1 /* Tree based points-to analysis
2 Copyright (C) 2005-2019 Free Software Foundation, Inc.
3 Contributed by Daniel Berlin <dberlin@dberlin.org>
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify
8 under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 GCC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
23 #include "coretypes.h"
28 #include "alloc-pool.h"
29 #include "tree-pass.h"
32 #include "tree-pretty-print.h"
33 #include "diagnostic-core.h"
34 #include "fold-const.h"
35 #include "stor-layout.h"
37 #include "gimple-iterator.h"
38 #include "tree-into-ssa.h"
41 #include "gimple-walk.h"
43 #include "stringpool.h"
48 /* The idea behind this analyzer is to generate set constraints from the
49 program, then solve the resulting constraints in order to generate the
52 Set constraints are a way of modeling program analysis problems that
53 involve sets. They consist of an inclusion constraint language,
54 describing the variables (each variable is a set) and operations that
55 are involved on the variables, and a set of rules that derive facts
56 from these operations. To solve a system of set constraints, you derive
57 all possible facts under the rules, which gives you the correct sets
60 See "Efficient Field-sensitive pointer analysis for C" by "David
61 J. Pearce and Paul H. J. Kelly and Chris Hankin, at
62 http://citeseer.ist.psu.edu/pearce04efficient.html
64 Also see "Ultra-fast Aliasing Analysis using CLA: A Million Lines
65 of C Code in a Second" by ""Nevin Heintze and Olivier Tardieu" at
66 http://citeseer.ist.psu.edu/heintze01ultrafast.html
68 There are three types of real constraint expressions, DEREF,
69 ADDRESSOF, and SCALAR. Each constraint expression consists
70 of a constraint type, a variable, and an offset.
72 SCALAR is a constraint expression type used to represent x, whether
73 it appears on the LHS or the RHS of a statement.
74 DEREF is a constraint expression type used to represent *x, whether
75 it appears on the LHS or the RHS of a statement.
76 ADDRESSOF is a constraint expression used to represent &x, whether
77 it appears on the LHS or the RHS of a statement.
79 Each pointer variable in the program is assigned an integer id, and
80 each field of a structure variable is assigned an integer id as well.
82 Structure variables are linked to their list of fields through a "next
83 field" in each variable that points to the next field in offset
85 Each variable for a structure field has
87 1. "size", that tells the size in bits of that field.
88 2. "fullsize, that tells the size in bits of the entire structure.
89 3. "offset", that tells the offset in bits from the beginning of the
90 structure to this field.
102 foo.a -> id 1, size 32, offset 0, fullsize 64, next foo.b
103 foo.b -> id 2, size 32, offset 32, fullsize 64, next NULL
104 bar -> id 3, size 32, offset 0, fullsize 32, next NULL
107 In order to solve the system of set constraints, the following is
110 1. Each constraint variable x has a solution set associated with it,
113 2. Constraints are separated into direct, copy, and complex.
114 Direct constraints are ADDRESSOF constraints that require no extra
115 processing, such as P = &Q
116 Copy constraints are those of the form P = Q.
117 Complex constraints are all the constraints involving dereferences
118 and offsets (including offsetted copies).
120 3. All direct constraints of the form P = &Q are processed, such
121 that Q is added to Sol(P)
123 4. All complex constraints for a given constraint variable are stored in a
124 linked list attached to that variable's node.
126 5. A directed graph is built out of the copy constraints. Each
127 constraint variable is a node in the graph, and an edge from
128 Q to P is added for each copy constraint of the form P = Q
130 6. The graph is then walked, and solution sets are
131 propagated along the copy edges, such that an edge from Q to P
132 causes Sol(P) <- Sol(P) union Sol(Q).
134 7. As we visit each node, all complex constraints associated with
135 that node are processed by adding appropriate copy edges to the graph, or the
136 appropriate variables to the solution set.
138 8. The process of walking the graph is iterated until no solution
141 Prior to walking the graph in steps 6 and 7, We perform static
142 cycle elimination on the constraint graph, as well
143 as off-line variable substitution.
145 TODO: Adding offsets to pointer-to-structures can be handled (IE not punted
146 on and turned into anything), but isn't. You can just see what offset
147 inside the pointed-to struct it's going to access.
149 TODO: Constant bounded arrays can be handled as if they were structs of the
150 same number of elements.
152 TODO: Modeling heap and incoming pointers becomes much better if we
153 add fields to them as we discover them, which we could do.
155 TODO: We could handle unions, but to be honest, it's probably not
156 worth the pain or slowdown. */
158 /* IPA-PTA optimizations possible.
160 When the indirect function called is ANYTHING we can add disambiguation
161 based on the function signatures (or simply the parameter count which
162 is the varinfo size). We also do not need to consider functions that
163 do not have their address taken.
165 The is_global_var bit which marks escape points is overly conservative
166 in IPA mode. Split it to is_escape_point and is_global_var - only
167 externally visible globals are escape points in IPA mode.
168 There is now is_ipa_escape_point but this is only used in a few
171 The way we introduce DECL_PT_UID to avoid fixing up all points-to
172 sets in the translation unit when we copy a DECL during inlining
173 pessimizes precision. The advantage is that the DECL_PT_UID keeps
174 compile-time and memory usage overhead low - the points-to sets
175 do not grow or get unshared as they would during a fixup phase.
176 An alternative solution is to delay IPA PTA until after all
177 inlining transformations have been applied.
179 The way we propagate clobber/use information isn't optimized.
180 It should use a new complex constraint that properly filters
181 out local variables of the callee (though that would make
182 the sets invalid after inlining). OTOH we might as well
183 admit defeat to WHOPR and simply do all the clobber/use analysis
184 and propagation after PTA finished but before we threw away
185 points-to information for memory variables. WHOPR and PTA
186 do not play along well anyway - the whole constraint solving
187 would need to be done in WPA phase and it will be very interesting
188 to apply the results to local SSA names during LTRANS phase.
190 We probably should compute a per-function unit-ESCAPE solution
191 propagating it simply like the clobber / uses solutions. The
192 solution can go alongside the non-IPA espaced solution and be
193 used to query which vars escape the unit through a function.
194 This is also required to make the escaped-HEAP trick work in IPA mode.
196 We never put function decls in points-to sets so we do not
197 keep the set of called functions for indirect calls.
