boundary_in_bytes = boundary / BITS_PER_UNIT;
5302 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5304 save_var = offset_ptr->var;
5305 save_constant = offset_ptr->constant;
5308 alignment_pad->var = NULL_TREE;
5309 alignment_pad->constant = 0;
5311 if (boundary > BITS_PER_UNIT)
5313 if (offset_ptr->var)
5315 offset_ptr->var =
5316 #ifdef ARGS_GROW_DOWNWARD
5317 round_down
5318 #else
5319 round_up
5320 #endif
5321 (ARGS_SIZE_TREE (*offset_ptr),
5322 boundary / BITS_PER_UNIT);
5323 offset_ptr->constant = 0; /*?*/
5324 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5325 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
5326 save_var);
5328 else
5330 offset_ptr->constant =
5331 #ifdef ARGS_GROW_DOWNWARD
5332 FLOOR_ROUND (offset_ptr->constant, boundary_in_bytes);
5333 #else
5334 CEIL_ROUND (offset_ptr->constant, boundary_in_bytes);
5335 #endif
5336 if (boundary > PARM_BOUNDARY && boundary > STACK_BOUNDARY)
5337 alignment_pad->constant = offset_ptr->constant - save_constant;
5342 static void
5343 pad_below (offset_ptr, passed_mode, sizetree)
5344 struct args_size *offset_ptr;
5345 enum machine_mode passed_mode;
5346 tree sizetree;
5348 if (passed_mode != BLKmode)
5350 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
5351 offset_ptr->constant
5352 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
5353 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
5354 - GET_MODE_SIZE (passed_mode));
5356 else
5358 if (TREE_CODE (sizetree) != INTEGER_CST
5359 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
5361 /* Round the size up to multiple of PARM_BOUNDARY bits. */
5362 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
5363 /* Add it in. */
5364 ADD_PARM_SIZE (*offset_ptr, s2);
5365 SUB_PARM_SIZE (*offset_ptr, sizetree);
5370 /* Walk the tree of blocks describing the binding levels within a function
5371 and warn about uninitialized variables.
5372 This is done after calling flow_analysis and before global_alloc
5373 clobbers the pseudo-regs to hard regs. */
5375 void
5376 uninitialized_vars_warning (block)
5377 tree block;
5379 tree decl, sub;
5380 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5382 if (warn_uninitialized
5383 && TREE_CODE (decl) == VAR_DECL
5384 /* These warnings are unreliable for and aggregates
5385 because assigning the fields one by one can fail to convince
5386 flow.c that the entire aggregate was initialized.
5387 Unions are troublesome because members may be shorter. */
5388 && ! AGGREGATE_TYPE_P (TREE_TYPE (decl))
5389 && DECL_RTL (decl) != 0
5390 && GET_CODE (DECL_RTL (decl)) == REG
5391 /* Global optimizations can make it difficult to determine if a
5392 particular variable has been initialized. However, a VAR_DECL
5393 with a nonzero DECL_INITIAL had an initializer, so do not
5394 claim it is potentially uninitialized.
5396 We do not care about the actual value in DECL_INITIAL, so we do
5397 not worry that it may be a dangling pointer. */
5398 && DECL_INITIAL (decl) == NULL_TREE
5399 && regno_uninitialized (REGNO (DECL_RTL (decl))))
5400 warning_with_decl (decl,
5401 "`%s' might be used uninitialized in this function");
5402 if (extra_warnings
5403 && TREE_CODE (decl) == VAR_DECL
5404 && DECL_RTL (decl) != 0
5405 && GET_CODE (DECL_RTL (decl)) == REG
5406 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5407 warning_with_decl (decl,
5408 "variable `%s' might be clobbered by `longjmp' or `vfork'");
5410 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5411 uninitialized_vars_warning (sub);
5414 /* Do the appropriate part of uninitialized_vars_warning
5415 but for arguments instead of local variables. */
5417 void
5418 setjmp_args_warning ()
5420 tree decl;
5421 for (decl = DECL_ARGUMENTS (current_function_decl);
5422 decl; decl = TREE_CHAIN (decl))
5423 if (DECL_RTL (decl) != 0
5424 && GET_CODE (DECL_RTL (decl)) == REG
5425 && regno_clobbered_at_setjmp (REGNO (DECL_RTL (decl))))
5426 warning_with_decl (decl,
5427 "argument `%s' might be clobbered by `longjmp' or `vfork'");
5430 /* If this function call setjmp, put all vars into the stack
5431 unless they were declared `register'. */
5433 void
5434 setjmp_protect (block)
5435 tree block;
5437 tree decl, sub;
5438 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
5439 if ((TREE_CODE (decl) == VAR_DECL
5440 || TREE_CODE (decl) == PARM_DECL)
5441 && DECL_RTL (decl) != 0
5442 && (GET_CODE (DECL_RTL (decl)) == REG
5443 || (GET_CODE (DECL_RTL (decl)) == MEM
5444 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5445 /* If this variable came from an inline function, it must be
5446 that its life doesn't overlap the setjmp. If there was a
5447 setjmp in the function, it would already be in memory. We
5448 must exclude such variable because their DECL_RTL might be
5449 set to strange things such as virtual_stack_vars_rtx. */
5450 && ! DECL_FROM_INLINE (decl)
5451 && (
5452 #ifdef NON_SAVING_SETJMP
5453 /* If longjmp doesn't restore the registers,
5454 don't put anything in them. */
5455 NON_SAVING_SETJMP
5457 #endif
5458 ! DECL_REGISTER (decl)))
5459 put_var_into_stack (decl);
5460 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = TREE_CHAIN (sub))
5461 setjmp_protect (sub);
5464 /* Like the previous function, but for args instead of local variables. */
5466 void
5467 setjmp_protect_args ()
5469 tree decl;
5470 for (decl = DECL_ARGUMENTS (current_function_decl);
5471 decl; decl = TREE_CHAIN (decl))
5472 if ((TREE_CODE (decl) == VAR_DECL
5473 || TREE_CODE (decl) == PARM_DECL)
5474 && DECL_RTL (decl) != 0
5475 && (GET_CODE (DECL_RTL (decl)) == REG
5476 || (GET_CODE (DECL_RTL (decl)) == MEM
5477 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == ADDRESSOF))
5478 && (
5479 /* If longjmp doesn't restore the registers,
5480 don't put anything in them. */
5481 #ifdef NON_SAVING_SETJMP
5482 NON_SAVING_SETJMP
5484 #endif
5485 ! DECL_REGISTER (decl)))
5486 put_var_into_stack (decl);
5489 /* Return the context-pointer register corresponding to DECL,
5490 or 0 if it does not need one. */
5493 lookup_static_chain (decl)
5494 tree decl;
5496 tree context = decl_function_context (decl);
5497 tree link;
5499 if (context == 0
5500 || (TREE_CODE (decl) == FUNCTION_DECL && DECL_NO_STATIC_CHAIN (decl)))
5501 return 0;
5503 /* We treat inline_function_decl as an alias for the current function
5504 because that is the inline function whose vars, types, etc.
5505 are being merged into the current function.
5506 See expand_inline_function. */
5507 if (context == current_function_decl || context == inline_function_decl)
5508 return virtual_stack_vars_rtx;
5510 for (link = context_display; link; link = TREE_CHAIN (link))
5511 if (TREE_PURPOSE (link) == context)
5512 return RTL_EXPR_RTL (TREE_VALUE (link));
5514 abort ();
5517 /* Convert a stack slot address ADDR for variable VAR
5518 (from a containing function)
5519 into an address valid in this function (using a static chain). */
5522 fix_lexical_addr (addr, var)
5523 rtx addr;
5524 tree var;
5526 rtx basereg;
5527 HOST_WIDE_INT displacement;
5528 tree context = decl_function_context (var);
5529 struct function *fp;
5530 rtx base = 0;
5532 /* If this is the present function, we need not do anything. */
5533 if (context == current_function_decl || context == inline_function_decl)
5534 return addr;
5536 fp = find_function_data (context);
5538 if (GET_CODE (addr) == ADDRESSOF && GET_CODE (XEXP (addr, 0)) == MEM)
5539 addr = XEXP (XEXP (addr, 0), 0);
5541 /* Decode given address as base reg plus displacement. */
5542 if (GET_CODE (addr) == REG)
5543 basereg = addr, displacement = 0;
5544 else if (GET_CODE (addr) == PLUS && GET_CODE (XEXP (addr, 1)) == CONST_INT)
5545 basereg = XEXP (addr, 0), displacement = INTVAL (XEXP (addr, 1));
5546 else
5547 abort ();
5549 /* We accept vars reached via the containing function's
5550 incoming arg pointer and via its stack variables pointer. */
5551 if (basereg == fp->internal_arg_pointer)
5553 /* If reached via arg pointer, get the arg pointer value
5554 out of that function's stack frame.
5556 There are two cases: If a separate ap is needed, allocate a
5557 slot in the outer function for it and dereference it that way.
5558 This is correct even if the real ap is actually a pseudo.
5559 Otherwise, just adjust the offset from the frame pointer to
5560 compensate. */
5562 #ifdef NEED_SEPARATE_AP
5563 rtx addr;
5565 addr = get_arg_pointer_save_area (fp);
5566 addr = fix_lexical_addr (XEXP (addr, 0), var);
5567 addr = memory_address (Pmode, addr);
5569 base = gen_rtx_MEM (Pmode, addr);
5570 set_mem_alias_set (base, get_frame_alias_set ());
5571 base = copy_to_reg (base);
5572 #else
5573 displacement += (FIRST_PARM_OFFSET (context) - STARTING_FRAME_OFFSET);
5574 base = lookup_static_chain (var);
5575 #endif
5578 else if (basereg == virtual_stack_vars_rtx)
5580 /* This is the same code as lookup_static_chain, duplicated here to
5581 avoid an extra call to decl_function_context. */
5582 tree link;
5584 for (link = context_display; link; link = TREE_CHAIN (link))
5585 if (TREE_PURPOSE (link) == context)
5587 base = RTL_EXPR_RTL (TREE_VALUE (link));
5588 break;
5592 if (base == 0)
5593 abort ();
5595 /* Use same offset, relative to appropriate static chain or argument
5596 pointer. */
5597 return plus_constant (base, displacement);
5600 /* Return the address of the trampoline for entering nested fn FUNCTION.
