1 /* Variable tracking routines for the GNU compiler.
2 Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it
7 under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GCC is distributed in the hope that it will be useful, but WITHOUT
12 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
13 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
14 License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING. If not, write to the Free
18 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
21 /* This file contains the variable tracking pass. It computes where
22 variables are located (which registers or where in memory) at each position
23 in instruction stream and emits notes describing the locations.
24 Debug information (DWARF2 location lists) is finally generated from
26 With this debug information, it is possible to show variables
27 even when debugging optimized code.
29 How does the variable tracking pass work?
31 First, it scans RTL code for uses, stores and clobbers (register/memory
32 references in instructions), for call insns and for stack adjustments
33 separately for each basic block and saves them to an array of micro
35 The micro operations of one instruction are ordered so that
36 pre-modifying stack adjustment < use < use with no var < call insn <
37 < set < clobber < post-modifying stack adjustment
39 Then, a forward dataflow analysis is performed to find out how locations
40 of variables change through code and to propagate the variable locations
41 along control flow graph.
42 The IN set for basic block BB is computed as a union of OUT sets of BB's
43 predecessors, the OUT set for BB is copied from the IN set for BB and
44 is changed according to micro operations in BB.
46 The IN and OUT sets for basic blocks consist of a current stack adjustment
47 (used for adjusting offset of variables addressed using stack pointer),
48 the table of structures describing the locations of parts of a variable
49 and for each physical register a linked list for each physical register.
50 The linked list is a list of variable parts stored in the register,
51 i.e. it is a list of triplets (reg, decl, offset) where decl is
52 REG_EXPR (reg) and offset is REG_OFFSET (reg). The linked list is used for
53 effective deleting appropriate variable parts when we set or clobber the
56 There may be more than one variable part in a register. The linked lists
57 should be pretty short so it is a good data structure here.
58 For example in the following code, register allocator may assign same
59 register to variables A and B, and both of them are stored in the same
72 Finally, the NOTE_INSN_VAR_LOCATION notes describing the variable locations
73 are emitted to appropriate positions in RTL code. Each such a note describes
74 the location of one variable at the point in instruction stream where the
75 note is. There is no need to emit a note for each variable before each
76 instruction, we only emit these notes where the location of variable changes
77 (this means that we also emit notes for changes between the OUT set of the
78 previous block and the IN set of the current block).
80 The notes consist of two parts:
81 1. the declaration (from REG_EXPR or MEM_EXPR)
82 2. the location of a variable - it is either a simple register/memory
83 reference (for simple variables, for example int),
84 or a parallel of register/memory references (for a large variables
85 which consist of several parts, for example long long).
91 #include "coretypes.h"
95 #include "hard-reg-set.h"
96 #include "basic-block.h"
99 #include "insn-config.h"
102 #include "alloc-pool.h"
108 #include "tree-pass.h"
110 /* Type of micro operation. */
111 enum micro_operation_type
113 MO_USE, /* Use location (REG or MEM). */
114 MO_USE_NO_VAR,/* Use location which is not associated with a variable
115 or the variable is not trackable. */
116 MO_SET, /* Set location. */
117 MO_COPY, /* Copy the same portion of a variable from one
118 location to another. */
119 MO_CLOBBER, /* Clobber location. */
120 MO_CALL, /* Call insn. */
121 MO_ADJUST /* Adjust stack pointer. */
124 /* Where shall the note be emitted? BEFORE or AFTER the instruction. */
127 EMIT_NOTE_BEFORE_INSN,
131 /* Structure holding information about micro operation. */
132 typedef struct micro_operation_def
134 /* Type of micro operation. */
135 enum micro_operation_type type;
141 /* Stack adjustment. */
142 HOST_WIDE_INT adjust;
145 /* The instruction which the micro operation is in, for MO_USE,
146 MO_USE_NO_VAR, MO_CALL and MO_ADJUST, or the subsequent
147 instruction or note in the original flow (before any var-tracking
148 notes are inserted, to simplify emission of notes), for MO_SET
153 /* Structure for passing some other parameters to function
154 emit_note_insn_var_location. */
155 typedef struct emit_note_data_def
157 /* The instruction which the note will be emitted before/after. */
160 /* Where the note will be emitted (before/after insn)? */
161 enum emit_note_where where;
164 /* Description of location of a part of a variable. The content of a physical
165 register is described by a chain of these structures.
166 The chains are pretty short (usually 1 or 2 elements) and thus
167 chain is the best data structure. */
168 typedef struct attrs_def
170 /* Pointer to next member of the list. */
171 struct attrs_def *next;
173 /* The rtx of register. */
176 /* The declaration corresponding to LOC. */
179 /* Offset from start of DECL. */
180 HOST_WIDE_INT offset;
183 /* Structure holding the IN or OUT set for a basic block. */
184 typedef struct dataflow_set_def
186 /* Adjustment of stack offset. */
187 HOST_WIDE_INT stack_adjust;
189 /* Attributes for registers (lists of attrs). */
190 attrs regs[FIRST_PSEUDO_REGISTER];
192 /* Variable locations. */
196 /* The structure (one for each basic block) containing the information
197 needed for variable tracking. */
198 typedef struct variable_tracking_info_def
200 /* Number of micro operations stored in the MOS array. */
203 /* The array of micro operations. */
204 micro_operation *mos;
206 /* The IN and OUT set for dataflow analysis. */
210 /* Has the block been visited in DFS? */
212 } *variable_tracking_info;
214 /* Structure for chaining the locations. */
215 typedef struct location_chain_def
217 /* Next element in the chain. */
218 struct location_chain_def *next;
220 /* The location (REG or MEM). */
224 /* Structure describing one part of variable. */
225 typedef struct variable_part_def
227 /* Chain of locations of the part. */
228 location_chain loc_chain;
230 /* Location which was last emitted to location list. */
233 /* The offset in the variable. */
234 HOST_WIDE_INT offset;
237 /* Maximum number of location parts. */
238 #define MAX_VAR_PARTS 16
240 /* Structure describing where the variable is located. */
241 typedef struct variable_def
243 /* The declaration of the variable. */
246 /* Reference count. */
249 /* Number of variable parts. */
252 /* The variable parts. */
253 variable_part var_part[MAX_VAR_PARTS];
256 /* Hash function for DECL for VARIABLE_HTAB. */
257 #define VARIABLE_HASH_VAL(decl) (DECL_UID (decl))
259 /* Pointer to the BB's information specific to variable tracking pass. */
260 #define VTI(BB) ((variable_tracking_info) (BB)->aux)
262 /* Macro to access MEM_OFFSET as an HOST_WIDE_INT. Evaluates MEM twice. */
263 #define INT_MEM_OFFSET(mem) (MEM_OFFSET (mem) ? INTVAL (MEM_OFFSET (mem)) : 0)
265 /* Alloc pool for struct attrs_def. */
266 static alloc_pool attrs_pool;
268 /* Alloc pool for struct variable_def. */
269 static alloc_pool var_pool;
271 /* Alloc pool for struct location_chain_def. */
272 static alloc_pool loc_chain_pool;
274 /* Changed variables, notes will be emitted for them. */
275 static htab_t changed_variables;
277 /* Shall notes be emitted? */
278 static bool emit_notes;
280 /* Local function prototypes. */
281 static void stack_adjust_offset_pre_post (rtx, HOST_WIDE_INT *,
283 static void insn_stack_adjust_offset_pre_post (rtx, HOST_WIDE_INT *,
285 static void bb_stack_adjust_offset (basic_block);
286 static bool vt_stack_adjustments (void);
287 static rtx adjust_stack_reference (rtx, HOST_WIDE_INT);
288 static hashval_t variable_htab_hash (const void *);
289 static int variable_htab_eq (const void *, const void *);
290 static void variable_htab_free (void *);
292 static void init_attrs_list_set (attrs *);
293 static void attrs_list_clear (attrs *);
294 static attrs attrs_list_member (attrs, tree, HOST_WIDE_INT);
295 static void attrs_list_insert (attrs *, tree, HOST_WIDE_INT, rtx);
296 static void attrs_list_copy (attrs *, attrs);
297 static void attrs_list_union (attrs *, attrs);
299 static void vars_clear (htab_t);
300 static variable unshare_variable (dataflow_set *set, variable var);
301 static int vars_copy_1 (void **, void *);
302 static void vars_copy (htab_t, htab_t);
303 static tree var_debug_decl (tree);
304 static void var_reg_set (dataflow_set *, rtx);
305 static void var_reg_delete_and_set (dataflow_set *, rtx, bool);
306 static void var_reg_delete (dataflow_set *, rtx, bool);
307 static void var_regno_delete (dataflow_set *, int);
308 static void var_mem_set (dataflow_set *, rtx);
309 static void var_mem_delete_and_set (dataflow_set *, rtx, bool);
310 static void var_mem_delete (dataflow_set *, rtx, bool);
312 static void dataflow_set_init (dataflow_set *, int);
313 static void dataflow_set_clear (dataflow_set *);
314 static void dataflow_set_copy (dataflow_set *, dataflow_set *);
315 static int variable_union_info_cmp_pos (const void *, const void *);
316 static int variable_union (void **, void *);
317 static void dataflow_set_union (dataflow_set *, dataflow_set *);
318 static bool variable_part_different_p (variable_part *, variable_part *);
319 static bool variable_different_p (variable, variable, bool);
320 static int dataflow_set_different_1 (void **, void *);
321 static int dataflow_set_different_2 (void **, void *);
322 static bool dataflow_set_different (dataflow_set *, dataflow_set *);
323 static void dataflow_set_destroy (dataflow_set *);
325 static bool contains_symbol_ref (rtx);
326 static bool track_expr_p (tree);
327 static bool same_variable_part_p (rtx, tree, HOST_WIDE_INT);
328 static int count_uses (rtx *, void *);
329 static void count_uses_1 (rtx *, void *);
330 static void count_stores (rtx, rtx, void *);
331 static int add_uses (rtx *, void *);
332 static void add_uses_1 (rtx *, void *);
333 static void add_stores (rtx, rtx, void *);
334 static bool compute_bb_dataflow (basic_block);
335 static void vt_find_locations (void);
337 static void dump_attrs_list (attrs);
338 static int dump_variable (void **, void *);
339 static void dump_vars (htab_t);
340 static void dump_dataflow_set (dataflow_set *);
341 static void dump_dataflow_sets (void);
343 static void variable_was_changed (variable, htab_t);
344 static void set_variable_part (dataflow_set *, rtx, tree, HOST_WIDE_INT);
345 static void clobber_variable_part (dataflow_set *, rtx, tree, HOST_WIDE_INT);
346 static void delete_variable_part (dataflow_set *, rtx, tree, HOST_WIDE_INT);
347 static int emit_note_insn_var_location (void **, void *);
348 static void emit_notes_for_changes (rtx, enum emit_note_where);
349 static int emit_notes_for_differences_1 (void **, void *);
350 static int emit_notes_for_differences_2 (void **, void *);
351 static void emit_notes_for_differences (rtx, dataflow_set *, dataflow_set *);
352 static void emit_notes_in_bb (basic_block);
353 static void vt_emit_notes (void);
355 static bool vt_get_decl_and_offset (rtx, tree *, HOST_WIDE_INT *);
356 static void vt_add_function_parameters (void);
357 static void vt_initialize (void);
358 static void vt_finalize (void);