199 And probably more. */
201 static bool use_field_sensitive
= true;
202 static int in_ipa_mode
= 0;
204 /* Used for predecessor bitmaps. */
205 static bitmap_obstack predbitmap_obstack
;
207 /* Used for points-to sets. */
208 static bitmap_obstack pta_obstack
;
210 /* Used for oldsolution members of variables. */
211 static bitmap_obstack oldpta_obstack
;
213 /* Used for per-solver-iteration bitmaps. */
214 static bitmap_obstack iteration_obstack
;
216 static unsigned int create_variable_info_for (tree
, const char *, bool);
217 typedef struct constraint_graph
*constraint_graph_t
;
218 static void unify_nodes (constraint_graph_t
, unsigned int, unsigned int, bool);
221 typedef struct constraint
*constraint_t
;
224 #define EXECUTE_IF_IN_NONNULL_BITMAP(a, b, c, d) \
226 EXECUTE_IF_SET_IN_BITMAP (a, b, c, d)
228 static struct constraint_stats
230 unsigned int total_vars
;
231 unsigned int nonpointer_vars
;
232 unsigned int unified_vars_static
;
233 unsigned int unified_vars_dynamic
;
234 unsigned int iterations
;
235 unsigned int num_edges
;
236 unsigned int num_implicit_edges
;
237 unsigned int points_to_sets_created
;
242 /* ID of this variable */
245 /* True if this is a variable created by the constraint analysis, such as
246 heap variables and constraints we had to break up. */
247 unsigned int is_artificial_var
: 1;
249 /* True if this is a special variable whose solution set should not be
251 unsigned int is_special_var
: 1;
253 /* True for variables whose size is not known or variable. */
254 unsigned int is_unknown_size_var
: 1;
256 /* True for (sub-)fields that represent a whole variable. */
257 unsigned int is_full_var
: 1;
259 /* True if this is a heap variable. */
260 unsigned int is_heap_var
: 1;
262 /* True if this is a register variable. */
263 unsigned int is_reg_var
: 1;
265 /* True if this field may contain pointers. */
266 unsigned int may_have_pointers
: 1;
268 /* True if this field has only restrict qualified pointers. */
269 unsigned int only_restrict_pointers
: 1;
271 /* True if this represents a heap var created for a restrict qualified
273 unsigned int is_restrict_var
: 1;
275 /* True if this represents a global variable. */
276 unsigned int is_global_var
: 1;
278 /* True if this represents a module escape point for IPA analysis. */
279 unsigned int is_ipa_escape_point
: 1;
281 /* True if this represents a IPA function info. */
282 unsigned int is_fn_info
: 1;
284 /* ??? Store somewhere better. */
287 /* The ID of the variable for the next field in this structure
288 or zero for the last field in this structure. */
291 /* The ID of the variable for the first field in this structure. */
294 /* Offset of this variable, in bits, from the base variable */
295 unsigned HOST_WIDE_INT offset
;
297 /* Size of the variable, in bits. */
298 unsigned HOST_WIDE_INT size
;
300 /* Full size of the base variable, in bits. */
301 unsigned HOST_WIDE_INT fullsize
;
303 /* In IPA mode the shadow UID in case the variable needs to be duplicated in
304 the final points-to solution because it reaches its containing
305 function recursively. Zero if none is needed. */
306 unsigned int shadow_var_uid
;
308 /* Name of this variable */
311 /* Tree that this variable is associated with. */
314 /* Points-to set for this variable. */
317 /* Old points-to set for this variable. */
320 typedef struct variable_info
*varinfo_t
;
322 static varinfo_t
first_vi_for_offset (varinfo_t
, unsigned HOST_WIDE_INT
);
323 static varinfo_t
first_or_preceding_vi_for_offset (varinfo_t
,
324 unsigned HOST_WIDE_INT
);
325 static varinfo_t
lookup_vi_for_tree (tree
);
326 static inline bool type_can_have_subvars (const_tree
);
327 static void make_param_constraints (varinfo_t
);
329 /* Pool of variable info structures. */
330 static object_allocator
<variable_info
> variable_info_pool
331 ("Variable info pool");
333 /* Map varinfo to final pt_solution. */
334 static hash_map
<varinfo_t
, pt_solution
*> *final_solutions
;
335 struct obstack final_solutions_obstack
;
337 /* Table of variable info structures for constraint variables.
338 Indexed directly by variable info id. */
339 static vec
<varinfo_t
> varmap
;
341 /* Return the varmap element N */
343 static inline varinfo_t
344 get_varinfo (unsigned int n
)
349 /* Return the next variable in the list of sub-variables of VI
350 or NULL if VI is the last sub-variable. */
352 static inline varinfo_t
353 vi_next (varinfo_t vi
)
355 return get_varinfo (vi
->next
);
358 /* Static IDs for the special variables. Variable ID zero is unused
359 and used as terminator for the sub-variable chain. */
360 enum { nothing_id
= 1, anything_id
= 2, string_id
= 3,
361 escaped_id
= 4, nonlocal_id
= 5,
362 storedanything_id
= 6, integer_id
= 7 };
364 /* Return a new variable info structure consisting for a variable
365 named NAME, and using constraint graph node NODE. Append it
366 to the vector of variable info structures. */
369 new_var_info (tree t
, const char *name
, bool add_id
)
371 unsigned index
= varmap
.length ();
372 varinfo_t ret
= variable_info_pool
.allocate ();
374 if (dump_file
&& add_id
)
376 char *tempname
= xasprintf ("%s(%d)", name
, index
);
377 name
= ggc_strdup (tempname
);
384 /* Vars without decl are artificial and do not have sub-variables. */
385 ret
->is_artificial_var
= (t
== NULL_TREE
);
386 ret
->is_special_var
= false;
387 ret
->is_unknown_size_var
= false;
388 ret
->is_full_var
= (t
== NULL_TREE
);
389 ret
->is_heap_var
= false;
390 ret
->may_have_pointers
= true;
391 ret
->only_restrict_pointers
= false;
392 ret
->is_restrict_var
= false;
394 ret
->is_global_var
= (t
== NULL_TREE
);
395 ret
->is_ipa_escape_point
= false;
396 ret
->is_fn_info
= false;
398 ret
->is_global_var
= (is_global_var (t
)
399 /* We have to treat even local register variables
401 || (VAR_P (t
) && DECL_HARD_REGISTER (t
)));
402 ret
->is_reg_var
= (t
&& TREE_CODE (t
) == SSA_NAME
);
403 ret
->solution
= BITMAP_ALLOC (&pta_obstack
);
404 ret
->oldsolution
= NULL
;
406 ret
->shadow_var_uid
= 0;
411 varmap
.safe_push (ret
);
416 /* A map mapping call statements to per-stmt variables for uses
417 and clobbers specific to the call. */
418 static hash_map
<gimple
*, varinfo_t
> *call_stmt_vars
;
420 /* Lookup or create the variable for the call statement CALL. */
423 get_call_vi (gcall
*call
)
428 varinfo_t
*slot_p
= &call_stmt_vars
->get_or_insert (call
, &existed
);
432 vi
= new_var_info (NULL_TREE
, "CALLUSED", true);
436 vi
->is_full_var
= true;
437 vi
->is_reg_var
= true;
439 vi2
= new_var_info (NULL_TREE
, "CALLCLOBBERED", true);
443 vi2
->is_full_var
= true;
444 vi2
->is_reg_var
= true;
452 /* Lookup the variable for the call statement CALL representing
453 the uses. Returns NULL if there is nothing special about this call. */
456 lookup_call_use_vi (gcall
*call
)
458 varinfo_t
*slot_p
= call_stmt_vars
->get (call
);
465 /* Lookup the variable for the call statement CALL representing
466 the clobbers. Returns NULL if there is nothing special about this call. */
469 lookup_call_clobber_vi (gcall
*call
)
471 varinfo_t uses
= lookup_call_use_vi (call
);
475 return vi_next (uses
);
478 /* Lookup or create the variable for the call statement CALL representing
482 get_call_use_vi (gcall
*call
)
484 return get_call_vi (call
);
487 /* Lookup or create the variable for the call statement CALL representing
490 static varinfo_t ATTRIBUTE_UNUSED
491 get_call_clobber_vi (gcall
*call
)
493 return vi_next (get_call_vi (call
));
497 enum constraint_expr_type
{SCALAR
, DEREF
, ADDRESSOF
};
499 /* An expression that appears in a constraint. */
501 struct constraint_expr
503 /* Constraint type. */
504 constraint_expr_type type
;
506 /* Variable we are referring to in the constraint. */
509 /* Offset, in bits, of this constraint from the beginning of
510 variables it ends up referring to.