5601 If necessary, allocate a trampoline (in the stack frame)
5602 and emit rtl to initialize its contents (at entry to this function). */
5605 trampoline_address (function)
5606 tree function;
5608 tree link;
5609 tree rtlexp;
5610 rtx tramp;
5611 struct function *fp;
5612 tree fn_context;
5614 /* Find an existing trampoline and return it. */
5615 for (link = trampoline_list; link; link = TREE_CHAIN (link))
5616 if (TREE_PURPOSE (link) == function)
5617 return
5618 adjust_trampoline_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0));
5620 for (fp = outer_function_chain; fp; fp = fp->outer)
5621 for (link = fp->x_trampoline_list; link; link = TREE_CHAIN (link))
5622 if (TREE_PURPOSE (link) == function)
5624 tramp = fix_lexical_addr (XEXP (RTL_EXPR_RTL (TREE_VALUE (link)), 0),
5625 function);
5626 return adjust_trampoline_addr (tramp);
5629 /* None exists; we must make one. */
5631 /* Find the `struct function' for the function containing FUNCTION. */
5632 fp = 0;
5633 fn_context = decl_function_context (function);
5634 if (fn_context != current_function_decl
5635 && fn_context != inline_function_decl)
5636 fp = find_function_data (fn_context);
5638 /* Allocate run-time space for this trampoline
5639 (usually in the defining function's stack frame). */
5640 #ifdef ALLOCATE_TRAMPOLINE
5641 tramp = ALLOCATE_TRAMPOLINE (fp);
5642 #else
5643 /* If rounding needed, allocate extra space
5644 to ensure we have TRAMPOLINE_SIZE bytes left after rounding up. */
5645 #define TRAMPOLINE_REAL_SIZE \
5646 (TRAMPOLINE_SIZE + (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT) - 1)
5647 tramp = assign_stack_local_1 (BLKmode, TRAMPOLINE_REAL_SIZE, 0,
5648 fp ? fp : cfun);
5649 #endif
5651 /* Record the trampoline for reuse and note it for later initialization
5652 by expand_function_end. */
5653 if (fp != 0)
5655 rtlexp = make_node (RTL_EXPR);
5656 RTL_EXPR_RTL (rtlexp) = tramp;
5657 fp->x_trampoline_list = tree_cons (function, rtlexp,
5658 fp->x_trampoline_list);
5660 else
5662 /* Make the RTL_EXPR node temporary, not momentary, so that the
5663 trampoline_list doesn't become garbage. */
5664 rtlexp = make_node (RTL_EXPR);
5666 RTL_EXPR_RTL (rtlexp) = tramp;
5667 trampoline_list = tree_cons (function, rtlexp, trampoline_list);
5670 tramp = fix_lexical_addr (XEXP (tramp, 0), function);
5671 return adjust_trampoline_addr (tramp);
5674 /* Given a trampoline address,
5675 round it to multiple of TRAMPOLINE_ALIGNMENT. */
5677 static rtx
5678 round_trampoline_addr (tramp)
5679 rtx tramp;
5681 /* Round address up to desired boundary. */
5682 rtx temp = gen_reg_rtx (Pmode);
5683 rtx addend = GEN_INT (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT - 1);
5684 rtx mask = GEN_INT (-TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
5686 temp = expand_simple_binop (Pmode, PLUS, tramp, addend,
5687 temp, 0, OPTAB_LIB_WIDEN);
5688 tramp = expand_simple_binop (Pmode, AND, temp, mask,
5689 temp, 0, OPTAB_LIB_WIDEN);
5691 return tramp;
5694 /* Given a trampoline address, round it then apply any
5695 platform-specific adjustments so that the result can be used for a
5696 function call . */
5698 static rtx
5699 adjust_trampoline_addr (tramp)
5700 rtx tramp;
5702 tramp = round_trampoline_addr (tramp);
5703 #ifdef TRAMPOLINE_ADJUST_ADDRESS
5704 TRAMPOLINE_ADJUST_ADDRESS (tramp);
5705 #endif
5706 return tramp;
5709 /* Put all this function's BLOCK nodes including those that are chained
5710 onto the first block into a vector, and return it.
5711 Also store in each NOTE for the beginning or end of a block
5712 the index of that block in the vector.
5713 The arguments are BLOCK, the chain of top-level blocks of the function,
5714 and INSNS, the insn chain of the function. */
5716 void
5717 identify_blocks ()
5719 int n_blocks;
5720 tree *block_vector, *last_block_vector;
5721 tree *block_stack;
5722 tree block = DECL_INITIAL (current_function_decl);
5724 if (block == 0)
5725 return;
5727 /* Fill the BLOCK_VECTOR with all of the BLOCKs in this function, in
5728 depth-first order. */
5729 block_vector = get_block_vector (block, &n_blocks);
5730 block_stack = (tree *) xmalloc (n_blocks * sizeof (tree));
5732 last_block_vector = identify_blocks_1 (get_insns (),
5733 block_vector + 1,
5734 block_vector + n_blocks,
5735 block_stack);
5737 /* If we didn't use all of the subblocks, we've misplaced block notes. */
5738 /* ??? This appears to happen all the time. Latent bugs elsewhere? */
5739 if (0 && last_block_vector != block_vector + n_blocks)
5740 abort ();
5742 free (block_vector);
5743 free (block_stack);
5746 /* Subroutine of identify_blocks. Do the block substitution on the
5747 insn chain beginning with INSNS. Recurse for CALL_PLACEHOLDER chains.
5749 BLOCK_STACK is pushed and popped for each BLOCK_BEGIN/BLOCK_END pair.
5750 BLOCK_VECTOR is incremented for each block seen. */
5752 static tree *
5753 identify_blocks_1 (insns, block_vector, end_block_vector, orig_block_stack)
5754 rtx insns;
5755 tree *block_vector;
5756 tree *end_block_vector;
5757 tree *orig_block_stack;
5759 rtx insn;
5760 tree *block_stack = orig_block_stack;
5762 for (insn = insns; insn; insn = NEXT_INSN (insn))
5764 if (GET_CODE (insn) == NOTE)
5766 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5768 tree b;
5770 /* If there are more block notes than BLOCKs, something
5771 is badly wrong. */
5772 if (block_vector == end_block_vector)
5773 abort ();
5775 b = *block_vector++;
5776 NOTE_BLOCK (insn) = b;
5777 *block_stack++ = b;
5779 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5781 /* If there are more NOTE_INSN_BLOCK_ENDs than
5782 NOTE_INSN_BLOCK_BEGs, something is badly wrong. */
5783 if (block_stack == orig_block_stack)
5784 abort ();
5786 NOTE_BLOCK (insn) = *--block_stack;
5789 else if (GET_CODE (insn) == CALL_INSN
5790 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5792 rtx cp = PATTERN (insn);
5794 block_vector = identify_blocks_1 (XEXP (cp, 0), block_vector,
5795 end_block_vector, block_stack);
5796 if (XEXP (cp, 1))
5797 block_vector = identify_blocks_1 (XEXP (cp, 1), block_vector,
5798 end_block_vector, block_stack);
5799 if (XEXP (cp, 2))
5800 block_vector = identify_blocks_1 (XEXP (cp, 2), block_vector,
5801 end_block_vector, block_stack);
5805 /* If there are more NOTE_INSN_BLOCK_BEGINs than NOTE_INSN_BLOCK_ENDs,
5806 something is badly wrong. */
5807 if (block_stack != orig_block_stack)
5808 abort ();
5810 return block_vector;
5813 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
5814 and create duplicate blocks. */
5815 /* ??? Need an option to either create block fragments or to create
5816 abstract origin duplicates of a source block. It really depends
5817 on what optimization has been performed. */
5819 void
5820 reorder_blocks ()
5822 tree block = DECL_INITIAL (current_function_decl);
5823 varray_type block_stack;
5825 if (block == NULL_TREE)
5826 return;
5828 VARRAY_TREE_INIT (block_stack, 10, "block_stack");
5830 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
5831 reorder_blocks_0 (block);
5833 /* Prune the old trees away, so that they don't get in the way. */
5834 BLOCK_SUBBLOCKS (block) = NULL_TREE;
5835 BLOCK_CHAIN (block) = NULL_TREE;
5837 /* Recreate the block tree from the note nesting. */
5838 reorder_blocks_1 (get_insns (), block, &block_stack);
5839 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
5841 /* Remove deleted blocks from the block fragment chains. */
5842 reorder_fix_fragments (block);
5845 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
5847 static void
5848 reorder_blocks_0 (block)
5849 tree block;
5851 while (block)
5853 TREE_ASM_WRITTEN (block) = 0;
5854 reorder_blocks_0 (BLOCK_SUBBLOCKS (block));
5855 block = BLOCK_CHAIN (block);
5859 static void
5860 reorder_blocks_1 (insns, current_block, p_block_stack)
5861 rtx insns;
5862 tree current_block;
5863 varray_type *p_block_stack;
5865 rtx insn;
5867 for (insn = insns; insn; insn = NEXT_INSN (insn))
5869 if (GET_CODE (insn) == NOTE)
5871 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG)
5873 tree block = NOTE_BLOCK (insn);
5875 /* If we have seen this block before, that means it now
5876 spans multiple address regions. Create a new fragment. */
5877 if (TREE_ASM_WRITTEN (block))
5879 tree new_block = copy_node (block);
5880 tree origin;
5882 origin = (BLOCK_FRAGMENT_ORIGIN (block)
5883 ? BLOCK_FRAGMENT_ORIGIN (block)
5884 : block);
5885 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
5886 BLOCK_FRAGMENT_CHAIN (new_block)
5887 = BLOCK_FRAGMENT_CHAIN (origin);
5888 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
5890 NOTE_BLOCK (insn) = new_block;
5891 block = new_block;
5894 BLOCK_SUBBLOCKS (block) = 0;
5895 TREE_ASM_WRITTEN (block) = 1;
5896 BLOCK_SUPERCONTEXT (block) = current_block;
5897 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
5898 BLOCK_SUBBLOCKS (current_block) = block;
5899 current_block = block;
5900 VARRAY_PUSH_TREE (*p_block_stack, block);
5902 else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)
5904 NOTE_BLOCK (insn) = VARRAY_TOP_TREE (*p_block_stack);
5905 VARRAY_POP (*p_block_stack);
5906 BLOCK_SUBBLOCKS (current_block)
5907 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
5908 current_block = BLOCK_SUPERCONTEXT (current_block);
5911 else if (GET_CODE (insn) == CALL_INSN
5912 && GET_CODE (PATTERN (insn)) == CALL_PLACEHOLDER)
5914 rtx cp = PATTERN (insn);
5915 reorder_blocks_1 (XEXP (cp, 0), current_block, p_block_stack);
5916 if (XEXP (cp, 1))
5917 reorder_blocks_1 (XEXP (cp, 1), current_block, p_block_stack);
5918 if (XEXP (cp, 2))
5919 reorder_blocks_1 (XEXP (cp, 2), current_block, p_block_stack);