360 /* Given a SET, calculate the amount of stack adjustment it contains
361 PRE- and POST-modifying stack pointer.
362 This function is similar to stack_adjust_offset. */
365 stack_adjust_offset_pre_post (rtx pattern, HOST_WIDE_INT *pre,
368 rtx src = SET_SRC (pattern);
369 rtx dest = SET_DEST (pattern);
372 if (dest == stack_pointer_rtx)
374 /* (set (reg sp) (plus (reg sp) (const_int))) */
375 code = GET_CODE (src);
376 if (! (code == PLUS || code == MINUS)
377 || XEXP (src, 0) != stack_pointer_rtx
378 || GET_CODE (XEXP (src, 1)) != CONST_INT)
382 *post += INTVAL (XEXP (src, 1));
384 *post -= INTVAL (XEXP (src, 1));
386 else if (MEM_P (dest))
388 /* (set (mem (pre_dec (reg sp))) (foo)) */
389 src = XEXP (dest, 0);
390 code = GET_CODE (src);
396 if (XEXP (src, 0) == stack_pointer_rtx)
398 rtx val = XEXP (XEXP (src, 1), 1);
399 /* We handle only adjustments by constant amount. */
400 gcc_assert (GET_CODE (XEXP (src, 1)) == PLUS &&
401 GET_CODE (val) == CONST_INT);
403 if (code == PRE_MODIFY)
404 *pre -= INTVAL (val);
406 *post -= INTVAL (val);
412 if (XEXP (src, 0) == stack_pointer_rtx)
414 *pre += GET_MODE_SIZE (GET_MODE (dest));
420 if (XEXP (src, 0) == stack_pointer_rtx)
422 *post += GET_MODE_SIZE (GET_MODE (dest));
428 if (XEXP (src, 0) == stack_pointer_rtx)
430 *pre -= GET_MODE_SIZE (GET_MODE (dest));
436 if (XEXP (src, 0) == stack_pointer_rtx)
438 *post -= GET_MODE_SIZE (GET_MODE (dest));
449 /* Given an INSN, calculate the amount of stack adjustment it contains
450 PRE- and POST-modifying stack pointer. */
453 insn_stack_adjust_offset_pre_post (rtx insn, HOST_WIDE_INT *pre,
459 if (GET_CODE (PATTERN (insn)) == SET)
460 stack_adjust_offset_pre_post (PATTERN (insn), pre, post);
461 else if (GET_CODE (PATTERN (insn)) == PARALLEL
462 || GET_CODE (PATTERN (insn)) == SEQUENCE)
466 /* There may be stack adjustments inside compound insns. Search
468 for ( i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
469 if (GET_CODE (XVECEXP (PATTERN (insn), 0, i)) == SET)
470 stack_adjust_offset_pre_post (XVECEXP (PATTERN (insn), 0, i),
475 /* Compute stack adjustment in basic block BB. */
478 bb_stack_adjust_offset (basic_block bb)
480 HOST_WIDE_INT offset;
483 offset = VTI (bb)->in.stack_adjust;
484 for (i = 0; i < VTI (bb)->n_mos; i++)
486 if (VTI (bb)->mos[i].type == MO_ADJUST)
487 offset += VTI (bb)->mos[i].u.adjust;
488 else if (VTI (bb)->mos[i].type != MO_CALL)
490 if (MEM_P (VTI (bb)->mos[i].u.loc))
492 VTI (bb)->mos[i].u.loc
493 = adjust_stack_reference (VTI (bb)->mos[i].u.loc, -offset);
497 VTI (bb)->out.stack_adjust = offset;
500 /* Compute stack adjustments for all blocks by traversing DFS tree.
501 Return true when the adjustments on all incoming edges are consistent.
502 Heavily borrowed from pre_and_rev_post_order_compute. */
505 vt_stack_adjustments (void)
507 edge_iterator *stack;
510 /* Initialize entry block. */
511 VTI (ENTRY_BLOCK_PTR)->visited = true;
512 VTI (ENTRY_BLOCK_PTR)->out.stack_adjust = INCOMING_FRAME_SP_OFFSET;
514 /* Allocate stack for back-tracking up CFG. */
515 stack = XNEWVEC (edge_iterator, n_basic_blocks + 1);
518 /* Push the first edge on to the stack. */
519 stack[sp++] = ei_start (ENTRY_BLOCK_PTR->succs);
527 /* Look at the edge on the top of the stack. */
529 src = ei_edge (ei)->src;
530 dest = ei_edge (ei)->dest;
532 /* Check if the edge destination has been visited yet. */
533 if (!VTI (dest)->visited)
535 VTI (dest)->visited = true;
536 VTI (dest)->in.stack_adjust = VTI (src)->out.stack_adjust;
537 bb_stack_adjust_offset (dest);
539 if (EDGE_COUNT (dest->succs) > 0)
540 /* Since the DEST node has been visited for the first
541 time, check its successors. */
542 stack[sp++] = ei_start (dest->succs);
546 /* Check whether the adjustments on the edges are the same. */
547 if (VTI (dest)->in.stack_adjust != VTI (src)->out.stack_adjust)
553 if (! ei_one_before_end_p (ei))
554 /* Go to the next edge. */
555 ei_next (&stack[sp - 1]);
557 /* Return to previous level if there are no more edges. */
566 /* Adjust stack reference MEM by ADJUSTMENT bytes and make it relative
567 to the argument pointer. Return the new rtx. */
570 adjust_stack_reference (rtx mem, HOST_WIDE_INT adjustment)
574 #ifdef FRAME_POINTER_CFA_OFFSET
575 adjustment -= FRAME_POINTER_CFA_OFFSET (current_function_decl);
576 cfa = plus_constant (frame_pointer_rtx, adjustment);
578 adjustment -= ARG_POINTER_CFA_OFFSET (current_function_decl);
579 cfa = plus_constant (arg_pointer_rtx, adjustment);
582 addr = replace_rtx (copy_rtx (XEXP (mem, 0)), stack_pointer_rtx, cfa);
583 tmp = simplify_rtx (addr);
587 return replace_equiv_address_nv (mem, addr);
590 /* The hash function for variable_htab, computes the hash value
591 from the declaration of variable X. */
594 variable_htab_hash (const void *x)
596 const variable v = (const variable) x;
598 return (VARIABLE_HASH_VAL (v->decl));
601 /* Compare the declaration of variable X with declaration Y. */
604 variable_htab_eq (const void *x, const void *y)
606 const variable v = (const variable) x;
607 const tree decl = (const tree) y;
609 return (VARIABLE_HASH_VAL (v->decl) == VARIABLE_HASH_VAL (decl));
612 /* Free the element of VARIABLE_HTAB (its type is struct variable_def). */
615 variable_htab_free (void *elem)
618 variable var = (variable) elem;
619 location_chain node, next;
621 gcc_assert (var->refcount > 0);
624 if (var->refcount > 0)
627 for (i = 0; i < var->n_var_parts; i++)
629 for (node = var->var_part[i].loc_chain; node; node = next)
632 pool_free (loc_chain_pool, node);
634 var->var_part[i].loc_chain = NULL;
636 pool_free (var_pool, var);
639 /* Initialize the set (array) SET of attrs to empty lists. */
642 init_attrs_list_set (attrs *set)
646 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
650 /* Make the list *LISTP empty. */
653 attrs_list_clear (attrs *listp)
657 for (list = *listp; list; list = next)
660 pool_free (attrs_pool, list);
665 /* Return true if the pair of DECL and OFFSET is the member of the LIST. */
668 attrs_list_member (attrs list, tree decl, HOST_WIDE_INT offset)
670 for (; list; list = list->next)
671 if (list->decl == decl && list->offset == offset)
676 /* Insert the triplet DECL, OFFSET, LOC to the list *LISTP. */
679 attrs_list_insert (attrs *listp, tree decl, HOST_WIDE_INT offset, rtx loc)
683 list = pool_alloc (attrs_pool);
686 list->offset = offset;
691 /* Copy all nodes from SRC and create a list *DSTP of the copies. */
694 attrs_list_copy (attrs *dstp, attrs src)
698 attrs_list_clear (dstp);
699 for (; src; src = src->next)
701 n = pool_alloc (attrs_pool);
704 n->offset = src->offset;
710 /* Add all nodes from SRC which are not in *DSTP to *DSTP. */
713 attrs_list_union (attrs *dstp, attrs src)
715 for (; src; src = src->next)
717 if (!attrs_list_member (*dstp, src->decl, src->offset))
718 attrs_list_insert (dstp, src->decl, src->offset, src->loc);
722 /* Delete all variables from hash table VARS. */
725 vars_clear (htab_t vars)
730 /* Return a copy of a variable VAR and insert it to dataflow set SET. */
733 unshare_variable (dataflow_set *set, variable var)
739 new_var = pool_alloc (var_pool);
740 new_var->decl = var->decl;
741 new_var->refcount = 1;
743 new_var->n_var_parts = var->n_var_parts;
745 for (i = 0; i < var->n_var_parts; i++)
748 location_chain *nextp;
750 new_var->var_part[i].offset = var->var_part[i].offset;
751 nextp = &new_var->var_part[i].loc_chain;
752 for (node = var->var_part[i].loc_chain; node; node = node->next)
754 location_chain new_lc;
756 new_lc = pool_alloc (loc_chain_pool);
758 new_lc->loc = node->loc;
761 nextp = &new_lc->next;
764 /* We are at the basic block boundary when copying variable description
765 so set the CUR_LOC to be the first element of the chain. */
766 if (new_var->var_part[i].loc_chain)
767 new_var->var_part[i].cur_loc = new_var->var_part[i].loc_chain->loc;
769 new_var->var_part[i].cur_loc = NULL;
772 slot = htab_find_slot_with_hash (set->vars, new_var->decl,
773 VARIABLE_HASH_VAL (new_var->decl),
779 /* Add a variable from *SLOT to hash table DATA and increase its reference
783 vars_copy_1 (void **slot, void *data)
785 htab_t dst = (htab_t) data;
788 src = *(variable *) slot;