512 IOW, in a deref constraint, we would deref, get the result set,
513 then add OFFSET to each member. */
514 HOST_WIDE_INT offset
;
517 /* Use 0x8000... as special unknown offset. */
518 #define UNKNOWN_OFFSET HOST_WIDE_INT_MIN
520 typedef struct constraint_expr ce_s
;
521 static void get_constraint_for_1 (tree
, vec
<ce_s
> *, bool, bool);
522 static void get_constraint_for (tree
, vec
<ce_s
> *);
523 static void get_constraint_for_rhs (tree
, vec
<ce_s
> *);
524 static void do_deref (vec
<ce_s
> *);
526 /* Our set constraints are made up of two constraint expressions, one
529 As described in the introduction, our set constraints each represent an
530 operation between set valued variables.
534 struct constraint_expr lhs
;
535 struct constraint_expr rhs
;
538 /* List of constraints that we use to build the constraint graph from. */
540 static vec
<constraint_t
> constraints
;
541 static object_allocator
<constraint
> constraint_pool ("Constraint pool");
543 /* The constraint graph is represented as an array of bitmaps
544 containing successor nodes. */
546 struct constraint_graph
548 /* Size of this graph, which may be different than the number of
549 nodes in the variable map. */
552 /* Explicit successors of each node. */
555 /* Implicit predecessors of each node (Used for variable
557 bitmap
*implicit_preds
;
559 /* Explicit predecessors of each node (Used for variable substitution). */
562 /* Indirect cycle representatives, or -1 if the node has no indirect
564 int *indirect_cycles
;
566 /* Representative node for a node. rep[a] == a unless the node has
570 /* Equivalence class representative for a label. This is used for
571 variable substitution. */
574 /* Pointer equivalence label for a node. All nodes with the same
575 pointer equivalence label can be unified together at some point
576 (either during constraint optimization or after the constraint
580 /* Pointer equivalence representative for a label. This is used to
581 handle nodes that are pointer equivalent but not location
582 equivalent. We can unite these once the addressof constraints
583 are transformed into initial points-to sets. */
586 /* Pointer equivalence label for each node, used during variable
588 unsigned int *pointer_label
;
590 /* Location equivalence label for each node, used during location
591 equivalence finding. */
592 unsigned int *loc_label
;
594 /* Pointed-by set for each node, used during location equivalence
595 finding. This is pointed-by rather than pointed-to, because it
596 is constructed using the predecessor graph. */
599 /* Points to sets for pointer equivalence. This is *not* the actual
600 points-to sets for nodes. */
603 /* Bitmap of nodes where the bit is set if the node is a direct
604 node. Used for variable substitution. */
605 sbitmap direct_nodes
;
607 /* Bitmap of nodes where the bit is set if the node is address
608 taken. Used for variable substitution. */
609 bitmap address_taken
;
611 /* Vector of complex constraints for each graph node. Complex
612 constraints are those involving dereferences or offsets that are
614 vec
<constraint_t
> *complex;
617 static constraint_graph_t graph
;
619 /* During variable substitution and the offline version of indirect
620 cycle finding, we create nodes to represent dereferences and
621 address taken constraints. These represent where these start and
623 #define FIRST_REF_NODE (varmap).length ()
624 #define LAST_REF_NODE (FIRST_REF_NODE + (FIRST_REF_NODE - 1))
626 /* Return the representative node for NODE, if NODE has been unioned
628 This function performs path compression along the way to finding
629 the representative. */
632 find (unsigned int node
)
634 gcc_checking_assert (node
< graph
->size
);
635 if (graph
->rep
[node
] != node
)
636 return graph
->rep
[node
] = find (graph
->rep
[node
]);
640 /* Union the TO and FROM nodes to the TO nodes.
641 Note that at some point in the future, we may want to do
642 union-by-rank, in which case we are going to have to return the
643 node we unified to. */
646 unite (unsigned int to
, unsigned int from
)
648 gcc_checking_assert (to
< graph
->size
&& from
< graph
->size
);
649 if (to
!= from
&& graph
->rep
[from
] != to
)
651 graph
->rep
[from
] = to
;
657 /* Create a new constraint consisting of LHS and RHS expressions. */
660 new_constraint (const struct constraint_expr lhs
,
661 const struct constraint_expr rhs
)
663 constraint_t ret
= constraint_pool
.allocate ();
669 /* Print out constraint C to FILE. */
672 dump_constraint (FILE *file
, constraint_t c
)
674 if (c
->lhs
.type
== ADDRESSOF
)
676 else if (c
->lhs
.type
== DEREF
)
678 fprintf (file
, "%s", get_varinfo (c
->lhs
.var
)->name
);
679 if (c
->lhs
.offset
== UNKNOWN_OFFSET
)
680 fprintf (file
, " + UNKNOWN");
681 else if (c
->lhs
.offset
!= 0)
682 fprintf (file
, " + " HOST_WIDE_INT_PRINT_DEC
, c
->lhs
.offset
);
683 fprintf (file
, " = ");
684 if (c
->rhs
.type
== ADDRESSOF
)
686 else if (c
->rhs
.type
== DEREF
)
688 fprintf (file
, "%s", get_varinfo (c
->rhs
.var
)->name
);
689 if (c
->rhs
.offset
== UNKNOWN_OFFSET
)
690 fprintf (file
, " + UNKNOWN");
691 else if (c
->rhs
.offset
!= 0)
692 fprintf (file
, " + " HOST_WIDE_INT_PRINT_DEC
, c
->rhs
.offset
);
696 void debug_constraint (constraint_t
);
697 void debug_constraints (void);
698 void debug_constraint_graph (void);
699 void debug_solution_for_var (unsigned int);
700 void debug_sa_points_to_info (void);
701 void debug_varinfo (varinfo_t
);
702 void debug_varmap (void);
704 /* Print out constraint C to stderr. */
707 debug_constraint (constraint_t c
)
709 dump_constraint (stderr
, c
);
710 fprintf (stderr
, "\n");
713 /* Print out all constraints to FILE */
716 dump_constraints (FILE *file
, int from
)
720 for (i
= from
; constraints
.iterate (i
, &c
); i
++)
723 dump_constraint (file
, c
);
724 fprintf (file
, "\n");
728 /* Print out all constraints to stderr. */
731 debug_constraints (void)
733 dump_constraints (stderr
, 0);
736 /* Print the constraint graph in dot format. */
739 dump_constraint_graph (FILE *file
)
743 /* Only print the graph if it has already been initialized: */
747 /* Prints the header of the dot file: */
748 fprintf (file
, "strict digraph {\n");
749 fprintf (file
, " node [\n shape = box\n ]\n");
750 fprintf (file
, " edge [\n fontsize = \"12\"\n ]\n");
751 fprintf (file
, "\n // List of nodes and complex constraints in "
752 "the constraint graph:\n");
754 /* The next lines print the nodes in the graph together with the
755 complex constraints attached to them. */
756 for (i
= 1; i
< graph
->size
; i
++)
758 if (i
== FIRST_REF_NODE
)
762 if (i
< FIRST_REF_NODE
)
763 fprintf (file
, "\"%s\"", get_varinfo (i
)->name
);
765 fprintf (file
, "\"*%s\"", get_varinfo (i
- FIRST_REF_NODE
)->name
);
766 if (graph
->complex[i
].exists ())
770 fprintf (file
, " [label=\"\\N\\n");
771 for (j
= 0; graph
->complex[i
].iterate (j
, &c
); ++j
)
773 dump_constraint (file
, c
);
774 fprintf (file
, "\\l");
776 fprintf (file
, "\"]");
778 fprintf (file
, ";\n");
781 /* Go over the edges. */
782 fprintf (file
, "\n // Edges in the constraint graph:\n");
783 for (i
= 1; i
< graph
->size
; i
++)
789 EXECUTE_IF_IN_NONNULL_BITMAP (graph
->succs
[i
], 0, j
, bi
)
791 unsigned to
= find (j
);
794 if (i
< FIRST_REF_NODE
)
795 fprintf (file
, "\"%s\"", get_varinfo (i
)->name
);
797 fprintf (file
, "\"*%s\"", get_varinfo (i
- FIRST_REF_NODE
)->name
);
798 fprintf (file
, " -> ");
799 if (to
< FIRST_REF_NODE
)
800 fprintf (file
, "\"%s\"", get_varinfo (to
)->name
);
802 fprintf (file
, "\"*%s\"", get_varinfo (to
- FIRST_REF_NODE
)->name
);
803 fprintf (file
, ";\n");
807 /* Prints the tail of the dot file. */
808 fprintf (file
, "}\n");
811 /* Print out the constraint graph to stderr. */
814 debug_constraint_graph (void)
816 dump_constraint_graph (stderr
);
821 The solver is a simple worklist solver, that works on the following
824 sbitmap changed_nodes = all zeroes;
826 For each node that is not already collapsed:
828 set bit in changed nodes
830 while (changed_count > 0)
832 compute topological ordering for constraint graph
834 find and collapse cycles in the constraint graph (updating
835 changed if necessary)
837 for each node (n) in the graph in topological order:
840 Process each complex constraint associated with the node,
841 updating changed if necessary.