5924 /* Rationalize BLOCK_FRAGMENT_ORIGIN. If an origin block no longer
5925 appears in the block tree, select one of the fragments to become
5926 the new origin block. */
5928 static void
5929 reorder_fix_fragments (block)
5930 tree block;
5932 while (block)
5934 tree dup_origin = BLOCK_FRAGMENT_ORIGIN (block);
5935 tree new_origin = NULL_TREE;
5937 if (dup_origin)
5939 if (! TREE_ASM_WRITTEN (dup_origin))
5941 new_origin = BLOCK_FRAGMENT_CHAIN (dup_origin);
5943 /* Find the first of the remaining fragments. There must
5944 be at least one -- the current block. */
5945 while (! TREE_ASM_WRITTEN (new_origin))
5946 new_origin = BLOCK_FRAGMENT_CHAIN (new_origin);
5947 BLOCK_FRAGMENT_ORIGIN (new_origin) = NULL_TREE;
5950 else if (! dup_origin)
5951 new_origin = block;
5953 /* Re-root the rest of the fragments to the new origin. In the
5954 case that DUP_ORIGIN was null, that means BLOCK was the origin
5955 of a chain of fragments and we want to remove those fragments
5956 that didn't make it to the output. */
5957 if (new_origin)
5959 tree *pp = &BLOCK_FRAGMENT_CHAIN (new_origin);
5960 tree chain = *pp;
5962 while (chain)
5964 if (TREE_ASM_WRITTEN (chain))
5966 BLOCK_FRAGMENT_ORIGIN (chain) = new_origin;
5967 *pp = chain;
5968 pp = &BLOCK_FRAGMENT_CHAIN (chain);
5970 chain = BLOCK_FRAGMENT_CHAIN (chain);
5972 *pp = NULL_TREE;
5975 reorder_fix_fragments (BLOCK_SUBBLOCKS (block));
5976 block = BLOCK_CHAIN (block);
5980 /* Reverse the order of elements in the chain T of blocks,
5981 and return the new head of the chain (old last element). */
5983 static tree
5984 blocks_nreverse (t)
5985 tree t;
5987 tree prev = 0, decl, next;
5988 for (decl = t; decl; decl = next)
5990 next = BLOCK_CHAIN (decl);
5991 BLOCK_CHAIN (decl) = prev;
5992 prev = decl;
5994 return prev;
5997 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
5998 non-NULL, list them all into VECTOR, in a depth-first preorder
5999 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
6000 blocks. */
6002 static int
6003 all_blocks (block, vector)
6004 tree block;
6005 tree *vector;
6007 int n_blocks = 0;
6009 while (block)
6011 TREE_ASM_WRITTEN (block) = 0;
6013 /* Record this block. */
6014 if (vector)
6015 vector[n_blocks] = block;
6017 ++n_blocks;
6019 /* Record the subblocks, and their subblocks... */
6020 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
6021 vector ? vector + n_blocks : 0);
6022 block = BLOCK_CHAIN (block);
6025 return n_blocks;
6028 /* Return a vector containing all the blocks rooted at BLOCK. The
6029 number of elements in the vector is stored in N_BLOCKS_P. The
6030 vector is dynamically allocated; it is the caller's responsibility
6031 to call `free' on the pointer returned. */
6033 static tree *
6034 get_block_vector (block, n_blocks_p)
6035 tree block;
6036 int *n_blocks_p;
6038 tree *block_vector;
6040 *n_blocks_p = all_blocks (block, NULL);
6041 block_vector = (tree *) xmalloc (*n_blocks_p * sizeof (tree));
6042 all_blocks (block, block_vector);
6044 return block_vector;
6047 static int next_block_index = 2;
6049 /* Set BLOCK_NUMBER for all the blocks in FN. */
6051 void
6052 number_blocks (fn)
6053 tree fn;
6055 int i;
6056 int n_blocks;
6057 tree *block_vector;
6059 /* For SDB and XCOFF debugging output, we start numbering the blocks
6060 from 1 within each function, rather than keeping a running
6061 count. */
6062 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
6063 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
6064 next_block_index = 1;
6065 #endif
6067 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
6069 /* The top-level BLOCK isn't numbered at all. */
6070 for (i = 1; i < n_blocks; ++i)
6071 /* We number the blocks from two. */
6072 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
6074 free (block_vector);
6076 return;
6079 /* If VAR is present in a subblock of BLOCK, return the subblock. */
6081 tree
6082 debug_find_var_in_block_tree (var, block)
6083 tree var;
6084 tree block;
6086 tree t;
6088 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
6089 if (t == var)
6090 return block;
6092 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
6094 tree ret = debug_find_var_in_block_tree (var, t);
6095 if (ret)
6096 return ret;
6099 return NULL_TREE;
6102 /* Allocate a function structure and reset its contents to the defaults. */
6104 static void
6105 prepare_function_start ()
6107 cfun = (struct function *) ggc_alloc_cleared (sizeof (struct function));
6109 init_stmt_for_function ();
6110 init_eh_for_function ();
6112 cse_not_expected = ! optimize;
6114 /* Caller save not needed yet. */
6115 caller_save_needed = 0;
6117 /* No stack slots have been made yet. */
6118 stack_slot_list = 0;
6120 current_function_has_nonlocal_label = 0;
6121 current_function_has_nonlocal_goto = 0;
6123 /* There is no stack slot for handling nonlocal gotos. */
6124 nonlocal_goto_handler_slots = 0;
6125 nonlocal_goto_stack_level = 0;
6127 /* No labels have been declared for nonlocal use. */
6128 nonlocal_labels = 0;
6129 nonlocal_goto_handler_labels = 0;
6131 /* No function calls so far in this function. */
6132 function_call_count = 0;
6134 /* No parm regs have been allocated.
6135 (This is important for output_inline_function.) */
6136 max_parm_reg = LAST_VIRTUAL_REGISTER + 1;
6138 /* Initialize the RTL mechanism. */
6139 init_emit ();
6141 /* Initialize the queue of pending postincrement and postdecrements,
6142 and some other info in expr.c. */
6143 init_expr ();
6145 /* We haven't done register allocation yet. */
6146 reg_renumber = 0;
6148 init_varasm_status (cfun);
6150 /* Clear out data used for inlining. */
6151 cfun->inlinable = 0;
6152 cfun->original_decl_initial = 0;
6153 cfun->original_arg_vector = 0;
6155 cfun->stack_alignment_needed = STACK_BOUNDARY;
6156 cfun->preferred_stack_boundary = STACK_BOUNDARY;
6158 /* Set if a call to setjmp is seen. */
6159 current_function_calls_setjmp = 0;
6161 /* Set if a call to longjmp is seen. */
6162 current_function_calls_longjmp = 0;
6164 current_function_calls_alloca = 0;
6165 current_function_calls_eh_return = 0;
6166 current_function_calls_constant_p = 0;
6167 current_function_contains_functions = 0;
6168 current_function_is_leaf = 0;
6169 current_function_nothrow = 0;
6170 current_function_sp_is_unchanging = 0;
6171 current_function_uses_only_leaf_regs = 0;
6172 current_function_has_computed_jump = 0;
6173 current_function_is_thunk = 0;
6175 current_function_returns_pcc_struct = 0;
6176 current_function_returns_struct = 0;
6177 current_function_epilogue_delay_list = 0;
6178 current_function_uses_const_pool = 0;
6179 current_function_uses_pic_offset_table = 0;
6180 current_function_cannot_inline = 0;
6182 /* We have not yet needed to make a label to jump to for tail-recursion. */
6183 tail_recursion_label = 0;
6185 /* We haven't had a need to make a save area for ap yet. */
6186 arg_pointer_save_area = 0;
6188 /* No stack slots allocated yet. */
6189 frame_offset = 0;
6191 /* No SAVE_EXPRs in this function yet. */
6192 save_expr_regs = 0;
6194 /* No RTL_EXPRs in this function yet. */
6195 rtl_expr_chain = 0;
6197 /* Set up to allocate temporaries. */
6198 init_temp_slots ();
6200 /* Indicate that we need to distinguish between the return value of the
6201 present function and the return value of a function being called. */
6202 rtx_equal_function_value_matters = 1;
6204 /* Indicate that we have not instantiated virtual registers yet. */
6205 virtuals_instantiated = 0;
6207 /* Indicate that we want CONCATs now. */
6208 generating_concat_p = 1;
6210 /* Indicate we have no need of a frame pointer yet. */
6211 frame_pointer_needed = 0;
6213 /* By default assume not stdarg. */
6214 current_function_stdarg = 0;
6216 /* We haven't made any trampolines for this function yet. */
6217 trampoline_list = 0;
6219 init_pending_stack_adjust ();
6220 inhibit_defer_pop = 0;
6222 current_function_outgoing_args_size = 0;
6224 current_function_funcdef_no = funcdef_no++;
6226 cfun->arc_profile = profile_arc_flag || flag_test_coverage;
6228 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
6230 cfun->max_jumptable_ents = 0;
6232 (*lang_hooks.function.init) (cfun);
6233 if (init_machine_status)
6234 cfun->machine = (*init_machine_status) ();
6237 /* Initialize the rtl expansion mechanism so that we can do simple things
6238 like generate sequences. This is used to provide a context during global
6239 initialization of some passes. */
6240 void
6241 init_dummy_function_start ()
6243 prepare_function_start ();
6246 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
6247 and initialize static variables for generating RTL for the statements
6248 of the function. */
6250 void
6251 init_function_start (subr, filename, line)
6252 tree subr;
6253 const char *filename;
6254 int line;
6256 prepare_function_start ();
6258 current_function_name = (*lang_hooks.decl_printable_name) (subr, 2);
6259 cfun->decl = subr;
6261 /* Nonzero if this is a nested function that uses a static chain. */
6263 current_function_needs_context
6264 = (decl_function_context (current_function_decl) != 0
6265 && ! DECL_NO_STATIC_CHAIN (current_function_decl));
6267 /* Within function body, compute a type's size as soon it is laid out. */
6268 immediate_size_expand++;
6270 /* Prevent ever trying to delete the first instruction of a function.
6271 Also tell final how to output a linenum before the function prologue.
6272 Note linenums could be missing, e.g. when compiling a Java .class file. */
6273 if (line > 0)
6274 emit_line_note (filename, line);
6276 /* Make sure first insn is a note even if we don't want linenums.