791 dstp = (variable *) htab_find_slot_with_hash (dst, src->decl,
792 VARIABLE_HASH_VAL (src->decl),
796 /* Continue traversing the hash table. */
800 /* Copy all variables from hash table SRC to hash table DST. */
803 vars_copy (htab_t dst, htab_t src)
806 htab_traverse (src, vars_copy_1, dst);
809 /* Map a decl to its main debug decl. */
812 var_debug_decl (tree decl)
814 if (decl && DECL_P (decl)
815 && DECL_DEBUG_EXPR_IS_FROM (decl) && DECL_DEBUG_EXPR (decl)
816 && DECL_P (DECL_DEBUG_EXPR (decl)))
817 decl = DECL_DEBUG_EXPR (decl);
822 /* Set the register to contain REG_EXPR (LOC), REG_OFFSET (LOC). */
825 var_reg_set (dataflow_set *set, rtx loc)
827 tree decl = REG_EXPR (loc);
828 HOST_WIDE_INT offset = REG_OFFSET (loc);
831 decl = var_debug_decl (decl);
833 for (node = set->regs[REGNO (loc)]; node; node = node->next)
834 if (node->decl == decl && node->offset == offset)
837 attrs_list_insert (&set->regs[REGNO (loc)], decl, offset, loc);
838 set_variable_part (set, loc, decl, offset);
841 /* Delete current content of register LOC in dataflow set SET and set
842 the register to contain REG_EXPR (LOC), REG_OFFSET (LOC). If
843 MODIFY is true, any other live copies of the same variable part are
844 also deleted from the dataflow set, otherwise the variable part is
845 assumed to be copied from another location holding the same
849 var_reg_delete_and_set (dataflow_set *set, rtx loc, bool modify)
851 tree decl = REG_EXPR (loc);
852 HOST_WIDE_INT offset = REG_OFFSET (loc);
856 decl = var_debug_decl (decl);
858 nextp = &set->regs[REGNO (loc)];
859 for (node = *nextp; node; node = next)
862 if (node->decl != decl || node->offset != offset)
864 delete_variable_part (set, node->loc, node->decl, node->offset);
865 pool_free (attrs_pool, node);
875 clobber_variable_part (set, loc, decl, offset);
876 var_reg_set (set, loc);
879 /* Delete current content of register LOC in dataflow set SET. If
880 CLOBBER is true, also delete any other live copies of the same
884 var_reg_delete (dataflow_set *set, rtx loc, bool clobber)
886 attrs *reg = &set->regs[REGNO (loc)];
891 tree decl = REG_EXPR (loc);
892 HOST_WIDE_INT offset = REG_OFFSET (loc);
894 decl = var_debug_decl (decl);
896 clobber_variable_part (set, NULL, decl, offset);
899 for (node = *reg; node; node = next)
902 delete_variable_part (set, node->loc, node->decl, node->offset);
903 pool_free (attrs_pool, node);
908 /* Delete content of register with number REGNO in dataflow set SET. */
911 var_regno_delete (dataflow_set *set, int regno)
913 attrs *reg = &set->regs[regno];
916 for (node = *reg; node; node = next)
919 delete_variable_part (set, node->loc, node->decl, node->offset);
920 pool_free (attrs_pool, node);
925 /* Set the location part of variable MEM_EXPR (LOC) in dataflow set
927 Adjust the address first if it is stack pointer based. */
930 var_mem_set (dataflow_set *set, rtx loc)
932 tree decl = MEM_EXPR (loc);
933 HOST_WIDE_INT offset = INT_MEM_OFFSET (loc);
935 decl = var_debug_decl (decl);
937 set_variable_part (set, loc, decl, offset);
940 /* Delete and set the location part of variable MEM_EXPR (LOC) in
941 dataflow set SET to LOC. If MODIFY is true, any other live copies
942 of the same variable part are also deleted from the dataflow set,
943 otherwise the variable part is assumed to be copied from another
944 location holding the same part.
945 Adjust the address first if it is stack pointer based. */
948 var_mem_delete_and_set (dataflow_set *set, rtx loc, bool modify)
950 tree decl = MEM_EXPR (loc);
951 HOST_WIDE_INT offset = INT_MEM_OFFSET (loc);
953 decl = var_debug_decl (decl);
956 clobber_variable_part (set, NULL, decl, offset);
957 var_mem_set (set, loc);
960 /* Delete the location part LOC from dataflow set SET. If CLOBBER is
961 true, also delete any other live copies of the same variable part.
962 Adjust the address first if it is stack pointer based. */
965 var_mem_delete (dataflow_set *set, rtx loc, bool clobber)
967 tree decl = MEM_EXPR (loc);
968 HOST_WIDE_INT offset = INT_MEM_OFFSET (loc);
970 decl = var_debug_decl (decl);
972 clobber_variable_part (set, NULL, decl, offset);
973 delete_variable_part (set, loc, decl, offset);
976 /* Initialize dataflow set SET to be empty.
977 VARS_SIZE is the initial size of hash table VARS. */
980 dataflow_set_init (dataflow_set *set, int vars_size)
982 init_attrs_list_set (set->regs);
983 set->vars = htab_create (vars_size, variable_htab_hash, variable_htab_eq,
985 set->stack_adjust = 0;
988 /* Delete the contents of dataflow set SET. */
991 dataflow_set_clear (dataflow_set *set)
995 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
996 attrs_list_clear (&set->regs[i]);
998 vars_clear (set->vars);
1001 /* Copy the contents of dataflow set SRC to DST. */
1004 dataflow_set_copy (dataflow_set *dst, dataflow_set *src)
1008 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
1009 attrs_list_copy (&dst->regs[i], src->regs[i]);
1011 vars_copy (dst->vars, src->vars);
1012 dst->stack_adjust = src->stack_adjust;
1015 /* Information for merging lists of locations for a given offset of variable.
1017 struct variable_union_info
1019 /* Node of the location chain. */
1022 /* The sum of positions in the input chains. */
1025 /* The position in the chains of SRC and DST dataflow sets. */
1030 /* Compare function for qsort, order the structures by POS element. */
1033 variable_union_info_cmp_pos (const void *n1, const void *n2)
1035 const struct variable_union_info *i1 = n1;
1036 const struct variable_union_info *i2 = n2;
1038 if (i1->pos != i2->pos)
1039 return i1->pos - i2->pos;
1041 return (i1->pos_dst - i2->pos_dst);
1044 /* Compute union of location parts of variable *SLOT and the same variable
1045 from hash table DATA. Compute "sorted" union of the location chains
1046 for common offsets, i.e. the locations of a variable part are sorted by
1047 a priority where the priority is the sum of the positions in the 2 chains
1048 (if a location is only in one list the position in the second list is
1049 defined to be larger than the length of the chains).
1050 When we are updating the location parts the newest location is in the
1051 beginning of the chain, so when we do the described "sorted" union
1052 we keep the newest locations in the beginning. */
1055 variable_union (void **slot, void *data)
1057 variable src, dst, *dstp;
1058 dataflow_set *set = (dataflow_set *) data;
1061 src = *(variable *) slot;
1062 dstp = (variable *) htab_find_slot_with_hash (set->vars, src->decl,
1063 VARIABLE_HASH_VAL (src->decl),
1069 /* If CUR_LOC of some variable part is not the first element of
1070 the location chain we are going to change it so we have to make
1071 a copy of the variable. */
1072 for (k = 0; k < src->n_var_parts; k++)
1074 gcc_assert (!src->var_part[k].loc_chain
1075 == !src->var_part[k].cur_loc);
1076 if (src->var_part[k].loc_chain)
1078 gcc_assert (src->var_part[k].cur_loc);
1079 if (src->var_part[k].cur_loc != src->var_part[k].loc_chain->loc)
1083 if (k < src->n_var_parts)
1084 unshare_variable (set, src);
1088 /* Continue traversing the hash table. */
1094 gcc_assert (src->n_var_parts);
1096 /* Count the number of location parts, result is K. */
1097 for (i = 0, j = 0, k = 0;
1098 i < src->n_var_parts && j < dst->n_var_parts; k++)
1100 if (src->var_part[i].offset == dst->var_part[j].offset)
1105 else if (src->var_part[i].offset < dst->var_part[j].offset)
1110 k += src->n_var_parts - i;
1111 k += dst->n_var_parts - j;
1113 /* We track only variables whose size is <= MAX_VAR_PARTS bytes
1114 thus there are at most MAX_VAR_PARTS different offsets. */
1115 gcc_assert (k <= MAX_VAR_PARTS);
1117 if (dst->refcount > 1 && dst->n_var_parts != k)
1118 dst = unshare_variable (set, dst);
1120 i = src->n_var_parts - 1;
1121 j = dst->n_var_parts - 1;
1122 dst->n_var_parts = k;
1124 for (k--; k >= 0; k--)
1126 location_chain node, node2;
1128 if (i >= 0 && j >= 0
1129 && src->var_part[i].offset == dst->var_part[j].offset)
1131 /* Compute the "sorted" union of the chains, i.e. the locations which
1132 are in both chains go first, they are sorted by the sum of
1133 positions in the chains. */
1136 struct variable_union_info *vui;
1138 /* If DST is shared compare the location chains.