843 For each outgoing edge from n, propagate the solution from n to
844 the destination of the edge, updating changed as necessary.
848 /* Return true if two constraint expressions A and B are equal. */
851 constraint_expr_equal (struct constraint_expr a
, struct constraint_expr b
)
853 return a
.type
== b
.type
&& a
.var
== b
.var
&& a
.offset
== b
.offset
;
856 /* Return true if constraint expression A is less than constraint expression
857 B. This is just arbitrary, but consistent, in order to give them an
861 constraint_expr_less (struct constraint_expr a
, struct constraint_expr b
)
863 if (a
.type
== b
.type
)
866 return a
.offset
< b
.offset
;
868 return a
.var
< b
.var
;
871 return a
.type
< b
.type
;
874 /* Return true if constraint A is less than constraint B. This is just
875 arbitrary, but consistent, in order to give them an ordering. */
878 constraint_less (const constraint_t
&a
, const constraint_t
&b
)
880 if (constraint_expr_less (a
->lhs
, b
->lhs
))
882 else if (constraint_expr_less (b
->lhs
, a
->lhs
))
885 return constraint_expr_less (a
->rhs
, b
->rhs
);
888 /* Return true if two constraints A and B are equal. */
891 constraint_equal (struct constraint a
, struct constraint b
)
893 return constraint_expr_equal (a
.lhs
, b
.lhs
)
894 && constraint_expr_equal (a
.rhs
, b
.rhs
);
898 /* Find a constraint LOOKFOR in the sorted constraint vector VEC */
901 constraint_vec_find (vec
<constraint_t
> vec
,
902 struct constraint lookfor
)
910 place
= vec
.lower_bound (&lookfor
, constraint_less
);
911 if (place
>= vec
.length ())
914 if (!constraint_equal (*found
, lookfor
))
919 /* Union two constraint vectors, TO and FROM. Put the result in TO.
920 Returns true of TO set is changed. */
923 constraint_set_union (vec
<constraint_t
> *to
,
924 vec
<constraint_t
> *from
)
928 bool any_change
= false;
930 FOR_EACH_VEC_ELT (*from
, i
, c
)
932 if (constraint_vec_find (*to
, *c
) == NULL
)
934 unsigned int place
= to
->lower_bound (c
, constraint_less
);
935 to
->safe_insert (place
, c
);
942 /* Expands the solution in SET to all sub-fields of variables included. */
945 solution_set_expand (bitmap set
, bitmap
*expanded
)
953 *expanded
= BITMAP_ALLOC (&iteration_obstack
);
955 /* In a first pass expand to the head of the variables we need to
956 add all sub-fields off. This avoids quadratic behavior. */
957 EXECUTE_IF_SET_IN_BITMAP (set
, 0, j
, bi
)
959 varinfo_t v
= get_varinfo (j
);
960 if (v
->is_artificial_var
963 bitmap_set_bit (*expanded
, v
->head
);
966 /* In the second pass now expand all head variables with subfields. */
967 EXECUTE_IF_SET_IN_BITMAP (*expanded
, 0, j
, bi
)
969 varinfo_t v
= get_varinfo (j
);
972 for (v
= vi_next (v
); v
!= NULL
; v
= vi_next (v
))
973 bitmap_set_bit (*expanded
, v
->id
);
976 /* And finally set the rest of the bits from SET. */
977 bitmap_ior_into (*expanded
, set
);
982 /* Union solution sets TO and DELTA, and add INC to each member of DELTA in the
986 set_union_with_increment (bitmap to
, bitmap delta
, HOST_WIDE_INT inc
,
987 bitmap
*expanded_delta
)
989 bool changed
= false;
993 /* If the solution of DELTA contains anything it is good enough to transfer
995 if (bitmap_bit_p (delta
, anything_id
))
996 return bitmap_set_bit (to
, anything_id
);
998 /* If the offset is unknown we have to expand the solution to
1000 if (inc
== UNKNOWN_OFFSET
)
1002 delta
= solution_set_expand (delta
, expanded_delta
);
1003 changed
|= bitmap_ior_into (to
, delta
);
1007 /* For non-zero offset union the offsetted solution into the destination. */
1008 EXECUTE_IF_SET_IN_BITMAP (delta
, 0, i
, bi
)
1010 varinfo_t vi
= get_varinfo (i
);
1012 /* If this is a variable with just one field just set its bit
1014 if (vi
->is_artificial_var
1015 || vi
->is_unknown_size_var
1017 changed
|= bitmap_set_bit (to
, i
);
1020 HOST_WIDE_INT fieldoffset
= vi
->offset
+ inc
;
1021 unsigned HOST_WIDE_INT size
= vi
->size
;
1023 /* If the offset makes the pointer point to before the
1024 variable use offset zero for the field lookup. */
1025 if (fieldoffset
< 0)
1026 vi
= get_varinfo (vi
->head
);
1028 vi
= first_or_preceding_vi_for_offset (vi
, fieldoffset
);
1032 changed
|= bitmap_set_bit (to
, vi
->id
);
1037 /* We have to include all fields that overlap the current field
1041 while (vi
->offset
< fieldoffset
+ size
);
1048 /* Insert constraint C into the list of complex constraints for graph
1052 insert_into_complex (constraint_graph_t graph
,
1053 unsigned int var
, constraint_t c
)
1055 vec
<constraint_t
> complex = graph
->complex[var
];
1056 unsigned int place
= complex.lower_bound (c
, constraint_less
);
1058 /* Only insert constraints that do not already exist. */
1059 if (place
>= complex.length ()
1060 || !constraint_equal (*c
, *complex[place
]))
1061 graph
->complex[var
].safe_insert (place
, c
);
1065 /* Condense two variable nodes into a single variable node, by moving
1066 all associated info from FROM to TO. Returns true if TO node's
1067 constraint set changes after the merge. */
1070 merge_node_constraints (constraint_graph_t graph
, unsigned int to
,
1075 bool any_change
= false;
1077 gcc_checking_assert (find (from
) == to
);
1079 /* Move all complex constraints from src node into to node */
1080 FOR_EACH_VEC_ELT (graph
->complex[from
], i
, c
)
1082 /* In complex constraints for node FROM, we may have either
1083 a = *FROM, and *FROM = a, or an offseted constraint which are
1084 always added to the rhs node's constraints. */
1086 if (c
->rhs
.type
== DEREF
)
1088 else if (c
->lhs
.type
== DEREF
)
1094 any_change
= constraint_set_union (&graph
->complex[to
],
1095 &graph
->complex[from
]);
1096 graph
->complex[from
].release ();
1101 /* Remove edges involving NODE from GRAPH. */
1104 clear_edges_for_node (constraint_graph_t graph
, unsigned int node
)
1106 if (graph
->succs
[node
])
1107 BITMAP_FREE (graph
->succs
[node
]);
1110 /* Merge GRAPH nodes FROM and TO into node TO. */
1113 merge_graph_nodes (constraint_graph_t graph
, unsigned int to
,
1116 if (graph
->indirect_cycles
[from
] != -1)
1118 /* If we have indirect cycles with the from node, and we have
1119 none on the to node, the to node has indirect cycles from the
1120 from node now that they are unified.