6277 This makes sure the first insn will never be deleted.
6278 Also, final expects a note to appear there. */
6279 emit_note (NULL, NOTE_INSN_DELETED);
6281 /* Set flags used by final.c. */
6282 if (aggregate_value_p (DECL_RESULT (subr)))
6284 #ifdef PCC_STATIC_STRUCT_RETURN
6285 current_function_returns_pcc_struct = 1;
6286 #endif
6287 current_function_returns_struct = 1;
6290 /* Warn if this value is an aggregate type,
6291 regardless of which calling convention we are using for it. */
6292 if (warn_aggregate_return
6293 && AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
6294 warning ("function returns an aggregate");
6296 current_function_returns_pointer
6297 = POINTER_TYPE_P (TREE_TYPE (DECL_RESULT (subr)));
6300 /* Make sure all values used by the optimization passes have sane
6301 defaults. */
6302 void
6303 init_function_for_compilation ()
6305 reg_renumber = 0;
6307 /* No prologue/epilogue insns yet. */
6308 VARRAY_GROW (prologue, 0);
6309 VARRAY_GROW (epilogue, 0);
6310 VARRAY_GROW (sibcall_epilogue, 0);
6313 /* Expand a call to __main at the beginning of a possible main function. */
6315 #if defined(INIT_SECTION_ASM_OP) && !defined(INVOKE__main)
6316 #undef HAS_INIT_SECTION
6317 #define HAS_INIT_SECTION
6318 #endif
6320 void
6321 expand_main_function ()
6323 #ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
6324 if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
6326 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
6327 rtx tmp, seq;
6329 start_sequence ();
6330 /* Forcibly align the stack. */
6331 #ifdef STACK_GROWS_DOWNWARD
6332 tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
6333 stack_pointer_rtx, 1, OPTAB_WIDEN);
6334 #else
6335 tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
6336 GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
6337 tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
6338 stack_pointer_rtx, 1, OPTAB_WIDEN);
6339 #endif
6340 if (tmp != stack_pointer_rtx)
6341 emit_move_insn (stack_pointer_rtx, tmp);
6343 /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
6344 tmp = force_reg (Pmode, const0_rtx);
6345 allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
6346 seq = get_insns ();
6347 end_sequence ();
6349 for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
6350 if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
6351 break;
6352 if (tmp)
6353 emit_insn_before (seq, tmp);
6354 else
6355 emit_insn (seq);
6357 #endif
6359 #ifndef HAS_INIT_SECTION
6360 emit_library_call (gen_rtx_SYMBOL_REF (Pmode, NAME__MAIN), LCT_NORMAL,
6361 VOIDmode, 0);
6362 #endif
6365 /* The PENDING_SIZES represent the sizes of variable-sized types.
6366 Create RTL for the various sizes now (using temporary variables),
6367 so that we can refer to the sizes from the RTL we are generating
6368 for the current function. The PENDING_SIZES are a TREE_LIST. The
6369 TREE_VALUE of each node is a SAVE_EXPR. */
6371 void
6372 expand_pending_sizes (pending_sizes)
6373 tree pending_sizes;
6375 tree tem;
6377 /* Evaluate now the sizes of any types declared among the arguments. */
6378 for (tem = pending_sizes; tem; tem = TREE_CHAIN (tem))
6380 expand_expr (TREE_VALUE (tem), const0_rtx, VOIDmode, 0);
6381 /* Flush the queue in case this parameter declaration has
6382 side-effects. */
6383 emit_queue ();
6387 /* Start the RTL for a new function, and set variables used for
6388 emitting RTL.
6389 SUBR is the FUNCTION_DECL node.
6390 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
6391 the function's parameters, which must be run at any return statement. */
6393 void
6394 expand_function_start (subr, parms_have_cleanups)
6395 tree subr;
6396 int parms_have_cleanups;
6398 tree tem;
6399 rtx last_ptr = NULL_RTX;
6401 /* Make sure volatile mem refs aren't considered
6402 valid operands of arithmetic insns. */
6403 init_recog_no_volatile ();
6405 current_function_instrument_entry_exit
6406 = (flag_instrument_function_entry_exit
6407 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6409 current_function_profile
6410 = (profile_flag
6411 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
6413 current_function_limit_stack
6414 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
6416 /* If function gets a static chain arg, store it in the stack frame.
6417 Do this first, so it gets the first stack slot offset. */
6418 if (current_function_needs_context)
6420 last_ptr = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
6422 /* Delay copying static chain if it is not a register to avoid
6423 conflicts with regs used for parameters. */
6424 if (! SMALL_REGISTER_CLASSES
6425 || GET_CODE (static_chain_incoming_rtx) == REG)
6426 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6429 /* If the parameters of this function need cleaning up, get a label
6430 for the beginning of the code which executes those cleanups. This must
6431 be done before doing anything with return_label. */
6432 if (parms_have_cleanups)
6433 cleanup_label = gen_label_rtx ();
6434 else
6435 cleanup_label = 0;
6437 /* Make the label for return statements to jump to. Do not special
6438 case machines with special return instructions -- they will be
6439 handled later during jump, ifcvt, or epilogue creation. */
6440 return_label = gen_label_rtx ();
6442 /* Initialize rtx used to return the value. */
6443 /* Do this before assign_parms so that we copy the struct value address
6444 before any library calls that assign parms might generate. */
6446 /* Decide whether to return the value in memory or in a register. */
6447 if (aggregate_value_p (DECL_RESULT (subr)))
6449 /* Returning something that won't go in a register. */
6450 rtx value_address = 0;
6452 #ifdef PCC_STATIC_STRUCT_RETURN
6453 if (current_function_returns_pcc_struct)
6455 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
6456 value_address = assemble_static_space (size);
6458 else
6459 #endif
6461 /* Expect to be passed the address of a place to store the value.
6462 If it is passed as an argument, assign_parms will take care of
6463 it. */
6464 if (struct_value_incoming_rtx)
6466 value_address = gen_reg_rtx (Pmode);
6467 emit_move_insn (value_address, struct_value_incoming_rtx);
6470 if (value_address)
6472 rtx x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), value_address);
6473 set_mem_attributes (x, DECL_RESULT (subr), 1);
6474 SET_DECL_RTL (DECL_RESULT (subr), x);
6477 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
6478 /* If return mode is void, this decl rtl should not be used. */
6479 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
6480 else
6482 /* Compute the return values into a pseudo reg, which we will copy
6483 into the true return register after the cleanups are done. */
6485 /* In order to figure out what mode to use for the pseudo, we
6486 figure out what the mode of the eventual return register will
6487 actually be, and use that. */
6488 rtx hard_reg
6489 = hard_function_value (TREE_TYPE (DECL_RESULT (subr)),
6490 subr, 1);
6492 /* Structures that are returned in registers are not aggregate_value_p,
6493 so we may see a PARALLEL or a REG. */
6494 if (REG_P (hard_reg))
6495 SET_DECL_RTL (DECL_RESULT (subr), gen_reg_rtx (GET_MODE (hard_reg)));
6496 else if (GET_CODE (hard_reg) == PARALLEL)
6497 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
6498 else
6499 abort ();
6501 /* Set DECL_REGISTER flag so that expand_function_end will copy the
6502 result to the real return register(s). */
6503 DECL_REGISTER (DECL_RESULT (subr)) = 1;
6506 /* Initialize rtx for parameters and local variables.
6507 In some cases this requires emitting insns. */
6509 assign_parms (subr);
6511 /* Copy the static chain now if it wasn't a register. The delay is to
6512 avoid conflicts with the parameter passing registers. */
6514 if (SMALL_REGISTER_CLASSES && current_function_needs_context)
6515 if (GET_CODE (static_chain_incoming_rtx) != REG)
6516 emit_move_insn (last_ptr, static_chain_incoming_rtx);
6518 /* The following was moved from init_function_start.