1139 If they are different we will modify the chain in DST with
1140 high probability so make a copy of DST. */
1141 if (dst->refcount > 1)
1143 for (node = src->var_part[i].loc_chain,
1144 node2 = dst->var_part[j].loc_chain; node && node2;
1145 node = node->next, node2 = node2->next)
1147 if (!((REG_P (node2->loc)
1148 && REG_P (node->loc)
1149 && REGNO (node2->loc) == REGNO (node->loc))
1150 || rtx_equal_p (node2->loc, node->loc)))
1154 dst = unshare_variable (set, dst);
1158 for (node = src->var_part[i].loc_chain; node; node = node->next)
1161 for (node = dst->var_part[j].loc_chain; node; node = node->next)
1163 vui = XCNEWVEC (struct variable_union_info, src_l + dst_l);
1165 /* Fill in the locations from DST. */
1166 for (node = dst->var_part[j].loc_chain, jj = 0; node;
1167 node = node->next, jj++)
1170 vui[jj].pos_dst = jj;
1172 /* Value larger than a sum of 2 valid positions. */
1173 vui[jj].pos_src = src_l + dst_l;
1176 /* Fill in the locations from SRC. */
1178 for (node = src->var_part[i].loc_chain, ii = 0; node;
1179 node = node->next, ii++)
1181 /* Find location from NODE. */
1182 for (jj = 0; jj < dst_l; jj++)
1184 if ((REG_P (vui[jj].lc->loc)
1185 && REG_P (node->loc)
1186 && REGNO (vui[jj].lc->loc) == REGNO (node->loc))
1187 || rtx_equal_p (vui[jj].lc->loc, node->loc))
1189 vui[jj].pos_src = ii;
1193 if (jj >= dst_l) /* The location has not been found. */
1195 location_chain new_node;
1197 /* Copy the location from SRC. */
1198 new_node = pool_alloc (loc_chain_pool);
1199 new_node->loc = node->loc;
1200 vui[n].lc = new_node;
1201 vui[n].pos_src = ii;
1202 vui[n].pos_dst = src_l + dst_l;
1207 for (ii = 0; ii < src_l + dst_l; ii++)
1208 vui[ii].pos = vui[ii].pos_src + vui[ii].pos_dst;
1210 qsort (vui, n, sizeof (struct variable_union_info),
1211 variable_union_info_cmp_pos);
1213 /* Reconnect the nodes in sorted order. */
1214 for (ii = 1; ii < n; ii++)
1215 vui[ii - 1].lc->next = vui[ii].lc;
1216 vui[n - 1].lc->next = NULL;
1218 dst->var_part[k].loc_chain = vui[0].lc;
1219 dst->var_part[k].offset = dst->var_part[j].offset;
1225 else if ((i >= 0 && j >= 0
1226 && src->var_part[i].offset < dst->var_part[j].offset)
1229 dst->var_part[k] = dst->var_part[j];
1232 else if ((i >= 0 && j >= 0
1233 && src->var_part[i].offset > dst->var_part[j].offset)
1236 location_chain *nextp;
1238 /* Copy the chain from SRC. */
1239 nextp = &dst->var_part[k].loc_chain;
1240 for (node = src->var_part[i].loc_chain; node; node = node->next)
1242 location_chain new_lc;
1244 new_lc = pool_alloc (loc_chain_pool);
1245 new_lc->next = NULL;
1246 new_lc->loc = node->loc;
1249 nextp = &new_lc->next;
1252 dst->var_part[k].offset = src->var_part[i].offset;
1256 /* We are at the basic block boundary when computing union
1257 so set the CUR_LOC to be the first element of the chain. */
1258 if (dst->var_part[k].loc_chain)
1259 dst->var_part[k].cur_loc = dst->var_part[k].loc_chain->loc;
1261 dst->var_part[k].cur_loc = NULL;
1264 /* Continue traversing the hash table. */
1268 /* Compute union of dataflow sets SRC and DST and store it to DST. */
1271 dataflow_set_union (dataflow_set *dst, dataflow_set *src)
1275 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
1276 attrs_list_union (&dst->regs[i], src->regs[i]);
1278 htab_traverse (src->vars, variable_union, dst);
1281 /* Flag whether two dataflow sets being compared contain different data. */
1283 dataflow_set_different_value;
1286 variable_part_different_p (variable_part *vp1, variable_part *vp2)
1288 location_chain lc1, lc2;
1290 for (lc1 = vp1->loc_chain; lc1; lc1 = lc1->next)
1292 for (lc2 = vp2->loc_chain; lc2; lc2 = lc2->next)
1294 if (REG_P (lc1->loc) && REG_P (lc2->loc))
1296 if (REGNO (lc1->loc) == REGNO (lc2->loc))
1299 if (rtx_equal_p (lc1->loc, lc2->loc))
1308 /* Return true if variables VAR1 and VAR2 are different.
1309 If COMPARE_CURRENT_LOCATION is true compare also the cur_loc of each
1313 variable_different_p (variable var1, variable var2,
1314 bool compare_current_location)
1321 if (var1->n_var_parts != var2->n_var_parts)
1324 for (i = 0; i < var1->n_var_parts; i++)
1326 if (var1->var_part[i].offset != var2->var_part[i].offset)
1328 if (compare_current_location)
1330 if (!((REG_P (var1->var_part[i].cur_loc)
1331 && REG_P (var2->var_part[i].cur_loc)
1332 && (REGNO (var1->var_part[i].cur_loc)
1333 == REGNO (var2->var_part[i].cur_loc)))
1334 || rtx_equal_p (var1->var_part[i].cur_loc,
1335 var2->var_part[i].cur_loc)))
1338 if (variable_part_different_p (&var1->var_part[i], &var2->var_part[i]))
1340 if (variable_part_different_p (&var2->var_part[i], &var1->var_part[i]))
1346 /* Compare variable *SLOT with the same variable in hash table DATA
1347 and set DATAFLOW_SET_DIFFERENT_VALUE if they are different. */
1350 dataflow_set_different_1 (void **slot, void *data)
1352 htab_t htab = (htab_t) data;
1353 variable var1, var2;
1355 var1 = *(variable *) slot;
1356 var2 = htab_find_with_hash (htab, var1->decl,
1357 VARIABLE_HASH_VAL (var1->decl));
1360 dataflow_set_different_value = true;
1362 /* Stop traversing the hash table. */
1366 if (variable_different_p (var1, var2, false))
1368 dataflow_set_different_value = true;
1370 /* Stop traversing the hash table. */
1374 /* Continue traversing the hash table. */
1378 /* Compare variable *SLOT with the same variable in hash table DATA
1379 and set DATAFLOW_SET_DIFFERENT_VALUE if they are different. */
1382 dataflow_set_different_2 (void **slot, void *data)
1384 htab_t htab = (htab_t) data;
1385 variable var1, var2;
1387 var1 = *(variable *) slot;
1388 var2 = htab_find_with_hash (htab, var1->decl,
1389 VARIABLE_HASH_VAL (var1->decl));
1392 dataflow_set_different_value = true;
1394 /* Stop traversing the hash table. */
1398 /* If both variables are defined they have been already checked for
1400 gcc_assert (!variable_different_p (var1, var2, false));
1402 /* Continue traversing the hash table. */
1406 /* Return true if dataflow sets OLD_SET and NEW_SET differ. */
1409 dataflow_set_different (dataflow_set *old_set, dataflow_set *new_set)
1411 dataflow_set_different_value = false;
1413 htab_traverse (old_set->vars, dataflow_set_different_1, new_set->vars);
1414 if (!dataflow_set_different_value)
1416 /* We have compared the variables which are in both hash tables
1417 so now only check whether there are some variables in NEW_SET->VARS
1418 which are not in OLD_SET->VARS. */
1419 htab_traverse (new_set->vars, dataflow_set_different_2, old_set->vars);
1421 return dataflow_set_different_value;
1424 /* Free the contents of dataflow set SET. */
1427 dataflow_set_destroy (dataflow_set *set)
1431 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
1432 attrs_list_clear (&set->regs[i]);
1434 htab_delete (set->vars);
1438 /* Return true if RTL X contains a SYMBOL_REF. */
1441 contains_symbol_ref (rtx x)
1450 code = GET_CODE (x);
1451 if (code == SYMBOL_REF)
1454 fmt = GET_RTX_FORMAT (code);
1455 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
1459 if (contains_symbol_ref (XEXP (x, i)))
1462 else if (fmt[i] == 'E')
1465 for (j = 0; j < XVECLEN (x, i); j++)
1466 if (contains_symbol_ref (XVECEXP (x, i, j)))
1474 /* Shall EXPR be tracked? */
1477 track_expr_p (tree expr)
1482 /* If EXPR is not a parameter or a variable do not track it. */
1483 if (TREE_CODE (expr) != VAR_DECL && TREE_CODE (expr) != PARM_DECL)
1486 /* It also must have a name... */
1487 if (!DECL_NAME (expr))
1490 /* ... and a RTL assigned to it. */
1491 decl_rtl = DECL_RTL_IF_SET (expr);
1495 /* If this expression is really a debug alias of some other declaration, we
1496 don't need to track this expression if the ultimate declaration is
1499 if (DECL_DEBUG_EXPR_IS_FROM (realdecl) && DECL_DEBUG_EXPR (realdecl))
1501 realdecl = DECL_DEBUG_EXPR (realdecl);
1502 /* ??? We don't yet know how to emit DW_OP_piece for variable
1503 that has been SRA'ed. */
1504 if (!DECL_P (realdecl))
1508 /* Do not track EXPR if REALDECL it should be ignored for debugging
1510 if (DECL_IGNORED_P (realdecl))
1513 /* Do not track global variables until we are able to emit correct location
1515 if (TREE_STATIC (realdecl))
1518 /* When the EXPR is a DECL for alias of some variable (see example)