1121 If indirect cycles exist on both, unify the nodes that they
1122 are in a cycle with, since we know they are in a cycle with
1124 if (graph
->indirect_cycles
[to
] == -1)
1125 graph
->indirect_cycles
[to
] = graph
->indirect_cycles
[from
];
1128 /* Merge all the successor edges. */
1129 if (graph
->succs
[from
])
1131 if (!graph
->succs
[to
])
1132 graph
->succs
[to
] = BITMAP_ALLOC (&pta_obstack
);
1133 bitmap_ior_into (graph
->succs
[to
],
1134 graph
->succs
[from
]);
1137 clear_edges_for_node (graph
, from
);
1141 /* Add an indirect graph edge to GRAPH, going from TO to FROM if
1142 it doesn't exist in the graph already. */
1145 add_implicit_graph_edge (constraint_graph_t graph
, unsigned int to
,
1151 if (!graph
->implicit_preds
[to
])
1152 graph
->implicit_preds
[to
] = BITMAP_ALLOC (&predbitmap_obstack
);
1154 if (bitmap_set_bit (graph
->implicit_preds
[to
], from
))
1155 stats
.num_implicit_edges
++;
1158 /* Add a predecessor graph edge to GRAPH, going from TO to FROM if
1159 it doesn't exist in the graph already.
1160 Return false if the edge already existed, true otherwise. */
1163 add_pred_graph_edge (constraint_graph_t graph
, unsigned int to
,
1166 if (!graph
->preds
[to
])
1167 graph
->preds
[to
] = BITMAP_ALLOC (&predbitmap_obstack
);
1168 bitmap_set_bit (graph
->preds
[to
], from
);
1171 /* Add a graph edge to GRAPH, going from FROM to TO if
1172 it doesn't exist in the graph already.
1173 Return false if the edge already existed, true otherwise. */
1176 add_graph_edge (constraint_graph_t graph
, unsigned int to
,
1187 if (!graph
->succs
[from
])
1188 graph
->succs
[from
] = BITMAP_ALLOC (&pta_obstack
);
1189 if (bitmap_set_bit (graph
->succs
[from
], to
))
1192 if (to
< FIRST_REF_NODE
&& from
< FIRST_REF_NODE
)
1200 /* Initialize the constraint graph structure to contain SIZE nodes. */
1203 init_graph (unsigned int size
)
1207 graph
= XCNEW (struct constraint_graph
);
1209 graph
->succs
= XCNEWVEC (bitmap
, graph
->size
);
1210 graph
->indirect_cycles
= XNEWVEC (int, graph
->size
);
1211 graph
->rep
= XNEWVEC (unsigned int, graph
->size
);
1212 /* ??? Macros do not support template types with multiple arguments,
1213 so we use a typedef to work around it. */
1214 typedef vec
<constraint_t
> vec_constraint_t_heap
;
1215 graph
->complex = XCNEWVEC (vec_constraint_t_heap
, size
);
1216 graph
->pe
= XCNEWVEC (unsigned int, graph
->size
);
1217 graph
->pe_rep
= XNEWVEC (int, graph
->size
);
1219 for (j
= 0; j
< graph
->size
; j
++)
1222 graph
->pe_rep
[j
] = -1;
1223 graph
->indirect_cycles
[j
] = -1;
1227 /* Build the constraint graph, adding only predecessor edges right now. */
1230 build_pred_graph (void)
1236 graph
->implicit_preds
= XCNEWVEC (bitmap
, graph
->size
);
1237 graph
->preds
= XCNEWVEC (bitmap
, graph
->size
);
1238 graph
->pointer_label
= XCNEWVEC (unsigned int, graph
->size
);
1239 graph
->loc_label
= XCNEWVEC (unsigned int, graph
->size
);
1240 graph
->pointed_by
= XCNEWVEC (bitmap
, graph
->size
);
1241 graph
->points_to
= XCNEWVEC (bitmap
, graph
->size
);
1242 graph
->eq_rep
= XNEWVEC (int, graph
->size
);
1243 graph
->direct_nodes
= sbitmap_alloc (graph
->size
);
1244 graph
->address_taken
= BITMAP_ALLOC (&predbitmap_obstack
);
1245 bitmap_clear (graph
->direct_nodes
);
1247 for (j
= 1; j
< FIRST_REF_NODE
; j
++)
1249 if (!get_varinfo (j
)->is_special_var
)
1250 bitmap_set_bit (graph
->direct_nodes
, j
);
1253 for (j
= 0; j
< graph
->size
; j
++)
1254 graph
->eq_rep
[j
] = -1;
1256 for (j
= 0; j
< varmap
.length (); j
++)
1257 graph
->indirect_cycles
[j
] = -1;
1259 FOR_EACH_VEC_ELT (constraints
, i
, c
)
1261 struct constraint_expr lhs
= c
->lhs
;
1262 struct constraint_expr rhs
= c
->rhs
;
1263 unsigned int lhsvar
= lhs
.var
;
1264 unsigned int rhsvar
= rhs
.var
;
1266 if (lhs
.type
== DEREF
)
1269 if (rhs
.offset
== 0 && lhs
.offset
== 0 && rhs
.type
== SCALAR
)
1270 add_pred_graph_edge (graph
, FIRST_REF_NODE
+ lhsvar
, rhsvar
);
1272 else if (rhs
.type
== DEREF
)
1275 if (rhs
.offset
== 0 && lhs
.offset
== 0 && lhs
.type
== SCALAR
)
1276 add_pred_graph_edge (graph
, lhsvar
, FIRST_REF_NODE
+ rhsvar
);
1278 bitmap_clear_bit (graph
->direct_nodes
, lhsvar
);
1280 else if (rhs
.type
== ADDRESSOF
)
1285 if (graph
->points_to
[lhsvar
] == NULL
)
1286 graph
->points_to
[lhsvar
] = BITMAP_ALLOC (&predbitmap_obstack
);
1287 bitmap_set_bit (graph
->points_to
[lhsvar
], rhsvar
);
1289 if (graph
->pointed_by
[rhsvar
] == NULL
)
1290 graph
->pointed_by
[rhsvar
] = BITMAP_ALLOC (&predbitmap_obstack
);
1291 bitmap_set_bit (graph
->pointed_by
[rhsvar
], lhsvar
);
1293 /* Implicitly, *x = y */
1294 add_implicit_graph_edge (graph
, FIRST_REF_NODE
+ lhsvar
, rhsvar
);
1296 /* All related variables are no longer direct nodes. */
1297 bitmap_clear_bit (graph
->direct_nodes
, rhsvar
);
1298 v
= get_varinfo (rhsvar
);
1299 if (!v
->is_full_var
)
1301 v
= get_varinfo (v
->head
);
1304 bitmap_clear_bit (graph
->direct_nodes
, v
->id
);
1309 bitmap_set_bit (graph
->address_taken
, rhsvar
);
1311 else if (lhsvar
> anything_id
1312 && lhsvar
!= rhsvar
&& lhs
.offset
== 0 && rhs
.offset
== 0)
1315 add_pred_graph_edge (graph
, lhsvar
, rhsvar
);
1316 /* Implicitly, *x = *y */
1317 add_implicit_graph_edge (graph
, FIRST_REF_NODE
+ lhsvar
,
1318 FIRST_REF_NODE
+ rhsvar
);
1320 else if (lhs
.offset
!= 0 || rhs
.offset
!= 0)
1322 if (rhs
.offset
!= 0)
1323 bitmap_clear_bit (graph
->direct_nodes
, lhs
.var
);
1324 else if (lhs
.offset
!= 0)
1325 bitmap_clear_bit (graph
->direct_nodes
, rhs