6519 The move is supposed to make sdb output more accurate. */
6520 /* Indicate the beginning of the function body,
6521 as opposed to parm setup. */
6522 emit_note (NULL, NOTE_INSN_FUNCTION_BEG);
6524 if (GET_CODE (get_last_insn ()) != NOTE)
6525 emit_note (NULL, NOTE_INSN_DELETED);
6526 parm_birth_insn = get_last_insn ();
6528 context_display = 0;
6529 if (current_function_needs_context)
6531 /* Fetch static chain values for containing functions. */
6532 tem = decl_function_context (current_function_decl);
6533 /* Copy the static chain pointer into a pseudo. If we have
6534 small register classes, copy the value from memory if
6535 static_chain_incoming_rtx is a REG. */
6536 if (tem)
6538 /* If the static chain originally came in a register, put it back
6539 there, then move it out in the next insn. The reason for
6540 this peculiar code is to satisfy function integration. */
6541 if (SMALL_REGISTER_CLASSES
6542 && GET_CODE (static_chain_incoming_rtx) == REG)
6543 emit_move_insn (static_chain_incoming_rtx, last_ptr);
6544 last_ptr = copy_to_reg (static_chain_incoming_rtx);
6547 while (tem)
6549 tree rtlexp = make_node (RTL_EXPR);
6551 RTL_EXPR_RTL (rtlexp) = last_ptr;
6552 context_display = tree_cons (tem, rtlexp, context_display);
6553 tem = decl_function_context (tem);
6554 if (tem == 0)
6555 break;
6556 /* Chain thru stack frames, assuming pointer to next lexical frame
6557 is found at the place we always store it. */
6558 #ifdef FRAME_GROWS_DOWNWARD
6559 last_ptr = plus_constant (last_ptr,
6560 -(HOST_WIDE_INT) GET_MODE_SIZE (Pmode));
6561 #endif
6562 last_ptr = gen_rtx_MEM (Pmode, memory_address (Pmode, last_ptr));
6563 set_mem_alias_set (last_ptr, get_frame_alias_set ());
6564 last_ptr = copy_to_reg (last_ptr);
6566 /* If we are not optimizing, ensure that we know that this
6567 piece of context is live over the entire function. */
6568 if (! optimize)
6569 save_expr_regs = gen_rtx_EXPR_LIST (VOIDmode, last_ptr,
6570 save_expr_regs);
6574 if (current_function_instrument_entry_exit)
6576 rtx fun = DECL_RTL (current_function_decl);
6577 if (GET_CODE (fun) == MEM)
6578 fun = XEXP (fun, 0);
6579 else
6580 abort ();
6581 emit_library_call (profile_function_entry_libfunc, LCT_NORMAL, VOIDmode,
6582 2, fun, Pmode,
6583 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6585 hard_frame_pointer_rtx),
6586 Pmode);
6589 if (current_function_profile)
6591 #ifdef PROFILE_HOOK
6592 PROFILE_HOOK (current_function_funcdef_no);
6593 #endif
6596 /* After the display initializations is where the tail-recursion label
6597 should go, if we end up needing one. Ensure we have a NOTE here
6598 since some things (like trampolines) get placed before this. */
6599 tail_recursion_reentry = emit_note (NULL, NOTE_INSN_DELETED);
6601 /* Evaluate now the sizes of any types declared among the arguments. */
6602 expand_pending_sizes (nreverse (get_pending_sizes ()));
6604 /* Make sure there is a line number after the function entry setup code. */
6605 force_next_line_note ();
6608 /* Undo the effects of init_dummy_function_start. */
6609 void
6610 expand_dummy_function_end ()
6612 /* End any sequences that failed to be closed due to syntax errors. */
6613 while (in_sequence_p ())
6614 end_sequence ();
6616 /* Outside function body, can't compute type's actual size
6617 until next function's body starts. */
6619 free_after_parsing (cfun);
6620 free_after_compilation (cfun);
6621 cfun = 0;
6624 /* Call DOIT for each hard register used as a return value from
6625 the current function. */
6627 void
6628 diddle_return_value (doit, arg)
6629 void (*doit) PARAMS ((rtx, void *));
6630 void *arg;
6632 rtx outgoing = current_function_return_rtx;
6634 if (! outgoing)
6635 return;
6637 if (GET_CODE (outgoing) == REG)
6638 (*doit) (outgoing, arg);
6639 else if (GET_CODE (outgoing) == PARALLEL)
6641 int i;
6643 for (i = 0; i < XVECLEN (outgoing, 0); i++)
6645 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
6647 if (GET_CODE (x) == REG && REGNO (x) < FIRST_PSEUDO_REGISTER)
6648 (*doit) (x, arg);
6653 static void
6654 do_clobber_return_reg (reg, arg)
6655 rtx reg;
6656 void *arg ATTRIBUTE_UNUSED;
6658 emit_insn (gen_rtx_CLOBBER (VOIDmode, reg));
6661 void
6662 clobber_return_register ()
6664 diddle_return_value (do_clobber_return_reg, NULL);
6666 /* In case we do use pseudo to return value, clobber it too. */
6667 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6669 tree decl_result = DECL_RESULT (current_function_decl);
6670 rtx decl_rtl = DECL_RTL (decl_result);
6671 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
6673 do_clobber_return_reg (decl_rtl, NULL);
6678 static void
6679 do_use_return_reg (reg, arg)
6680 rtx reg;
6681 void *arg ATTRIBUTE_UNUSED;
6683 emit_insn (gen_rtx_USE (VOIDmode, reg));
6686 void
6687 use_return_register ()
6689 diddle_return_value (do_use_return_reg, NULL);
6692 static GTY(()) rtx initial_trampoline;
6694 /* Generate RTL for the end of the current function.
6695 FILENAME and LINE are the current position in the source file.
6697 It is up to language-specific callers to do cleanups for parameters--
6698 or else, supply 1 for END_BINDINGS and we will call expand_end_bindings. */
6700 void
6701 expand_function_end (filename, line, end_bindings)
6702 const char *filename;
6703 int line;
6704 int end_bindings;
6706 tree link;
6707 rtx clobber_after;
6709 finish_expr_for_function ();
6711 /* If arg_pointer_save_area was referenced only from a nested
6712 function, we will not have initialized it yet. Do that now. */
6713 if (arg_pointer_save_area && ! cfun->arg_pointer_save_area_init)
6714 get_arg_pointer_save_area (cfun);
6716 #ifdef NON_SAVING_SETJMP
6717 /* Don't put any variables in registers if we call setjmp
6718 on a machine that fails to restore the registers. */
6719 if (NON_SAVING_SETJMP && current_function_calls_setjmp)
6721 if (DECL_INITIAL (current_function_decl) != error_mark_node)
6722 setjmp_protect (DECL_INITIAL (current_function_decl));
6724 setjmp_protect_args ();
6726 #endif
6728 /* Initialize any trampolines required by this function. */
6729 for (link = trampoline_list; link; link = TREE_CHAIN (link))
6731 tree function = TREE_PURPOSE (link);
6732 rtx context ATTRIBUTE_UNUSED = lookup_static_chain (function);
6733 rtx tramp = RTL_EXPR_RTL (TREE_VALUE (link));
6734 #ifdef TRAMPOLINE_TEMPLATE
6735 rtx blktramp;
6736 #endif
6737 rtx seq;
6739 #ifdef TRAMPOLINE_TEMPLATE
6740 /* First make sure this compilation has a template for
6741 initializing trampolines. */
6742 if (initial_trampoline == 0)
6744 initial_trampoline
6745 = gen_rtx_MEM (BLKmode, assemble_trampoline_template ());
6746 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
6748 #endif
6750 /* Generate insns to initialize the trampoline. */
6751 start_sequence ();
6752 tramp = round_trampoline_addr (XEXP (tramp, 0));
6753 #ifdef TRAMPOLINE_TEMPLATE
6754 blktramp = replace_equiv_address (initial_trampoline, tramp);
6755 emit_block_move (blktramp, initial_trampoline,
6756 GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL);
6757 #endif
6758 INITIALIZE_TRAMPOLINE (tramp, XEXP (DECL_RTL (function), 0), context);
6759 seq = get_insns ();
6760 end_sequence ();
6762 /* Put those insns at entry to the containing function (this one). */
6763 emit_insn_before (seq, tail_recursion_reentry);
6766 /* If we are doing stack checking and this function makes calls,
6767 do a stack probe at the start of the function to ensure we have enough
6768 space for another stack frame. */
6769 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
6771 rtx insn, seq;
6773 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6774 if (GET_CODE (insn) == CALL_INSN)
6776 start_sequence ();
6777 probe_stack_range (STACK_CHECK_PROTECT,
6778 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
6779 seq = get_insns ();
6780 end_sequence ();
6781 emit_insn_before (seq, tail_recursion_reentry);
6782 break;
6786 /* Warn about unused parms if extra warnings were specified. */
6787 /* Either ``-Wextra -Wunused'' or ``-Wunused-parameter'' enables this
6788 warning. WARN_UNUSED_PARAMETER is negative when set by
6789 -Wunused. Note that -Wall implies -Wunused, so ``-Wall -Wextra'' will
6790 also give these warnings. */
6791 if (warn_unused_parameter > 0
6792 || (warn_unused_parameter < 0 && extra_warnings))
6794 tree decl;
6796 for (decl = DECL_ARGUMENTS (current_function_decl);
6797 decl; decl = TREE_CHAIN (decl))
6798 if (! TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
6799 && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl))
6800 warning_with_decl (decl, "unused parameter `%s'");
6803 /* Delete handlers for nonlocal gotos if nothing uses them. */
6804 if (nonlocal_goto_handler_slots != 0
6805 && ! current_function_has_nonlocal_label)
6806 delete_handlers ();
6808 /* End any sequences that failed to be closed due to syntax errors. */
6809 while (in_sequence_p ())
6810 end_sequence ();
6812 /* Outside function body, can't compute type's actual size
6813 until next function's body starts. */
6814 immediate_size_expand--;
6816 clear_pending_stack_adjust ();
6817 do_pending_stack_adjust ();
6819 /* Mark the end of the function body.
6820 If control reaches this insn, the function can drop through
6821 without returning a value. */
6822 emit_note (NULL, NOTE_INSN_FUNCTION_END);
6824 /* Must mark the last line number note in the function, so that the test
6825 coverage code can avoid counting the last line twice. This just tells
6826 the code to ignore the immediately following line note, since there
6827 already exists a copy of this note somewhere above. This line number
6828 note is still needed for debugging though, so we can't delete it. */
6829 if (flag_test_coverage)
6830 emit_note (NULL, NOTE_INSN_REPEATED_LINE_NUMBER);
6832 /* Output a linenumber for the end of the function.
6833 SDB depends on this. */
6834 emit_line_note_force (filename, line);
6836 /* Before the return label (if any), clobber the return
6837 registers so that they are not propagated live to the rest of
6838 the function. This can only happen with functions that drop
6839 through; if there had been a return statement, there would
6840 have either been a return rtx, or a jump to the return label.
6842 We delay actual code generation after the current_function_value_rtx
6843 is computed. */
6844 clobber_after = get_last_insn ();
6846 /* Output the label for the actual return from the function,
6847 if one is expected. This happens either because a function epilogue
6848 is used instead of a return instruction, or because a return was done
6849 with a goto in order to run local cleanups, or because of pcc-style
6850 structure returning. */
6851 if (return_label)
6852 emit_label (return_label);
6854 /* C++ uses this. */
6855 if (end_bindings)
6856 expand_end_bindings (0, 0, 0);
6858 if (current_function_instrument_entry_exit)
6860 rtx fun = DECL_RTL (current_function_decl);
6861 if (GET_CODE (fun) == MEM)
6862 fun = XEXP (fun, 0);
6863 else
6864 abort ();
6865 emit_library_call (profile_function_exit_libfunc, LCT_NORMAL, VOIDmode,
6866 2, fun, Pmode,
6867 expand_builtin_return_addr (BUILT_IN_RETURN_ADDRESS,
6869 hard_frame_pointer_rtx),
6870 Pmode);
6873 /* Let except.c know where it should emit the call to unregister
6874 the function context for sjlj exceptions. */
6875 if (flag_exceptions && USING_SJLJ_EXCEPTIONS)
6876 sjlj_emit_function_exit_after (get_last_insn ());
6878 /* If we had calls to alloca, and this machine needs
6879 an accurate stack pointer to exit the function,
6880 insert some code to save and restore the stack pointer. */
6881 #ifdef EXIT_IGNORE_STACK
6882 if (! EXIT_IGNORE_STACK)
6883 #endif
6884 if (current_function_calls_alloca)
6886 rtx tem = 0;
6888 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
6889 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
6892 /* If scalar return value was computed in a pseudo-reg, or was a named
6893 return value that got dumped to the stack, copy that to the hard
6894 return register. */
6895 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
6897 tree decl_result = DECL_RESULT (current_function_decl);
6898 rtx decl_rtl = DECL_RTL (decl_result);
6900 if (REG_P (decl_rtl)
6901 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
6902 : DECL_REGISTER (decl_result))
6904 rtx real_decl_rtl = current_function_return_rtx;
6906 /* This should be set in assign_parms. */
6907 if (! REG_FUNCTION_VALUE_P (real_decl_rtl))
6908 abort ();
6910 /* If this is a BLKmode structure being returned in registers,
6911 then use the mode computed in expand_return. Note that if
6912 decl_rtl is memory, then its mode may have been changed,
6913 but that current_function_return_rtx has not. */
6914 if (GET_MODE (real_decl_rtl) == BLKmode)
6915 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
6917 /* If a named return value dumped decl_return to memory, then
6918 we may need to re-do the PROMOTE_MODE signed/unsigned
6919 extension. */
6920 if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
6922 int unsignedp = TREE_UNSIGNED (TREE_TYPE (decl_result));
6924 #ifdef PROMOTE_FUNCTION_RETURN
6925 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
6926 &unsignedp, 1);
6927 #endif
6929 convert_move (real_decl_rtl, decl_rtl, unsignedp);
6931 else if (GET_CODE (real_decl_rtl) == PARALLEL)
6933 /* If expand_function_start has created a PARALLEL for decl_rtl,
6934 move the result to the real return registers. Otherwise, do
6935 a group load from decl_rtl for a named return. */
6936 if (GET_CODE (decl_rtl) == PARALLEL)
6937 emit_group_move (real_decl_rtl, decl_rtl);
6938 else
6939 emit_group_load (real_decl_rtl, decl_rtl,
6940 int_size_in_bytes (TREE_TYPE (decl_result)));
6942 else
6943 emit_move_insn (real_decl_rtl, decl_rtl);
6947 /* If returning a structure, arrange to return the address of the value
6948 in a place where debuggers expect to find it.