1519 the TREE_STATIC flag is not used. Disable tracking all DECLs whose
1520 DECL_RTL contains SYMBOL_REF.
1523 extern char **_dl_argv_internal __attribute__ ((alias ("_dl_argv")));
1526 if (MEM_P (decl_rtl)
1527 && contains_symbol_ref (XEXP (decl_rtl, 0)))
1530 /* If RTX is a memory it should not be very large (because it would be
1531 an array or struct). */
1532 if (MEM_P (decl_rtl))
1534 /* Do not track structures and arrays. */
1535 if (GET_MODE (decl_rtl) == BLKmode
1536 || AGGREGATE_TYPE_P (TREE_TYPE (realdecl)))
1538 if (MEM_SIZE (decl_rtl)
1539 && INTVAL (MEM_SIZE (decl_rtl)) > MAX_VAR_PARTS)
1546 /* Return true if OFFSET is a valid offset for a register or memory
1547 access we want to track. This is used to reject out-of-bounds
1548 accesses that can cause assertions to fail later. Note that we
1549 don't reject negative offsets because they can be generated for
1550 paradoxical subregs on big-endian architectures. */
1553 offset_valid_for_tracked_p (HOST_WIDE_INT offset)
1555 return (-MAX_VAR_PARTS < offset) && (offset < MAX_VAR_PARTS);
1558 /* Determine whether a given LOC refers to the same variable part as
1562 same_variable_part_p (rtx loc, tree expr, HOST_WIDE_INT offset)
1565 HOST_WIDE_INT offset2;
1567 if (! DECL_P (expr))
1572 expr2 = REG_EXPR (loc);
1573 offset2 = REG_OFFSET (loc);
1575 else if (MEM_P (loc))
1577 expr2 = MEM_EXPR (loc);
1578 offset2 = INT_MEM_OFFSET (loc);
1583 if (! expr2 || ! DECL_P (expr2))
1586 expr = var_debug_decl (expr);
1587 expr2 = var_debug_decl (expr2);
1589 return (expr == expr2 && offset == offset2);
1593 /* Count uses (register and memory references) LOC which will be tracked.
1594 INSN is instruction which the LOC is part of. */
1597 count_uses (rtx *loc, void *insn)
1599 basic_block bb = BLOCK_FOR_INSN ((rtx) insn);
1603 gcc_assert (REGNO (*loc) < FIRST_PSEUDO_REGISTER);
1606 else if (MEM_P (*loc)
1608 && track_expr_p (MEM_EXPR (*loc))
1609 && offset_valid_for_tracked_p (INT_MEM_OFFSET (*loc)))
1617 /* Helper function for finding all uses of REG/MEM in X in insn INSN. */
1620 count_uses_1 (rtx *x, void *insn)
1622 for_each_rtx (x, count_uses, insn);
1625 /* Count stores (register and memory references) LOC which will be tracked.
1626 INSN is instruction which the LOC is part of. */
1629 count_stores (rtx loc, rtx expr ATTRIBUTE_UNUSED, void *insn)
1631 count_uses (&loc, insn);
1634 /* Add uses (register and memory references) LOC which will be tracked
1635 to VTI (bb)->mos. INSN is instruction which the LOC is part of. */
1638 add_uses (rtx *loc, void *insn)
1642 basic_block bb = BLOCK_FOR_INSN ((rtx) insn);
1643 micro_operation *mo = VTI (bb)->mos + VTI (bb)->n_mos++;
1646 && track_expr_p (REG_EXPR (*loc))
1647 && offset_valid_for_tracked_p (REG_OFFSET (*loc)))
1650 mo->type = MO_USE_NO_VAR;
1652 mo->insn = (rtx) insn;
1654 else if (MEM_P (*loc)
1656 && track_expr_p (MEM_EXPR (*loc))
1657 && offset_valid_for_tracked_p (INT_MEM_OFFSET (*loc)))
1659 basic_block bb = BLOCK_FOR_INSN ((rtx) insn);
1660 micro_operation *mo = VTI (bb)->mos + VTI (bb)->n_mos++;
1664 mo->insn = (rtx) insn;
1670 /* Helper function for finding all uses of REG/MEM in X in insn INSN. */
1673 add_uses_1 (rtx *x, void *insn)
1675 for_each_rtx (x, add_uses, insn);
1678 /* Add stores (register and memory references) LOC which will be tracked
1679 to VTI (bb)->mos. EXPR is the RTL expression containing the store.
1680 INSN is instruction which the LOC is part of. */
1683 add_stores (rtx loc, rtx expr, void *insn)
1687 basic_block bb = BLOCK_FOR_INSN ((rtx) insn);
1688 micro_operation *mo = VTI (bb)->mos + VTI (bb)->n_mos++;
1690 if (GET_CODE (expr) == CLOBBER
1692 && track_expr_p (REG_EXPR (loc))
1693 && offset_valid_for_tracked_p (REG_OFFSET (loc))))
1694 mo->type = MO_CLOBBER;
1695 else if (GET_CODE (expr) == SET
1696 && SET_DEST (expr) == loc
1697 && same_variable_part_p (SET_SRC (expr),
1704 mo->insn = NEXT_INSN ((rtx) insn);
1706 else if (MEM_P (loc)
1708 && track_expr_p (MEM_EXPR (loc))
1709 && offset_valid_for_tracked_p (INT_MEM_OFFSET (loc)))
1711 basic_block bb = BLOCK_FOR_INSN ((rtx) insn);
1712 micro_operation *mo = VTI (bb)->mos + VTI (bb)->n_mos++;
1714 if (GET_CODE (expr) == CLOBBER)
1715 mo->type = MO_CLOBBER;
1716 else if (GET_CODE (expr) == SET
1717 && SET_DEST (expr) == loc
1718 && same_variable_part_p (SET_SRC (expr),
1720 INT_MEM_OFFSET (loc)))
1725 mo->insn = NEXT_INSN ((rtx) insn);
1729 /* Compute the changes of variable locations in the basic block BB. */
1732 compute_bb_dataflow (basic_block bb)
1736 dataflow_set old_out;
1737 dataflow_set *in = &VTI (bb)->in;
1738 dataflow_set *out = &VTI (bb)->out;
1740 dataflow_set_init (&old_out, htab_elements (VTI (bb)->out.vars) + 3);
1741 dataflow_set_copy (&old_out, out);
1742 dataflow_set_copy (out, in);
1744 n = VTI (bb)->n_mos;
1745 for (i = 0; i < n; i++)
1747 switch (VTI (bb)->mos[i].type)
1750 for (r = 0; r < FIRST_PSEUDO_REGISTER; r++)
1751 if (TEST_HARD_REG_BIT (call_used_reg_set, r))
1752 var_regno_delete (out, r);
1757 rtx loc = VTI (bb)->mos[i].u.loc;
1759 if (GET_CODE (loc) == REG)
1760 var_reg_set (out, loc);
1761 else if (GET_CODE (loc) == MEM)
1762 var_mem_set (out, loc);
1768 rtx loc = VTI (bb)->mos[i].u.loc;
1771 var_reg_delete_and_set (out, loc, true);
1772 else if (MEM_P (loc))
1773 var_mem_delete_and_set (out, loc, true);
1779 rtx loc = VTI (bb)->mos[i].u.loc;
1782 var_reg_delete_and_set (out, loc, false);
1783 else if (MEM_P (loc))
1784 var_mem_delete_and_set (out, loc, false);
1790 rtx loc = VTI (bb)->mos[i].u.loc;
1793 var_reg_delete (out, loc, false);
1794 else if (MEM_P (loc))
1795 var_mem_delete (out, loc, false);
1801 rtx loc = VTI (bb)->mos[i].u.loc;
1804 var_reg_delete (out, loc, true);
1805 else if (MEM_P (loc))
1806 var_mem_delete (out, loc, true);
1811 out->stack_adjust += VTI (bb)->mos[i].u.adjust;
1816 changed = dataflow_set_different (&old_out, out);
1817 dataflow_set_destroy (&old_out);
1821 /* Find the locations of variables in the whole function. */
1824 vt_find_locations (void)
1826 fibheap_t worklist, pending, fibheap_swap;
1827 sbitmap visited, in_worklist, in_pending, sbitmap_swap;
1834 /* Compute reverse completion order of depth first search of the CFG
1835 so that the data-flow runs faster. */
1836 rc_order = XNEWVEC (int, n_basic_blocks - NUM_FIXED_BLOCKS);
1837 bb_order = XNEWVEC (int, last_basic_block);
1838 pre_and_rev_post_order_compute (NULL, rc_order, false);
1839 for (i = 0; i < n_basic_blocks - NUM_FIXED_BLOCKS; i++)
1840 bb_order[rc_order[i]] = i;
1843 worklist = fibheap_new ();
1844 pending = fibheap_new ();
1845 visited = sbitmap_alloc (last_basic_block);
1846 in_worklist = sbitmap_alloc (last_basic_block);
1847 in_pending = sbitmap_alloc (last_basic_block);
1848 sbitmap_zero (in_worklist);
1851 fibheap_insert (pending, bb_order[bb->index], bb);
1852 sbitmap_ones (in_pending);
1854 while (!fibheap_empty (pending))
1856 fibheap_swap = pending;
1858 worklist = fibheap_swap;
1859 sbitmap_swap = in_pending;
1860 in_pending = in_worklist;