.var
);
1330 /* Build the constraint graph, adding successor edges. */
1333 build_succ_graph (void)
1338 FOR_EACH_VEC_ELT (constraints
, i
, c
)
1340 struct constraint_expr lhs
;
1341 struct constraint_expr rhs
;
1342 unsigned int lhsvar
;
1343 unsigned int rhsvar
;
1350 lhsvar
= find (lhs
.var
);
1351 rhsvar
= find (rhs
.var
);
1353 if (lhs
.type
== DEREF
)
1355 if (rhs
.offset
== 0 && lhs
.offset
== 0 && rhs
.type
== SCALAR
)
1356 add_graph_edge (graph
, FIRST_REF_NODE
+ lhsvar
, rhsvar
);
1358 else if (rhs
.type
== DEREF
)
1360 if (rhs
.offset
== 0 && lhs
.offset
== 0 && lhs
.type
== SCALAR
)
1361 add_graph_edge (graph
, lhsvar
, FIRST_REF_NODE
+ rhsvar
);
1363 else if (rhs
.type
== ADDRESSOF
)
1366 gcc_checking_assert (find (rhs
.var
) == rhs
.var
);
1367 bitmap_set_bit (get_varinfo (lhsvar
)->solution
, rhsvar
);
1369 else if (lhsvar
> anything_id
1370 && lhsvar
!= rhsvar
&& lhs
.offset
== 0 && rhs
.offset
== 0)
1372 add_graph_edge (graph
, lhsvar
, rhsvar
);
1376 /* Add edges from STOREDANYTHING to all non-direct nodes that can
1377 receive pointers. */
1378 t
= find (storedanything_id
);
1379 for (i
= integer_id
+ 1; i
< FIRST_REF_NODE
; ++i
)
1381 if (!bitmap_bit_p (graph
->direct_nodes
, i
)
1382 && get_varinfo (i
)->may_have_pointers
)
1383 add_graph_edge (graph
, find (i
), t
);
1386 /* Everything stored to ANYTHING also potentially escapes. */
1387 add_graph_edge (graph
, find (escaped_id
), t
);
1391 /* Changed variables on the last iteration. */
1392 static bitmap changed
;
1394 /* Strongly Connected Component visitation info. */
1398 scc_info (size_t size
);
1401 auto_sbitmap visited
;
1402 auto_sbitmap deleted
;
1404 unsigned int *node_mapping
;
1406 auto_vec
<unsigned> scc_stack
;
1410 /* Recursive routine to find strongly connected components in GRAPH.
1411 SI is the SCC info to store the information in, and N is the id of current
1412 graph node we are processing.
1414 This is Tarjan's strongly connected component finding algorithm, as
1415 modified by Nuutila to keep only non-root nodes on the stack.
1416 The algorithm can be found in "On finding the strongly connected
1417 connected components in a directed graph" by Esko Nuutila and Eljas
1418 Soisalon-Soininen, in Information Processing Letters volume 49,
1419 number 1, pages 9-14. */
1422 scc_visit (constraint_graph_t graph
, struct scc_info
*si
, unsigned int n
)
1426 unsigned int my_dfs
;
1428 bitmap_set_bit (si
->visited
, n
);
1429 si
->dfs
[n
] = si
->current_index
++;
1430 my_dfs
= si
->dfs
[n
];
1432 /* Visit all the successors. */
1433 EXECUTE_IF_IN_NONNULL_BITMAP (graph
->succs
[n
], 0, i
, bi
)
1437 if (i
> LAST_REF_NODE
)
1441 if (bitmap_bit_p (si
->deleted
, w
))
1444 if (!bitmap_bit_p (si
->visited
, w
))
1445 scc_visit (graph
, si
, w
);
1447 unsigned int t
= find (w
);
1448 gcc_checking_assert (find (n
) == n
);
1449 if (si
->dfs
[t
] < si
->dfs
[n
])
1450 si
->dfs
[n
] = si
->dfs
[t
];
1453 /* See if any components have been identified. */
1454 if (si
->dfs
[n
] == my_dfs
)
1456 if (si
->scc_stack
.length () > 0
1457 && si
->dfs
[si
->scc_stack
.last ()] >= my_dfs
)
1459 bitmap scc
= BITMAP_ALLOC (NULL
);
1460 unsigned int lowest_node
;
1463 bitmap_set_bit (scc
, n
);
1465 while (si
->scc_stack
.length () != 0
1466 && si
->dfs
[si
->scc_stack
.last ()] >= my_dfs
)
1468 unsigned int w
= si
->scc_stack
.pop ();
1470 bitmap_set_bit (scc
, w
);
1473 lowest_node
= bitmap_first_set_bit (scc
);
1474 gcc_assert (lowest_node
< FIRST_REF_NODE
);
1476 /* Collapse the SCC nodes into a single node, and mark the
1478 EXECUTE_IF_SET_IN_BITMAP (scc
, 0, i
, bi
)
1480 if (i
< FIRST_REF_NODE
)
1482 if (unite (lowest_node
, i
))
1483 unify_nodes (graph
, lowest_node
, i
, false);
1487 unite (lowest_node
, i
);
1488 graph
->indirect_cycles
[i
- FIRST_REF_NODE
] = lowest_node
;
1492 bitmap_set_bit (si
->deleted
, n
);
1495 si
->scc_stack
.safe_push (n
);
1498 /* Unify node FROM into node TO, updating the changed count if
1499 necessary when UPDATE_CHANGED is true. */
1502 unify_nodes (constraint_graph_t graph
, unsigned int to
, unsigned int from
,
1503 bool update_changed
)
1505 gcc_checking_assert (to
!= from
&& find (to
) == to
);
1507 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
1508 fprintf (dump_file
, "Unifying %s to %s\n",
1509 get_varinfo (from
)->name
,
1510 get_varinfo (to
)->name
);
1513 stats
.unified_vars_dynamic
++;
1515 stats
.unified_vars_static
++;
1517 merge_graph_nodes (graph
, to
, from
);
1518 if (merge_node_constraints (graph
, to
, from
))
1521 bitmap_set_bit (changed
, to
);
1524 /* Mark TO as changed if FROM was changed. If TO was already marked
1525 as changed, decrease the changed count. */
1528 && bitmap_clear_bit (changed
, from
))
1529 bitmap_set_bit (changed
, to
);
1530 varinfo_t fromvi
= get_varinfo (from
);
1531 if (fromvi
->solution
)
1533 /* If the solution changes because of the merging, we need to mark
1534 the variable as changed. */
1535 varinfo_t tovi
= get_varinfo (to
);
1536 if (bitmap_ior_into (tovi
->solution
, fromvi
->solution
))
1539 bitmap_set_bit (changed
, to
);
1542 BITMAP_FREE (fromvi
->solution
);
1543 if (fromvi
->oldsolution
)
1544 BITMAP_FREE (fromvi
->oldsolution
);
1546 if (stats
.iterations
> 0
1547 && tovi
->oldsolution
)
1548 BITMAP_FREE (tovi
->oldsolution
);
1550 if (graph
->succs
[to
])
1551 bitmap_clear_bit (graph
->succs
[to
], to
);
1554 /* Information needed to compute the topological ordering of a graph. */
1558 /* sbitmap of visited nodes. */