6950 If returning a structure PCC style,
6951 the caller also depends on this value.
6952 And current_function_returns_pcc_struct is not necessarily set. */
6953 if (current_function_returns_struct
6954 || current_function_returns_pcc_struct)
6956 rtx value_address
6957 = XEXP (DECL_RTL (DECL_RESULT (current_function_decl)), 0);
6958 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
6959 #ifdef FUNCTION_OUTGOING_VALUE
6960 rtx outgoing
6961 = FUNCTION_OUTGOING_VALUE (build_pointer_type (type),
6962 current_function_decl);
6963 #else
6964 rtx outgoing
6965 = FUNCTION_VALUE (build_pointer_type (type), current_function_decl);
6966 #endif
6968 /* Mark this as a function return value so integrate will delete the
6969 assignment and USE below when inlining this function. */
6970 REG_FUNCTION_VALUE_P (outgoing) = 1;
6972 #ifdef POINTERS_EXTEND_UNSIGNED
6973 /* The address may be ptr_mode and OUTGOING may be Pmode. */
6974 if (GET_MODE (outgoing) != GET_MODE (value_address))
6975 value_address = convert_memory_address (GET_MODE (outgoing),
6976 value_address);
6977 #endif
6979 emit_move_insn (outgoing, value_address);
6981 /* Show return register used to hold result (in this case the address
6982 of the result. */
6983 current_function_return_rtx = outgoing;
6986 /* If this is an implementation of throw, do what's necessary to
6987 communicate between __builtin_eh_return and the epilogue. */
6988 expand_eh_return ();
6990 /* Emit the actual code to clobber return register. */
6992 rtx seq, after;
6994 start_sequence ();
6995 clobber_return_register ();
6996 seq = get_insns ();
6997 end_sequence ();
6999 after = emit_insn_after (seq, clobber_after);
7001 if (clobber_after != after)
7002 cfun->x_clobber_return_insn = after;
7005 /* ??? This should no longer be necessary since stupid is no longer with
7006 us, but there are some parts of the compiler (eg reload_combine, and
7007 sh mach_dep_reorg) that still try and compute their own lifetime info
7008 instead of using the general framework. */
7009 use_return_register ();
7011 /* Fix up any gotos that jumped out to the outermost
7012 binding level of the function.
7013 Must follow emitting RETURN_LABEL. */
7015 /* If you have any cleanups to do at this point,
7016 and they need to create temporary variables,
7017 then you will lose. */
7018 expand_fixups (get_insns ());
7022 get_arg_pointer_save_area (f)
7023 struct function *f;
7025 rtx ret = f->x_arg_pointer_save_area;
7027 if (! ret)
7029 ret = assign_stack_local_1 (Pmode, GET_MODE_SIZE (Pmode), 0, f);
7030 f->x_arg_pointer_save_area = ret;
7033 if (f == cfun && ! f->arg_pointer_save_area_init)
7035 rtx seq;
7037 /* Save the arg pointer at the beginning of the function. The
7038 generated stack slot may not be a valid memory address, so we
7039 have to check it and fix it if necessary. */
7040 start_sequence ();
7041 emit_move_insn (validize_mem (ret), virtual_incoming_args_rtx);
7042 seq = get_insns ();
7043 end_sequence ();
7045 push_topmost_sequence ();
7046 emit_insn_after (seq, get_insns ());
7047 pop_topmost_sequence ();
7050 return ret;
7053 /* Extend a vector that records the INSN_UIDs of INSNS
7054 (a list of one or more insns). */
7056 static void
7057 record_insns (insns, vecp)
7058 rtx insns;
7059 varray_type *vecp;
7061 int i, len;
7062 rtx tmp;
7064 tmp = insns;
7065 len = 0;
7066 while (tmp != NULL_RTX)
7068 len++;
7069 tmp = NEXT_INSN (tmp);
7072 i = VARRAY_SIZE (*vecp);
7073 VARRAY_GROW (*vecp, i + len);
7074 tmp = insns;
7075 while (tmp != NULL_RTX)
7077 VARRAY_INT (*vecp, i) = INSN_UID (tmp);
7078 i++;
7079 tmp = NEXT_INSN (tmp);
7083 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
7084 be running after reorg, SEQUENCE rtl is possible. */
7086 static int
7087 contains (insn, vec)
7088 rtx insn;
7089 varray_type vec;
7091 int i, j;
7093 if (GET_CODE (insn) == INSN
7094 && GET_CODE (PATTERN (insn)) == SEQUENCE)
7096 int count = 0;
7097 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
7098 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7099 if (INSN_UID (XVECEXP (PATTERN (insn), 0, i)) == VARRAY_INT (vec, j))
7100 count++;
7101 return count;
7103 else
7105 for (j = VARRAY_SIZE (vec) - 1; j >= 0; --j)
7106 if (INSN_UID (insn) == VARRAY_INT (vec, j))
7107 return 1;
7109 return 0;
7113 prologue_epilogue_contains (insn)
7114 rtx insn;
7116 if (contains (insn, prologue))
7117 return 1;
7118 if (contains (insn, epilogue))
7119 return 1;
7120 return 0;
7124 sibcall_epilogue_contains (insn)
7125 rtx insn;
7127 if (sibcall_epilogue)
7128 return contains (insn, sibcall_epilogue);
7129 return 0;
7132 #ifdef HAVE_return
7133 /* Insert gen_return at the end of block BB. This also means updating
7134 block_for_insn appropriately. */
7136 static void
7137 emit_return_into_block (bb, line_note)
7138 basic_block bb;
7139 rtx line_note;
7141 emit_jump_insn_after (gen_return (), bb->end);
7142 if (line_note)
7143 emit_line_note_after (NOTE_SOURCE_FILE (line_note),
7144 NOTE_LINE_NUMBER (line_note), PREV_INSN (bb->end));
7146 #endif /* HAVE_return */
7148 #if defined(HAVE_epilogue) && defined(INCOMING_RETURN_ADDR_RTX)
7150 /* These functions convert the epilogue into a variant that does not modify the
7151 stack pointer. This is used in cases where a function returns an object
7152 whose size is not known until it is computed. The called function leaves the
7153 object on the stack, leaves the stack depressed, and returns a pointer to
7154 the object.
7156 What we need to do is track all modifications and references to the stack
7157 pointer, deleting the modifications and changing the references to point to
7158 the location the stack pointer would have pointed to had the modifications
7159 taken place.
7161 These functions need to be portable so we need to make as few assumptions
7162 about the epilogue as we can. However, the epilogue basically contains
7163 three things: instructions to reset the stack pointer, instructions to
7164 reload registers, possibly including the frame pointer, and an
7165 instruction to return to the caller.
7167 If we can't be sure of what a relevant epilogue insn is doing, we abort.
7168 We also make no attempt to validate the insns we make since if they are
7169 invalid, we probably can't do anything valid. The intent is that these
7170 routines get "smarter" as more and more machines start to use them and
7171 they try operating on different epilogues.