1861 in_worklist = sbitmap_swap;
1863 sbitmap_zero (visited);
1865 while (!fibheap_empty (worklist))
1867 bb = fibheap_extract_min (worklist);
1868 RESET_BIT (in_worklist, bb->index);
1869 if (!TEST_BIT (visited, bb->index))
1874 SET_BIT (visited, bb->index);
1876 /* Calculate the IN set as union of predecessor OUT sets. */
1877 dataflow_set_clear (&VTI (bb)->in);
1878 FOR_EACH_EDGE (e, ei, bb->preds)
1880 dataflow_set_union (&VTI (bb)->in, &VTI (e->src)->out);
1883 changed = compute_bb_dataflow (bb);
1886 FOR_EACH_EDGE (e, ei, bb->succs)
1888 if (e->dest == EXIT_BLOCK_PTR)
1894 if (TEST_BIT (visited, e->dest->index))
1896 if (!TEST_BIT (in_pending, e->dest->index))
1898 /* Send E->DEST to next round. */
1899 SET_BIT (in_pending, e->dest->index);
1900 fibheap_insert (pending,
1901 bb_order[e->dest->index],
1905 else if (!TEST_BIT (in_worklist, e->dest->index))
1907 /* Add E->DEST to current round. */
1908 SET_BIT (in_worklist, e->dest->index);
1909 fibheap_insert (worklist, bb_order[e->dest->index],
1919 fibheap_delete (worklist);
1920 fibheap_delete (pending);
1921 sbitmap_free (visited);
1922 sbitmap_free (in_worklist);
1923 sbitmap_free (in_pending);
1926 /* Print the content of the LIST to dump file. */
1929 dump_attrs_list (attrs list)
1931 for (; list; list = list->next)
1933 print_mem_expr (dump_file, list->decl);
1934 fprintf (dump_file, "+" HOST_WIDE_INT_PRINT_DEC, list->offset);
1936 fprintf (dump_file, "\n");
1939 /* Print the information about variable *SLOT to dump file. */
1942 dump_variable (void **slot, void *data ATTRIBUTE_UNUSED)
1944 variable var = *(variable *) slot;
1946 location_chain node;
1948 fprintf (dump_file, " name: %s\n",
1949 IDENTIFIER_POINTER (DECL_NAME (var->decl)));
1950 for (i = 0; i < var->n_var_parts; i++)
1952 fprintf (dump_file, " offset %ld\n",
1953 (long) var->var_part[i].offset);
1954 for (node = var->var_part[i].loc_chain; node; node = node->next)
1956 fprintf (dump_file, " ");
1957 print_rtl_single (dump_file, node->loc);
1961 /* Continue traversing the hash table. */
1965 /* Print the information about variables from hash table VARS to dump file. */
1968 dump_vars (htab_t vars)
1970 if (htab_elements (vars) > 0)
1972 fprintf (dump_file, "Variables:\n");
1973 htab_traverse (vars, dump_variable, NULL);
1977 /* Print the dataflow set SET to dump file. */
1980 dump_dataflow_set (dataflow_set *set)
1984 fprintf (dump_file, "Stack adjustment: " HOST_WIDE_INT_PRINT_DEC "\n",
1986 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
1990 fprintf (dump_file, "Reg %d:", i);
1991 dump_attrs_list (set->regs[i]);
1994 dump_vars (set->vars);
1995 fprintf (dump_file, "\n");
1998 /* Print the IN and OUT sets for each basic block to dump file. */
2001 dump_dataflow_sets (void)
2007 fprintf (dump_file, "\nBasic block %d:\n", bb->index);
2008 fprintf (dump_file, "IN:\n");
2009 dump_dataflow_set (&VTI (bb)->in);
2010 fprintf (dump_file, "OUT:\n");
2011 dump_dataflow_set (&VTI (bb)->out);
2015 /* Add variable VAR to the hash table of changed variables and
2016 if it has no locations delete it from hash table HTAB. */
2019 variable_was_changed (variable var, htab_t htab)
2021 hashval_t hash = VARIABLE_HASH_VAL (var->decl);
2027 slot = (variable *) htab_find_slot_with_hash (changed_variables,
2028 var->decl, hash, INSERT);
2030 if (htab && var->n_var_parts == 0)
2035 empty_var = pool_alloc (var_pool);
2036 empty_var->decl = var->decl;
2037 empty_var->refcount = 1;
2038 empty_var->n_var_parts = 0;
2041 old = htab_find_slot_with_hash (htab, var->decl, hash,
2044 htab_clear_slot (htab, old);
2054 if (var->n_var_parts == 0)
2056 void **slot = htab_find_slot_with_hash (htab, var->decl, hash,
2059 htab_clear_slot (htab, slot);
2064 /* Look for the index in VAR->var_part corresponding to OFFSET.
2065 Return -1 if not found. If INSERTION_POINT is non-NULL, the
2066 referenced int will be set to the index that the part has or should
2067 have, if it should be inserted. */
2070 find_variable_location_part (variable var, HOST_WIDE_INT offset,
2071 int *insertion_point)
2075 /* Find the location part. */
2077 high = var->n_var_parts;
2080 pos = (low + high) / 2;
2081 if (var->var_part[pos].offset < offset)
2088 if (insertion_point)
2089 *insertion_point = pos;
2091 if (pos < var->n_var_parts && var->var_part[pos].offset == offset)
2097 /* Set the part of variable's location in the dataflow set SET. The variable
2098 part is specified by variable's declaration DECL and offset OFFSET and the
2099 part's location by LOC. */
2102 set_variable_part (dataflow_set *set, rtx loc, tree decl, HOST_WIDE_INT offset)
2105 location_chain node, next;
2106 location_chain *nextp;
2110 slot = htab_find_slot_with_hash (set->vars, decl,
2111 VARIABLE_HASH_VAL (decl), INSERT);
2114 /* Create new variable information. */
2115 var = pool_alloc (var_pool);
2118 var->n_var_parts = 1;
2119 var->var_part[0].offset = offset;
2120 var->var_part[0].loc_chain = NULL;
2121 var->var_part[0].cur_loc = NULL;
2129 var = (variable) *slot;
2131 pos = find_variable_location_part (var, offset, &inspos);
2135 node = var->var_part[pos].loc_chain;
2138 && ((REG_P (node->loc) && REG_P (loc)
2139 && REGNO (node->loc) == REGNO (loc))
2140 || rtx_equal_p (node->loc, loc)))
2142 /* LOC is in the beginning of the chain so we have nothing
2148 /* We have to make a copy of a shared variable. */
2149 if (var->refcount > 1)
2150 var = unshare_variable (set, var);
2155 /* We have not found the location part, new one will be created. */
2157 /* We have to make a copy of the shared variable. */
2158 if (var->refcount > 1)
2159 var = unshare_variable (set, var);
2161 /* We track only variables whose size is <= MAX_VAR_PARTS bytes
2162 thus there are at most MAX_VAR_PARTS different offsets. */
2163 gcc_assert (var->n_var_parts < MAX_VAR_PARTS);
2165 /* We have to move the elements of array starting at index
2166 inspos to the next position. */
2167 for (pos = var->n_var_parts; pos > inspos; pos--)
2168 var->var_part[pos] = var->var_part[pos - 1];
2171 var->var_part[pos].offset = offset;
2172 var->var_part[pos].loc_chain = NULL;
2173 var->var_part[pos].cur_loc = NULL;
2177 /* Delete the location from the list. */
2178 nextp = &var->var_part[pos].loc_chain;
2179 for (node = var->var_part[pos].loc_chain; node; node = next)
2182 if ((REG_P (node->loc) && REG_P (loc)
2183 && REGNO (node->loc) == REGNO (loc))
2184 || rtx_equal_p (node->loc, loc))
2186 pool_free (loc_chain_pool, node);
2191 nextp = &node->next;
2194 /* Add the location to the beginning. */
2195 node = pool_alloc (loc_chain_pool);
2197 node->next = var->var_part[pos].loc_chain;
2198 var->var_part[pos].loc_chain = node;
2200 /* If no location was emitted do so. */
2201 if (var->var_part[pos].cur_loc == NULL)
2203 var->var_part[pos].cur_loc = loc;
2204 variable_was_changed (var, set->vars);
2208 /* Remove all recorded register locations for the given variable part
2209 from dataflow set SET, except for those that are identical to loc.