1560 /* Array that stores the topological order of the graph, *in
1562 vec
<unsigned> topo_order
;
1566 /* Initialize and return a topological info structure. */
1568 static struct topo_info
*
1569 init_topo_info (void)
1571 size_t size
= graph
->size
;
1572 struct topo_info
*ti
= XNEW (struct topo_info
);
1573 ti
->visited
= sbitmap_alloc (size
);
1574 bitmap_clear (ti
->visited
);
1575 ti
->topo_order
.create (1);
1580 /* Free the topological sort info pointed to by TI. */
1583 free_topo_info (struct topo_info
*ti
)
1585 sbitmap_free (ti
->visited
);
1586 ti
->topo_order
.release ();
1590 /* Visit the graph in topological order, and store the order in the
1591 topo_info structure. */
1594 topo_visit (constraint_graph_t graph
, struct topo_info
*ti
,
1600 bitmap_set_bit (ti
->visited
, n
);
1602 if (graph
->succs
[n
])
1603 EXECUTE_IF_SET_IN_BITMAP (graph
->succs
[n
], 0, j
, bi
)
1605 if (!bitmap_bit_p (ti
->visited
, j
))
1606 topo_visit (graph
, ti
, j
);
1609 ti
->topo_order
.safe_push (n
);
1612 /* Process a constraint C that represents x = *(y + off), using DELTA as the
1613 starting solution for y. */
1616 do_sd_constraint (constraint_graph_t graph
, constraint_t c
,
1617 bitmap delta
, bitmap
*expanded_delta
)
1619 unsigned int lhs
= c
->lhs
.var
;
1621 bitmap sol
= get_varinfo (lhs
)->solution
;
1624 HOST_WIDE_INT roffset
= c
->rhs
.offset
;
1626 /* Our IL does not allow this. */
1627 gcc_checking_assert (c
->lhs
.offset
== 0);
1629 /* If the solution of Y contains anything it is good enough to transfer
1631 if (bitmap_bit_p (delta
, anything_id
))
1633 flag
|= bitmap_set_bit (sol
, anything_id
);
1637 /* If we do not know at with offset the rhs is dereferenced compute
1638 the reachability set of DELTA, conservatively assuming it is
1639 dereferenced at all valid offsets. */
1640 if (roffset
== UNKNOWN_OFFSET
)
1642 delta
= solution_set_expand (delta
, expanded_delta
);
1643 /* No further offset processing is necessary. */
1647 /* For each variable j in delta (Sol(y)), add
1648 an edge in the graph from j to x, and union Sol(j) into Sol(x). */
1649 EXECUTE_IF_SET_IN_BITMAP (delta
, 0, j
, bi
)
1651 varinfo_t v
= get_varinfo (j
);
1652 HOST_WIDE_INT fieldoffset
= v
->offset
+ roffset
;
1653 unsigned HOST_WIDE_INT size
= v
->size
;
1658 else if (roffset
!= 0)
1660 if (fieldoffset
< 0)
1661 v
= get_varinfo (v
->head
);
1663 v
= first_or_preceding_vi_for_offset (v
, fieldoffset
);
1666 /* We have to include all fields that overlap the current field
1667 shifted by roffset. */
1672 /* Adding edges from the special vars is pointless.
1673 They don't have sets that can change. */
1674 if (get_varinfo (t
)->is_special_var
)
1675 flag
|= bitmap_ior_into (sol
, get_varinfo (t
)->solution
);
1676 /* Merging the solution from ESCAPED needlessly increases
1677 the set. Use ESCAPED as representative instead. */
1678 else if (v
->id
== escaped_id
)
1679 flag
|= bitmap_set_bit (sol
, escaped_id
);
1680 else if (v
->may_have_pointers
1681 && add_graph_edge (graph
, lhs
, t
))
1682 flag
|= bitmap_ior_into (sol
, get_varinfo (t
)->solution
);
1690 while (v
->offset
< fieldoffset
+ size
);
1694 /* If the LHS solution changed, mark the var as changed. */
1697 get_varinfo (lhs
)->solution
= sol
;
1698 bitmap_set_bit (changed
, lhs
);
1702 /* Process a constraint C that represents *(x + off) = y using DELTA
1703 as the starting solution for x. */
1706 do_ds_constraint (constraint_t c
, bitmap delta
, bitmap
*expanded_delta
)
1708 unsigned int rhs
= c
->rhs
.var
;
1709 bitmap sol
= get_varinfo (rhs
)->solution
;
1712 HOST_WIDE_INT loff
= c
->lhs
.offset
;
1713 bool escaped_p
= false;
1715 /* Our IL does not allow this. */
1716 gcc_checking_assert (c
->rhs
.offset
== 0);
1718 /* If the solution of y contains ANYTHING simply use the ANYTHING
1719 solution. This avoids needlessly increasing the points-to sets. */
1720 if (bitmap_bit_p (sol
, anything_id
))
1721 sol
= get_varinfo (find (anything_id
))->solution
;
1723 /* If the solution for x contains ANYTHING we have to merge the
1724 solution of y into all pointer variables which we do via
1726 if (bitmap_bit_p (delta
, anything_id
))
1728 unsigned t
= find (storedanything_id
);
1729 if (add_graph_edge (graph
, t
, rhs
))
1731 if (bitmap_ior_into (get_varinfo (t
)->solution
, sol
))
1732 bitmap_set_bit (changed
, t
);
1737 /* If we do not know at with offset the rhs is dereferenced compute
1738 the reachability set of DELTA, conservatively assuming it is
1739 dereferenced at all valid offsets. */
1740 if (loff
== UNKNOWN_OFFSET
)
1742 delta
= solution_set_expand (delta
, expanded_delta
);
1746 /* For each member j of delta (Sol(x)), add an edge from y to j and
1747 union Sol(y) into Sol(j) */
1748 EXECUTE_IF_SET_IN_BITMAP (delta
, 0, j
, bi
)
1750 varinfo_t v
= get_varinfo (j
);
1752 HOST_WIDE_INT fieldoffset
= v
->offset
+ loff
;
1753 unsigned HOST_WIDE_INT size
= v
->size
;
1759 if (fieldoffset
< 0)
1760 v
= get_varinfo (v
->head
);
1762 v
= first_or_preceding_vi_for_offset (v
, fieldoffset
);
1765 /* We have to include all fields that overlap the current field
1769 if (v
->may_have_pointers
)
1771 /* If v is a global variable then this is an escape point. */
1772 if (v
->is_global_var
1775 t
= find (escaped_id
);
1776 if (add_graph_edge (graph
, t
, rhs
)
1777 && bitmap_ior_into (get_varinfo (t
)->solution
, sol
))
1778 bitmap_set_bit (changed
, t
);
1779 /* Enough to let rhs escape once. */
1783 if (v
->is_special_var
)
1787 if (add_graph_edge (graph
, t
, rhs
)