7173 We use the following structure to track what the part of the epilogue that
7174 we've already processed has done. We keep two copies of the SP equivalence,
7175 one for use during the insn we are processing and one for use in the next
7176 insn. The difference is because one part of a PARALLEL may adjust SP
7177 and the other may use it. */
7179 struct epi_info
7181 rtx sp_equiv_reg; /* REG that SP is set from, perhaps SP. */
7182 HOST_WIDE_INT sp_offset; /* Offset from SP_EQUIV_REG of present SP. */
7183 rtx new_sp_equiv_reg; /* REG to be used at end of insn. */
7184 HOST_WIDE_INT new_sp_offset; /* Offset to be used at end of insn. */
7185 rtx equiv_reg_src; /* If nonzero, the value that SP_EQUIV_REG
7186 should be set to once we no longer need
7187 its value. */
7190 static void handle_epilogue_set PARAMS ((rtx, struct epi_info *));
7191 static void emit_equiv_load PARAMS ((struct epi_info *));
7193 /* Modify INSN, a list of one or more insns that is part of the epilogue, to
7194 no modifications to the stack pointer. Return the new list of insns. */
7196 static rtx
7197 keep_stack_depressed (insns)
7198 rtx insns;
7200 int j;
7201 struct epi_info info;
7202 rtx insn, next;
7204 /* If the epilogue is just a single instruction, it ust be OK as is. */
7206 if (NEXT_INSN (insns) == NULL_RTX)
7207 return insns;
7209 /* Otherwise, start a sequence, initialize the information we have, and
7210 process all the insns we were given. */
7211 start_sequence ();
7213 info.sp_equiv_reg = stack_pointer_rtx;
7214 info.sp_offset = 0;
7215 info.equiv_reg_src = 0;
7217 insn = insns;
7218 next = NULL_RTX;
7219 while (insn != NULL_RTX)
7221 next = NEXT_INSN (insn);
7223 if (!INSN_P (insn))
7225 add_insn (insn);
7226 insn = next;
7227 continue;
7230 /* If this insn references the register that SP is equivalent to and
7231 we have a pending load to that register, we must force out the load
7232 first and then indicate we no longer know what SP's equivalent is. */
7233 if (info.equiv_reg_src != 0
7234 && reg_referenced_p (info.sp_equiv_reg, PATTERN (insn)))
7236 emit_equiv_load (&info);
7237 info.sp_equiv_reg = 0;
7240 info.new_sp_equiv_reg = info.sp_equiv_reg;
7241 info.new_sp_offset = info.sp_offset;
7243 /* If this is a (RETURN) and the return address is on the stack,
7244 update the address and change to an indirect jump. */
7245 if (GET_CODE (PATTERN (insn)) == RETURN
7246 || (GET_CODE (PATTERN (insn)) == PARALLEL
7247 && GET_CODE (XVECEXP (PATTERN (insn), 0, 0)) == RETURN))
7249 rtx retaddr = INCOMING_RETURN_ADDR_RTX;
7250 rtx base = 0;
7251 HOST_WIDE_INT offset = 0;
7252 rtx jump_insn, jump_set;
7254 /* If the return address is in a register, we can emit the insn
7255 unchanged. Otherwise, it must be a MEM and we see what the
7256 base register and offset are. In any case, we have to emit any
7257 pending load to the equivalent reg of SP, if any. */
7258 if (GET_CODE (retaddr) == REG)
7260 emit_equiv_load (&info);
7261 add_insn (insn);
7262 insn = next;
7263 continue;
7265 else if (GET_CODE (retaddr) == MEM
7266 && GET_CODE (XEXP (retaddr, 0)) == REG)
7267 base = gen_rtx_REG (Pmode, REGNO (XEXP (retaddr, 0))), offset = 0;
7268 else if (GET_CODE (retaddr) == MEM
7269 && GET_CODE (XEXP (retaddr, 0)) == PLUS
7270 && GET_CODE (XEXP (XEXP (retaddr, 0), 0)) == REG
7271 && GET_CODE (XEXP (XEXP (retaddr, 0), 1)) == CONST_INT)
7273 base = gen_rtx_REG (Pmode, REGNO (XEXP (XEXP (retaddr, 0), 0)));
7274 offset = INTVAL (XEXP (XEXP (retaddr, 0), 1));
7276 else
7277 abort ();
7279 /* If the base of the location containing the return pointer
7280 is SP, we must update it with the replacement address. Otherwise,
7281 just build the necessary MEM. */
7282 retaddr = plus_constant (base, offset);
7283 if (base == stack_pointer_rtx)
7284 retaddr = simplify_replace_rtx (retaddr, stack_pointer_rtx,
7285 plus_constant (info.sp_equiv_reg,
7286 info.sp_offset));
7288 retaddr = gen_rtx_MEM (Pmode, retaddr);
7290 /* If there is a pending load to the equivalent register for SP
7291 and we reference that register, we must load our address into
7292 a scratch register and then do that load. */
7293 if (info.equiv_reg_src
7294 && reg_overlap_mentioned_p (info.equiv_reg_src, retaddr))
7296 unsigned int regno;
7297 rtx reg;
7299 for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
7300 if (HARD_REGNO_MODE_OK (regno, Pmode)
7301 && !fixed_regs[regno]
7302 && TEST_HARD_REG_BIT (regs_invalidated_by_call, regno)
7303 && !REGNO_REG_SET_P (EXIT_BLOCK_PTR->global_live_at_start,
7304 regno)
7305 && !refers_to_regno_p (regno,
7306 regno + HARD_REGNO_NREGS (regno,
7307 Pmode),
7308 info.equiv_reg_src, NULL))
7309 break;
7311 if (regno == FIRST_PSEUDO_REGISTER)
7312 abort ();
7314 reg = gen_rtx_REG (Pmode, regno);
7315 emit_move_insn (reg, retaddr);
7316 retaddr = reg;
7319 emit_equiv_load (&info);
7320 jump_insn = emit_jump_insn (gen_indirect_jump (retaddr));
7322 /* Show the SET in the above insn is a RETURN. */
7323 jump_set = single_set (jump_insn);
7324 if (jump_set == 0)
7325 abort ();
7326 else
7327 SET_IS_RETURN_P (jump_set) = 1;
7330 /* If SP is not mentioned in the pattern and its equivalent register, if
7331 any, is not modified, just emit it. Otherwise, if neither is set,
7332 replace the reference to SP and emit the insn. If none of those are
7333 true, handle each SET individually. */
7334 else if (!reg_mentioned_p (stack_pointer_rtx, PATTERN (insn))
7335 && (info.sp_equiv_reg == stack_pointer_rtx
7336 || !reg_set_p (info.sp_equiv_reg, insn)))
7337 add_insn (insn);
7338 else if (! reg_set_p (stack_pointer_rtx, insn)
7339 && (info.sp_equiv_reg == stack_pointer_rtx
7340 || !reg_set_p (info.sp_equiv_reg, insn)))
7342 if (! validate_replace_rtx (stack_pointer_rtx,
7343 plus_constant (info.sp_equiv_reg,
7344 info.sp_offset),
7345 insn))
7346 abort ();
7348 add_insn (insn);
7350 else if (GET_CODE (PATTERN (insn)) == SET)
7351 handle_epilogue_set (PATTERN (insn), &info);
7352 else if (GET_CODE (PATTERN (insn)) == PARALLEL)
7354 for (j = 0; j < XVECLEN (PATTERN (insn), 0); j++)
7355 if (GET_CODE (XVECEXP (PATTERN (insn), 0, j)) == SET)
7356 handle_epilogue_set (XVECEXP (PATTERN (insn), 0, j), &info);
7358 else
7359 add_insn (insn);
7361 info.sp_equiv_reg = info.new_sp_equiv_reg;
7362 info.sp_offset = info.new_sp_offset;
7364 insn = next;
7367 insns = get_insns ();
7368 end_sequence ();
7369 return insns;
7372 /* SET is a SET from an insn in the epilogue. P is a pointer to the epi_info
7373 structure that contains information about what we've seen so far. We
7374 process this SET by either updating that data or by emitting one or
7375 more insns. */
7377 static void
7378 handle_epilogue_set (set, p)
7379 rtx set;
7380 struct epi_info *p;
7382 /* First handle the case where we are setting SP. Record what it is being
7383 set from. If unknown, abort. */
7384 if (reg_set_p (stack_pointer_rtx, set))
7386 if (SET_DEST (set) != stack_pointer_rtx)
7387 abort ();
7389 if (GET_CODE (SET_SRC (set)) == PLUS
7390 && GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT)
7392 p->new_sp_equiv_reg = XEXP (SET_SRC (set), 0);
7393 p->new_sp_offset = INTVAL (XEXP (SET_SRC (set), 1));
7395 else
7396 p->new_sp_equiv_reg = SET_SRC (set), p->new_sp_offset = 0;
7398 /* If we are adjusting SP, we adjust from the old data. */
7399 if (p->new_sp_equiv_reg == stack_pointer_rtx)
7401 p->new_sp_equiv_reg = p->sp_equiv_reg;
7402 p->new_sp_offset += p->sp_offset;
7405 if (p->new_sp_equiv_reg == 0 || GET_CODE (p->new_sp_equiv_reg) != REG)
7406 abort ();
7408 return;
7411 /* Next handle the case where we are setting SP's equivalent register.
7412 If we already have a value to set it to, abort. We could update, but
7413 there seems little point in handling that case. Note that we have
7414 to allow for the case where we are setting the register set in
7415 the previous part of a PARALLEL inside a single insn. But use the
7416 old offset for any updates within this insn. */
7417 else if (p->new_sp_equiv_reg != 0 && reg_set_p (p->new_sp_equiv_reg, set))
7419 if (!rtx_equal_p (p->new_sp_equiv_reg, SET_DEST (set))
7420 || p->equiv_reg_src != 0)
7421 abort ();
7422 else
7423 p->equiv_reg_src
7424 = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7425 plus_constant (p->sp_equiv_reg,
7426 p->sp_offset));
7429 /* Otherwise, replace any references to SP in the insn to its new value
7430 and emit the insn. */
7431 else
7433 SET_SRC (set) = simplify_replace_rtx (SET_SRC (set), stack_pointer_rtx,
7434 plus_constant (p->sp_equiv_reg,
7435 p->sp_offset));
7436 SET_DEST (set) = simplify_replace_rtx (SET_DEST (set), stack_pointer_rtx,
7437 plus_constant (p->sp_equiv_reg,
7438 p->sp_offset));
7439 emit_insn (set);
7443 /* Emit an insn to do the load shown in p->equiv_reg_src, if needed. */
7445 static void
7446 emit_equiv_load (p)
7447 struct epi_info *p;
7449 if (p->equiv_reg_src != 0)
7450 emit_move_insn (p->sp_equiv_reg, p->equiv_reg_src);
7452 p->equiv_reg_src = 0;
7454 #endif
7456 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
7457 this into place with notes indicating where the prologue ends and where
7458 the epilogue begins. Update the basic block information when possible. */
7460 void
7461 thread_prologue_and_epilogue_insns (f)
7462 rtx f ATTRIBUTE_UNUSED;
7464 int inserted = 0;
7465 edge e;
7466 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
7467 rtx seq;
7468 #endif
7469 #ifdef HAVE_prologue
7470 rtx prologue_end = NULL_RTX;
7471 #endif
7472 #if defined (HAVE_epilogue) || defined(HAVE_return)
7473 rtx epilogue_end = NULL_RTX;
7474 #endif
7476 #ifdef HAVE_prologue
7477 if (HAVE_prologue)
7479 start_sequence ();
7480 seq = gen_prologue ();
7481 emit_insn (seq);
7483 /* Retain a map of the prologue insns. */
7484 record_insns (seq, &prologue);
7485 prologue_end = emit_note (NULL, NOTE_INSN_PROLOGUE_END);
7487 seq = get_insns ();
7488 end_sequence ();