2210 The variable part is specified by variable's declaration DECL and
2214 clobber_variable_part (dataflow_set *set, rtx loc, tree decl,
2215 HOST_WIDE_INT offset)
2219 if (! decl || ! DECL_P (decl))
2222 slot = htab_find_slot_with_hash (set->vars, decl, VARIABLE_HASH_VAL (decl),
2226 variable var = (variable) *slot;
2227 int pos = find_variable_location_part (var, offset, NULL);
2231 location_chain node, next;
2233 /* Remove the register locations from the dataflow set. */
2234 next = var->var_part[pos].loc_chain;
2235 for (node = next; node; node = next)
2238 if (node->loc != loc)
2240 if (REG_P (node->loc))
2245 /* Remove the variable part from the register's
2246 list, but preserve any other variable parts
2247 that might be regarded as live in that same
2249 anextp = &set->regs[REGNO (node->loc)];
2250 for (anode = *anextp; anode; anode = anext)
2252 anext = anode->next;
2253 if (anode->decl == decl
2254 && anode->offset == offset)
2256 pool_free (attrs_pool, anode);
2262 delete_variable_part (set, node->loc, decl, offset);
2269 /* Delete the part of variable's location from dataflow set SET. The variable
2270 part is specified by variable's declaration DECL and offset OFFSET and the
2271 part's location by LOC. */
2274 delete_variable_part (dataflow_set *set, rtx loc, tree decl,
2275 HOST_WIDE_INT offset)
2279 slot = htab_find_slot_with_hash (set->vars, decl, VARIABLE_HASH_VAL (decl),
2283 variable var = (variable) *slot;
2284 int pos = find_variable_location_part (var, offset, NULL);
2288 location_chain node, next;
2289 location_chain *nextp;
2292 if (var->refcount > 1)
2294 /* If the variable contains the location part we have to
2295 make a copy of the variable. */
2296 for (node = var->var_part[pos].loc_chain; node;
2299 if ((REG_P (node->loc) && REG_P (loc)
2300 && REGNO (node->loc) == REGNO (loc))
2301 || rtx_equal_p (node->loc, loc))
2303 var = unshare_variable (set, var);
2309 /* Delete the location part. */
2310 nextp = &var->var_part[pos].loc_chain;
2311 for (node = *nextp; node; node = next)
2314 if ((REG_P (node->loc) && REG_P (loc)
2315 && REGNO (node->loc) == REGNO (loc))
2316 || rtx_equal_p (node->loc, loc))
2318 pool_free (loc_chain_pool, node);
2323 nextp = &node->next;
2326 /* If we have deleted the location which was last emitted
2327 we have to emit new location so add the variable to set
2328 of changed variables. */
2329 if (var->var_part[pos].cur_loc
2331 && REG_P (var->var_part[pos].cur_loc)
2332 && REGNO (loc) == REGNO (var->var_part[pos].cur_loc))
2333 || rtx_equal_p (loc, var->var_part[pos].cur_loc)))
2336 if (var->var_part[pos].loc_chain)
2337 var->var_part[pos].cur_loc = var->var_part[pos].loc_chain->loc;
2342 if (var->var_part[pos].loc_chain == NULL)
2345 while (pos < var->n_var_parts)
2347 var->var_part[pos] = var->var_part[pos + 1];
2352 variable_was_changed (var, set->vars);
2357 /* Emit the NOTE_INSN_VAR_LOCATION for variable *VARP. DATA contains
2358 additional parameters: WHERE specifies whether the note shall be emitted
2359 before of after instruction INSN. */
2362 emit_note_insn_var_location (void **varp, void *data)
2364 variable var = *(variable *) varp;
2365 rtx insn = ((emit_note_data *)data)->insn;
2366 enum emit_note_where where = ((emit_note_data *)data)->where;
2368 int i, j, n_var_parts;
2370 HOST_WIDE_INT last_limit;
2371 tree type_size_unit;
2372 HOST_WIDE_INT offsets[MAX_VAR_PARTS];
2373 rtx loc[MAX_VAR_PARTS];
2375 gcc_assert (var->decl);
2380 for (i = 0; i < var->n_var_parts; i++)
2382 enum machine_mode mode, wider_mode;
2384 if (last_limit < var->var_part[i].offset)
2389 else if (last_limit > var->var_part[i].offset)
2391 offsets[n_var_parts] = var->var_part[i].offset;
2392 loc[n_var_parts] = var->var_part[i].loc_chain->loc;
2393 mode = GET_MODE (loc[n_var_parts]);
2394 last_limit = offsets[n_var_parts] + GET_MODE_SIZE (mode);
2396 /* Attempt to merge adjacent registers or memory. */
2397 wider_mode = GET_MODE_WIDER_MODE (mode);
2398 for (j = i + 1; j < var->n_var_parts; j++)
2399 if (last_limit <= var->var_part[j].offset)
2401 if (j < var->n_var_parts
2402 && wider_mode != VOIDmode
2403 && GET_CODE (loc[n_var_parts])
2404 == GET_CODE (var->var_part[j].loc_chain->loc)
2405 && mode == GET_MODE (var->var_part[j].loc_chain->loc)
2406 && last_limit == var->var_part[j].offset)
2409 rtx loc2 = var->var_part[j].loc_chain->loc;
2411 if (REG_P (loc[n_var_parts])
2412 && hard_regno_nregs[REGNO (loc[n_var_parts])][mode] * 2
2413 == hard_regno_nregs[REGNO (loc[n_var_parts])][wider_mode]
2414 && REGNO (loc[n_var_parts])
2415 + hard_regno_nregs[REGNO (loc[n_var_parts])][mode]
2418 if (! WORDS_BIG_ENDIAN && ! BYTES_BIG_ENDIAN)
2419 new_loc = simplify_subreg (wider_mode, loc[n_var_parts],
2421 else if (WORDS_BIG_ENDIAN && BYTES_BIG_ENDIAN)
2422 new_loc = simplify_subreg (wider_mode, loc2, mode, 0);
2425 if (!REG_P (new_loc)
2426 || REGNO (new_loc) != REGNO (loc[n_var_parts]))
2429 REG_ATTRS (new_loc) = REG_ATTRS (loc[n_var_parts]);
2432 else if (MEM_P (loc[n_var_parts])
2433 && GET_CODE (XEXP (loc2, 0)) == PLUS
2434 && GET_CODE (XEXP (XEXP (loc2, 0), 0)) == REG
2435 && GET_CODE (XEXP (XEXP (loc2, 0), 1)) == CONST_INT)
2437 if ((GET_CODE (XEXP (loc[n_var_parts], 0)) == REG
2438 && rtx_equal_p (XEXP (loc[n_var_parts], 0),
2439 XEXP (XEXP (loc2, 0), 0))
2440 && INTVAL (XEXP (XEXP (loc2, 0), 1))
2441 == GET_MODE_SIZE (mode))
2442 || (GET_CODE (XEXP (loc[n_var_parts], 0)) == PLUS
2443 && GET_CODE (XEXP (XEXP (loc[n_var_parts], 0), 1))
2445 && rtx_equal_p (XEXP (XEXP (loc[n_var_parts], 0), 0),
2446 XEXP (XEXP (loc2, 0), 0))
2447 && INTVAL (XEXP (XEXP (loc[n_var_parts], 0), 1))
2448 + GET_MODE_SIZE (mode)
2449 == INTVAL (XEXP (XEXP (loc2, 0), 1))))
2450 new_loc = adjust_address_nv (loc[n_var_parts],
2456 loc[n_var_parts] = new_loc;
2458 last_limit = offsets[n_var_parts] + GET_MODE_SIZE (mode);
2464 type_size_unit = TYPE_SIZE_UNIT (TREE_TYPE (var->decl));
2465 if ((unsigned HOST_WIDE_INT) last_limit < TREE_INT_CST_LOW (type_size_unit))
2468 if (where == EMIT_NOTE_AFTER_INSN)
2469 note = emit_note_after (NOTE_INSN_VAR_LOCATION, insn);
2471 note = emit_note_before (NOTE_INSN_VAR_LOCATION, insn);
2475 NOTE_VAR_LOCATION (note) = gen_rtx_VAR_LOCATION (VOIDmode, var->decl,
2478 else if (n_var_parts == 1)
2481 = gen_rtx_EXPR_LIST (VOIDmode, loc[0], GEN_INT (offsets[0]));
2483 NOTE_VAR_LOCATION (note) = gen_rtx_VAR_LOCATION (VOIDmode, var->decl,
2486 else if (n_var_parts)
2490 for (i = 0; i < n_var_parts; i++)
2492 = gen_rtx_EXPR_LIST (VOIDmode, loc[i], GEN_INT (offsets[i]));
2494 parallel = gen_rtx_PARALLEL (VOIDmode,
2495 gen_rtvec_v (n_var_parts, loc));
2496 NOTE_VAR_LOCATION (note) = gen_rtx_VAR_LOCATION (VOIDmode, var->decl,
2500 htab_clear_slot (changed_variables, varp);
2502 /* When there are no location parts the variable has been already
2503 removed from hash table and a new empty variable was created.