7490 /* Can't deal with multiple successors of the entry block
7491 at the moment. Function should always have at least one
7492 entry point. */
7493 if (!ENTRY_BLOCK_PTR->succ || ENTRY_BLOCK_PTR->succ->succ_next)
7494 abort ();
7496 insert_insn_on_edge (seq, ENTRY_BLOCK_PTR->succ);
7497 inserted = 1;
7499 #endif
7501 /* If the exit block has no non-fake predecessors, we don't need
7502 an epilogue. */
7503 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7504 if ((e->flags & EDGE_FAKE) == 0)
7505 break;
7506 if (e == NULL)
7507 goto epilogue_done;
7509 #ifdef HAVE_return
7510 if (optimize && HAVE_return)
7512 /* If we're allowed to generate a simple return instruction,
7513 then by definition we don't need a full epilogue. Examine
7514 the block that falls through to EXIT. If it does not
7515 contain any code, examine its predecessors and try to
7516 emit (conditional) return instructions. */
7518 basic_block last;
7519 edge e_next;
7520 rtx label;
7522 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7523 if (e->flags & EDGE_FALLTHRU)
7524 break;
7525 if (e == NULL)
7526 goto epilogue_done;
7527 last = e->src;
7529 /* Verify that there are no active instructions in the last block. */
7530 label = last->end;
7531 while (label && GET_CODE (label) != CODE_LABEL)
7533 if (active_insn_p (label))
7534 break;
7535 label = PREV_INSN (label);
7538 if (last->head == label && GET_CODE (label) == CODE_LABEL)
7540 rtx epilogue_line_note = NULL_RTX;
7542 /* Locate the line number associated with the closing brace,
7543 if we can find one. */
7544 for (seq = get_last_insn ();
7545 seq && ! active_insn_p (seq);
7546 seq = PREV_INSN (seq))
7547 if (GET_CODE (seq) == NOTE && NOTE_LINE_NUMBER (seq) > 0)
7549 epilogue_line_note = seq;
7550 break;
7553 for (e = last->pred; e; e = e_next)
7555 basic_block bb = e->src;
7556 rtx jump;
7558 e_next = e->pred_next;
7559 if (bb == ENTRY_BLOCK_PTR)
7560 continue;
7562 jump = bb->end;
7563 if ((GET_CODE (jump) != JUMP_INSN) || JUMP_LABEL (jump) != label)
7564 continue;
7566 /* If we have an unconditional jump, we can replace that
7567 with a simple return instruction. */
7568 if (simplejump_p (jump))
7570 emit_return_into_block (bb, epilogue_line_note);
7571 delete_insn (jump);
7574 /* If we have a conditional jump, we can try to replace
7575 that with a conditional return instruction. */
7576 else if (condjump_p (jump))
7578 rtx ret, *loc;
7580 ret = SET_SRC (PATTERN (jump));
7581 if (GET_CODE (XEXP (ret, 1)) == LABEL_REF)
7582 loc = &XEXP (ret, 1);
7583 else
7584 loc = &XEXP (ret, 2);
7585 ret = gen_rtx_RETURN (VOIDmode);
7587 if (! validate_change (jump, loc, ret, 0))
7588 continue;
7589 if (JUMP_LABEL (jump))
7590 LABEL_NUSES (JUMP_LABEL (jump))--;
7592 /* If this block has only one successor, it both jumps
7593 and falls through to the fallthru block, so we can't
7594 delete the edge. */
7595 if (bb->succ->succ_next == NULL)
7596 continue;
7598 else
7599 continue;
7601 /* Fix up the CFG for the successful change we just made. */
7602 redirect_edge_succ (e, EXIT_BLOCK_PTR);
7605 /* Emit a return insn for the exit fallthru block. Whether
7606 this is still reachable will be determined later. */
7608 emit_barrier_after (last->end);
7609 emit_return_into_block (last, epilogue_line_note);
7610 epilogue_end = last->end;
7611 last->succ->flags &= ~EDGE_FALLTHRU;
7612 goto epilogue_done;
7615 #endif
7616 #ifdef HAVE_epilogue
7617 if (HAVE_epilogue)
7619 /* Find the edge that falls through to EXIT. Other edges may exist
7620 due to RETURN instructions, but those don't need epilogues.
7621 There really shouldn't be a mixture -- either all should have
7622 been converted or none, however... */
7624 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7625 if (e->flags & EDGE_FALLTHRU)
7626 break;
7627 if (e == NULL)
7628 goto epilogue_done;
7630 start_sequence ();
7631 epilogue_end = emit_note (NULL, NOTE_INSN_EPILOGUE_BEG);
7633 seq = gen_epilogue ();
7635 #ifdef INCOMING_RETURN_ADDR_RTX
7636 /* If this function returns with the stack depressed and we can support
7637 it, massage the epilogue to actually do that. */
7638 if (TREE_CODE (TREE_TYPE (current_function_decl)) == FUNCTION_TYPE
7639 && TYPE_RETURNS_STACK_DEPRESSED (TREE_TYPE (current_function_decl)))
7640 seq = keep_stack_depressed (seq);
7641 #endif
7643 emit_jump_insn (seq);
7645 /* Retain a map of the epilogue insns. */
7646 record_insns (seq, &epilogue);
7648 seq = get_insns ();
7649 end_sequence ();
7651 insert_insn_on_edge (seq, e);
7652 inserted = 1;
7654 #endif
7655 epilogue_done:
7657 if (inserted)
7658 commit_edge_insertions ();
7660 #ifdef HAVE_sibcall_epilogue
7661 /* Emit sibling epilogues before any sibling call sites. */
7662 for (e = EXIT_BLOCK_PTR->pred; e; e = e->pred_next)
7664 basic_block bb = e->src;
7665 rtx insn = bb->end;
7666 rtx i;
7667 rtx newinsn;
7669 if (GET_CODE (insn) != CALL_INSN
7670 || ! SIBLING_CALL_P (insn))
7671 continue;
7673 start_sequence ();
7674 emit_insn (gen_sibcall_epilogue ());
7675 seq = get_insns ();
7676 end_sequence ();
7678 /* Retain a map of the epilogue insns. Used in life analysis to
7679 avoid getting rid of sibcall epilogue insns. Do this before we
7680 actually emit the sequence. */
7681 record_insns (seq, &sibcall_epilogue);
7683 i = PREV_INSN (insn);
7684 newinsn = emit_insn_before (seq, insn);
7686 #endif
7688 #ifdef HAVE_prologue
7689 if (prologue_end)
7691 rtx insn, prev;
7693 /* GDB handles `break f' by setting a breakpoint on the first
7694 line note after the prologue. Which means (1) that if
7695 there are line number notes before where we inserted the
7696 prologue we should move them, and (2) we should generate a
7697 note before the end of the first basic block, if there isn't
7698 one already there.
7700 ??? This behavior is completely broken when dealing with
7701 multiple entry functions. We simply place the note always
7702 into first basic block and let alternate entry points
7703 to be missed.
7706 for (insn = prologue_end; insn; insn = prev)
7708 prev = PREV_INSN (insn);
7709 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7711 /* Note that we cannot reorder the first insn in the
7712 chain, since rest_of_compilation relies on that
7713 remaining constant. */
7714 if (prev == NULL)
7715 break;
7716 reorder_insns (insn, insn, prologue_end);
7720 /* Find the last line number note in the first block. */
7721 for (insn = ENTRY_BLOCK_PTR->next_bb->end;
7722 insn != prologue_end && insn;
7723 insn = PREV_INSN (insn))
7724 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7725 break;
7727 /* If we didn't find one, make a copy of the first line number
7728 we run across. */
7729 if (! insn)
7731 for (insn = next_active_insn (prologue_end);
7732 insn;
7733 insn = PREV_INSN (insn))
7734 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7736 emit_line_note_after (NOTE_SOURCE_FILE (insn),
7737 NOTE_LINE_NUMBER (insn),
7738 prologue_end);
7739 break;
7743 #endif
7744 #ifdef HAVE_epilogue
7745 if (epilogue_end)
7747 rtx insn, next;
7749 /* Similarly, move any line notes that appear after the epilogue.
7750 There is no need, however, to be quite so anal about the existence
7751 of such a note. */
7752 for (insn = epilogue_end; insn; insn = next)
7754 next = NEXT_INSN (insn);
7755 if (GET_CODE (insn) == NOTE && NOTE_LINE_NUMBER (insn) > 0)
7756 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
7759 #endif
7762 /* Reposition the prologue-end and epilogue-begin notes after instruction
7763 scheduling and delayed branch scheduling. */
7765 void
7766 reposition_prologue_and_epilogue_notes (f)
7767 rtx f ATTRIBUTE_UNUSED;
7769 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
7770 rtx insn, last, note;
7771 int len;
7773 if ((len = VARRAY_SIZE (prologue)) > 0)
7775 last = 0, note = 0;
7777 /* Scan from the beginning until we reach the last prologue insn.
7778 We apparently can't depend on basic_block_{head,end} after
7779 reorg has run. */
7780 for (insn = f; insn; insn = NEXT_INSN (insn))
7782 if (GET_CODE (insn) == NOTE)
7784 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PROLOGUE_END)
7785 note = insn;
7787 else if (contains (insn, prologue))
7789 last = insn;
7790 if (--len == 0)
7791 break;
7795 if (last)
7797 /* Find the prologue-end note if we haven't already, and
7798 move it to just after the last prologue insn. */
7799 if (note == 0)
7801 for (note = last; (note = NEXT_INSN (note));)
7802 if (GET_CODE (note) == NOTE
7803 && NOTE_LINE_NUMBER (note) == NOTE_INSN_PROLOGUE_END)
7804 break;
7807 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
7808 if (GET_CODE (last) == CODE_LABEL)
7809 last = NEXT_INSN (last);
7810 reorder_insns (note, note, last);
7814 if ((len = VARRAY_SIZE (epilogue)) > 0)
7816 last = 0, note = 0;
7818 /* Scan from the end until we reach the first epilogue insn.
7819 We apparently can't depend on basic_block_{head,end} after
7820 reorg has run. */
7821 for (insn = get_last_insn (); insn; insn = PREV_INSN (insn))
7823 if (GET_CODE (insn) == NOTE)
7825 if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EPILOGUE_BEG)
7826 note = insn;
7828 else if (contains (insn, epilogue))
7830 last = insn;
7831 if (--len == 0)
7832 break;
7836 if (last)
7838 /* Find the epilogue-begin note if we haven't already, and
7839 move it to just before the first epilogue insn. */
7840 if (note == 0)
7842 for (note = insn; (note = PREV_INSN (note));)
7843 if (GET_CODE (note) == NOTE
7844 && NOTE_LINE_NUMBER (note) == NOTE_INSN_EPILOGUE_BEG)
7845 break;
7848 if (PREV_INSN (last) != note)
7849 reorder_insns (note, note, PREV_INSN (last));
7852 #endif /* HAVE_prologue or HAVE_epilogue */
7855 /* Called once, at initialization, to initialize function.c. */
7857 void
7858 init_function_once ()
7860 VARRAY_INT_INIT (prologue, 0, "prologue");
7861 VARRAY_INT_INIT (epilogue, 0, "epilogue");
7862 VARRAY_INT_INIT (sibcall_epilogue, 0, "sibcall_epilogue");
7865 #include "gt-function.h"