2504 Free the empty variable. */
2505 if (var->n_var_parts == 0)
2507 pool_free (var_pool, var);
2510 /* Continue traversing the hash table. */
2514 /* Emit NOTE_INSN_VAR_LOCATION note for each variable from a chain
2515 CHANGED_VARIABLES and delete this chain. WHERE specifies whether the notes
2516 shall be emitted before of after instruction INSN. */
2519 emit_notes_for_changes (rtx insn, enum emit_note_where where)
2521 emit_note_data data;
2525 htab_traverse (changed_variables, emit_note_insn_var_location, &data);
2528 /* Add variable *SLOT to the chain CHANGED_VARIABLES if it differs from the
2529 same variable in hash table DATA or is not there at all. */
2532 emit_notes_for_differences_1 (void **slot, void *data)
2534 htab_t new_vars = (htab_t) data;
2535 variable old_var, new_var;
2537 old_var = *(variable *) slot;
2538 new_var = htab_find_with_hash (new_vars, old_var->decl,
2539 VARIABLE_HASH_VAL (old_var->decl));
2543 /* Variable has disappeared. */
2546 empty_var = pool_alloc (var_pool);
2547 empty_var->decl = old_var->decl;
2548 empty_var->refcount = 1;
2549 empty_var->n_var_parts = 0;
2550 variable_was_changed (empty_var, NULL);
2552 else if (variable_different_p (old_var, new_var, true))
2554 variable_was_changed (new_var, NULL);
2557 /* Continue traversing the hash table. */
2561 /* Add variable *SLOT to the chain CHANGED_VARIABLES if it is not in hash
2565 emit_notes_for_differences_2 (void **slot, void *data)
2567 htab_t old_vars = (htab_t) data;
2568 variable old_var, new_var;
2570 new_var = *(variable *) slot;
2571 old_var = htab_find_with_hash (old_vars, new_var->decl,
2572 VARIABLE_HASH_VAL (new_var->decl));
2575 /* Variable has appeared. */
2576 variable_was_changed (new_var, NULL);
2579 /* Continue traversing the hash table. */
2583 /* Emit notes before INSN for differences between dataflow sets OLD_SET and
2587 emit_notes_for_differences (rtx insn, dataflow_set *old_set,
2588 dataflow_set *new_set)
2590 htab_traverse (old_set->vars, emit_notes_for_differences_1, new_set->vars);
2591 htab_traverse (new_set->vars, emit_notes_for_differences_2, old_set->vars);
2592 emit_notes_for_changes (insn, EMIT_NOTE_BEFORE_INSN);
2595 /* Emit the notes for changes of location parts in the basic block BB. */
2598 emit_notes_in_bb (basic_block bb)
2603 dataflow_set_init (&set, htab_elements (VTI (bb)->in.vars) + 3);
2604 dataflow_set_copy (&set, &VTI (bb)->in);
2606 for (i = 0; i < VTI (bb)->n_mos; i++)
2608 rtx insn = VTI (bb)->mos[i].insn;
2610 switch (VTI (bb)->mos[i].type)
2616 for (r = 0; r < FIRST_PSEUDO_REGISTER; r++)
2617 if (TEST_HARD_REG_BIT (call_used_reg_set, r))
2619 var_regno_delete (&set, r);
2621 emit_notes_for_changes (insn, EMIT_NOTE_AFTER_INSN);
2627 rtx loc = VTI (bb)->mos[i].u.loc;
2629 if (GET_CODE (loc) == REG)
2630 var_reg_set (&set, loc);
2632 var_mem_set (&set, loc);
2634 emit_notes_for_changes (insn, EMIT_NOTE_AFTER_INSN);
2640 rtx loc = VTI (bb)->mos[i].u.loc;
2643 var_reg_delete_and_set (&set, loc, true);
2645 var_mem_delete_and_set (&set, loc, true);
2647 emit_notes_for_changes (insn, EMIT_NOTE_BEFORE_INSN);
2653 rtx loc = VTI (bb)->mos[i].u.loc;
2656 var_reg_delete_and_set (&set, loc, false);
2658 var_mem_delete_and_set (&set, loc, false);
2660 emit_notes_for_changes (insn, EMIT_NOTE_BEFORE_INSN);
2666 rtx loc = VTI (bb)->mos[i].u.loc;
2669 var_reg_delete (&set, loc, false);
2671 var_mem_delete (&set, loc, false);
2673 emit_notes_for_changes (insn, EMIT_NOTE_AFTER_INSN);
2679 rtx loc = VTI (bb)->mos[i].u.loc;
2682 var_reg_delete (&set, loc, true);
2684 var_mem_delete (&set, loc, true);
2686 emit_notes_for_changes (insn, EMIT_NOTE_BEFORE_INSN);
2691 set.stack_adjust += VTI (bb)->mos[i].u.adjust;
2695 dataflow_set_destroy (&set);
2698 /* Emit notes for the whole function. */
2701 vt_emit_notes (void)
2704 dataflow_set *last_out;
2707 gcc_assert (!htab_elements (changed_variables));
2709 /* Enable emitting notes by functions (mainly by set_variable_part and
2710 delete_variable_part). */
2713 dataflow_set_init (&empty, 7);
2718 /* Emit the notes for changes of variable locations between two
2719 subsequent basic blocks. */
2720 emit_notes_for_differences (BB_HEAD (bb), last_out, &VTI (bb)->in);
2722 /* Emit the notes for the changes in the basic block itself. */
2723 emit_notes_in_bb (bb);
2725 last_out = &VTI (bb)->out;
2727 dataflow_set_destroy (&empty);
2731 /* If there is a declaration and offset associated with register/memory RTL
2732 assign declaration to *DECLP and offset to *OFFSETP, and return true. */
2735 vt_get_decl_and_offset (rtx rtl, tree *declp, HOST_WIDE_INT *offsetp)
2739 if (REG_ATTRS (rtl))
2741 *declp = REG_EXPR (rtl);
2742 *offsetp = REG_OFFSET (rtl);
2746 else if (MEM_P (rtl))
2748 if (MEM_ATTRS (rtl))
2750 *declp = MEM_EXPR (rtl);
2751 *offsetp = INT_MEM_OFFSET (rtl);
2758 /* Insert function parameters to IN and OUT sets of ENTRY_BLOCK. */
2761 vt_add_function_parameters (void)
2765 for (parm = DECL_ARGUMENTS (current_function_decl);
2766 parm; parm = TREE_CHAIN (parm))
2768 rtx decl_rtl = DECL_RTL_IF_SET (parm);
2769 rtx incoming = DECL_INCOMING_RTL (parm);
2771 HOST_WIDE_INT offset;
2774 if (TREE_CODE (parm) != PARM_DECL)
2777 if (!DECL_NAME (parm))
2780 if (!decl_rtl || !incoming)
2783 if (GET_MODE (decl_rtl) == BLKmode || GET_MODE (incoming) == BLKmode)
2786 if (!vt_get_decl_and_offset (incoming, &decl, &offset))
2787 if (!vt_get_decl_and_offset (decl_rtl, &decl, &offset))
2793 gcc_assert (parm == decl);
2795 out = &VTI (ENTRY_BLOCK_PTR)->out;
2797 if (REG_P (incoming))
2799 gcc_assert (REGNO (incoming) < FIRST_PSEUDO_REGISTER);
2800 attrs_list_insert (&out->regs[REGNO (incoming)],
2801 parm, offset, incoming);
2802 set_variable_part (out, incoming, parm, offset);
2804 else if (MEM_P (incoming))
2805 set_variable_part (out, incoming, parm, offset);
2809 /* Allocate and initialize the data structures for variable tracking
2810 and parse the RTL to get the micro operations. */
2813 vt_initialize (void)
2817 alloc_aux_for_blocks (sizeof (struct variable_tracking_info_def));
2822 HOST_WIDE_INT pre, post = 0;
2824 /* Count the number of micro operations. */
2825 VTI (bb)->n_mos = 0;
2826 for (insn = BB_HEAD (bb); insn != NEXT_INSN (BB_END (bb));
2827 insn = NEXT_INSN (insn))
2831 if (!frame_pointer_needed)
2833 insn_stack_adjust_offset_pre_post (insn, &pre, &post);
2839 note_uses (&PATTERN (insn), count_uses_1, insn);
2840 note_stores (PATTERN (insn), count_stores, insn);
2846 /* Add the micro-operations to the array. */
2847 VTI (bb)->mos = XNEWVEC (micro_operation, VTI (bb)->n_mos);
2848 VTI (bb)->n_mos = 0;
2849 for (insn = BB_HEAD (bb); insn != NEXT_INSN (BB_END (bb));
2850 insn = NEXT_INSN (insn))
2856 if (!frame_pointer_needed)
2858 insn_stack_adjust_offset_pre_post (insn, &pre, &post);
2861 micro_operation *mo = VTI (bb)->mos + VTI (bb)->n_mos++;
2863 mo->type = MO_ADJUST;
2869 n1 = VTI (bb)->n_mos;
2870 note_uses (&PATTERN (insn), add_uses_1, insn);
2871 n2 = VTI (bb)->n_mos - 1;
2873 /* Order the MO_USEs to be before MO_USE_NO_VARs. */
2876 while (n1 < n2 && VTI (bb)->mos[n1].type == MO_USE)
2878 while (n1 < n2 && VTI (bb)->mos[n2].type == MO_USE_NO_VAR)
2884 sw = VTI (bb)->mos[n1];
2885 VTI (bb)->mos[n1] = VTI (bb)->mos[n2];
2886 VTI (bb)->mos[n2] = sw;
2892 micro_operation *mo = VTI (bb)->mos + VTI (bb)->n_mos++;
2898 n1 = VTI (bb)->n_mos;
2899 /* This will record NEXT_INSN (insn), such that we can
2900 insert notes before it without worrying about any
2901 notes that MO_USEs might emit after the insn. */
2902 note_stores (PATTERN (insn), add_stores, insn);
2903 n2 = VTI (bb)->n_mos - 1;
2905 /* Order the MO_CLOBBERs to be before MO_SETs. */
2908 while (n1 < n2 && VTI (bb)->mos[n1].type == MO_CLOBBER)
2910 while (n1 < n2 && (VTI (bb)->mos[n2].type == MO_SET
2911 || VTI (bb)->mos[n2].type == MO_COPY))
2917 sw = VTI (bb)->mos[n1];
2918 VTI (bb)->mos[n1] = VTI (bb)->mos[n2];
2919 VTI (bb)->mos[n2] = sw;
2923 if (!frame_pointer_needed && post)
2925 micro_operation *mo = VTI (bb)->mos + VTI (bb)->n_mos++;
2927 mo->type = MO_ADJUST;
2928 mo->u.adjust = post;
2935 /* Init the IN and OUT sets. */
2938 VTI (bb)->visited = false;
2939 dataflow_set_init (&VTI (bb)->in, 7);
2940 dataflow_set_init (&VTI (bb)->out, 7);
2943 attrs_pool = create_alloc_pool ("attrs_def pool",
2944 sizeof (struct attrs_def), 1024);
2945 var_pool = create_alloc_pool ("variable_def pool",
2946 sizeof (struct variable_def), 64);
2947 loc_chain_pool = create_alloc_pool ("location_chain_def pool",
2948 sizeof (struct location_chain_def),
2950 changed_variables = htab_create (10, variable_htab_hash, variable_htab_eq,
2952 vt_add_function_parameters ();
2955 /* Free the data structures needed for variable tracking. */
2964 free (VTI (bb)->mos);
2969 dataflow_set_destroy (&VTI (bb)->in);
2970 dataflow_set_destroy (&VTI (bb)->out);
2972 free_aux_for_blocks ();
2973 free_alloc_pool (attrs_pool);
2974 free_alloc_pool (var_pool);
2975 free_alloc_pool (loc_chain_pool);
2976 htab_delete (changed_variables);
2979 /* The entry point to variable tracking pass. */
2982 variable_tracking_main (void)
2984 if (n_basic_blocks > 500 && n_edges / n_basic_blocks >= 20)
2987 mark_dfs_back_edges ();
2989 if (!frame_pointer_needed)
2991 if (!vt_stack_adjustments ())
2998 vt_find_locations ();
3001 if (dump_file && (dump_flags & TDF_DETAILS))
3003 dump_dataflow_sets ();
3004 dump_flow_info (dump_file, dump_flags);
3012 gate_handle_var_tracking (void)
3014 return (flag_var_tracking);
3019 struct tree_opt_pass pass_variable_tracking =
3021 "vartrack", /* name */
3022 gate_handle_var_tracking, /* gate */
3023 variable_tracking_main, /* execute */
3026 0, /* static_pass_number */
3027 TV_VAR_TRACKING, /* tv_id */
3028 0, /* properties_required */
3029 0, /* properties_provided */
3030 0, /* properties_destroyed */
3031 0, /* todo_flags_start */
3032 TODO_dump_func, /* todo_flags_finish */