1788 && bitmap_ior_into (get_varinfo (t
)->solution
, sol
))
1789 bitmap_set_bit (changed
, t
);
1798 while (v
->offset
< fieldoffset
+ size
);
1802 /* Handle a non-simple (simple meaning requires no iteration),
1803 constraint (IE *x = &y, x = *y, *x = y, and x = y with offsets involved). */
1806 do_complex_constraint (constraint_graph_t graph
, constraint_t c
, bitmap delta
,
1807 bitmap
*expanded_delta
)
1809 if (c
->lhs
.type
== DEREF
)
1811 if (c
->rhs
.type
== ADDRESSOF
)
1818 do_ds_constraint (c
, delta
, expanded_delta
);
1821 else if (c
->rhs
.type
== DEREF
)
1824 if (!(get_varinfo (c
->lhs
.var
)->is_special_var
))
1825 do_sd_constraint (graph
, c
, delta
, expanded_delta
);
1832 gcc_checking_assert (c
->rhs
.type
== SCALAR
&& c
->lhs
.type
== SCALAR
1833 && c
->rhs
.offset
!= 0 && c
->lhs
.offset
== 0);
1834 tmp
= get_varinfo (c
->lhs
.var
)->solution
;
1836 flag
= set_union_with_increment (tmp
, delta
, c
->rhs
.offset
,
1840 bitmap_set_bit (changed
, c
->lhs
.var
);
1844 /* Initialize and return a new SCC info structure. */
1846 scc_info::scc_info (size_t size
) :
1847 visited (size
), deleted (size
), current_index (0), scc_stack (1)
1849 bitmap_clear (visited
);
1850 bitmap_clear (deleted
);
1851 node_mapping
= XNEWVEC (unsigned int, size
);
1852 dfs
= XCNEWVEC (unsigned int, size
);
1854 for (size_t i
= 0; i
< size
; i
++)
1855 node_mapping
[i
] = i
;
1858 /* Free an SCC info structure pointed to by SI */
1860 scc_info::~scc_info ()
1862 free (node_mapping
);
1867 /* Find indirect cycles in GRAPH that occur, using strongly connected
1868 components, and note them in the indirect cycles map.
1870 This technique comes from Ben Hardekopf and Calvin Lin,
1871 "It Pays to be Lazy: Fast and Accurate Pointer Analysis for Millions of
1872 Lines of Code", submitted to PLDI 2007. */
1875 find_indirect_cycles (constraint_graph_t graph
)
1878 unsigned int size
= graph
->size
;
1881 for (i
= 0; i
< MIN (LAST_REF_NODE
, size
); i
++ )
1882 if (!bitmap_bit_p (si
.visited
, i
) && find (i
) == i
)
1883 scc_visit (graph
, &si
, i
);
1886 /* Compute a topological ordering for GRAPH, and store the result in the
1887 topo_info structure TI. */
1890 compute_topo_order (constraint_graph_t graph
,
1891 struct topo_info
*ti
)
1894 unsigned int size
= graph
->size
;
1896 for (i
= 0; i
!= size
; ++i
)
1897 if (!bitmap_bit_p (ti
->visited
, i
) && find (i
) == i
)
1898 topo_visit (graph
, ti
, i
);
1901 /* Structure used to for hash value numbering of pointer equivalence
1904 typedef struct equiv_class_label
1907 unsigned int equivalence_class
;
1909 } *equiv_class_label_t
;
1910 typedef const struct equiv_class_label
*const_equiv_class_label_t
;
1912 /* Equiv_class_label hashtable helpers. */
1914 struct equiv_class_hasher
: free_ptr_hash
<equiv_class_label
>
1916 static inline hashval_t
hash (const equiv_class_label
*);
1917 static inline bool equal (const equiv_class_label
*,
1918 const equiv_class_label
*);
1921 /* Hash function for a equiv_class_label_t */
1924 equiv_class_hasher::hash (const equiv_class_label
*ecl
)
1926 return ecl
->hashcode
;
1929 /* Equality function for two equiv_class_label_t's. */
1932 equiv_class_hasher::equal (const equiv_class_label
*eql1
,
1933 const equiv_class_label
*eql2
)
1935 return (eql1
->hashcode
== eql2
->hashcode
1936 && bitmap_equal_p (eql1
->labels
, eql2
->labels
));
1939 /* A hashtable for mapping a bitmap of labels->pointer equivalence
1941 static hash_table
<equiv_class_hasher
> *pointer_equiv_class_table
;
1943 /* A hashtable for mapping a bitmap of labels->location equivalence
1945 static hash_table
<equiv_class_hasher
> *location_equiv_class_table
;
1947 /* Lookup a equivalence class in TABLE by the bitmap of LABELS with
1948 hash HAS it contains. Sets *REF_LABELS to the bitmap LABELS
1949 is equivalent to. */
1951 static equiv_class_label
*
1952 equiv_class_lookup_or_add (hash_table
<equiv_class_hasher
> *table
,
1955 equiv_class_label
**slot
;
1956 equiv_class_label ecl
;
1958 ecl
.labels
= labels
;
1959 ecl
.hashcode
= bitmap_hash (labels
);
1960 slot
= table
->find_slot (&ecl
, INSERT
);
1963 *slot
= XNEW (struct equiv_class_label
);
1964 (*slot
)->labels
= labels
;
1965 (*slot
)->hashcode
= ecl
.hashcode
;
1966 (*slot
)->equivalence_class
= 0;
1972 /* Perform offline variable substitution.
1974 This is a worst case quadratic time way of identifying variables
1975 that must have equivalent points-to sets, including those caused by
1976 static cycles, and single entry subgraphs, in the constraint graph.
1978 The technique is described in "Exploiting Pointer and Location
1979 Equivalence to Optimize Pointer Analysis. In the 14th International
1980 Static Analysis Symposium (SAS), August 2007." It is known as the
1981 "HU" algorithm, and is equivalent to value numbering the collapsed
1982 constraint graph including evaluating unions.
1984 The general method of finding equivalence classes is as follows:
1985 Add fake nodes (REF nodes) and edges for *a = b and a = *b constraints.
1986 Initialize all non-REF nodes to be direct nodes.
1987 For each constraint a = a U {b}, we set pts(a) = pts(a) u {fresh
1989 For each constraint containing the dereference, we also do the same
1992 We then compute SCC's in the graph and unify nodes in the same SCC,
1995 For each non-collapsed node x:
1996 Visit all unvisited explicit incoming edges.
1997 Ignoring all non-pointers, set pts(x) = Union of pts(a) for y
1999 Lookup the equivalence class for pts(x).
2000 If we found one, equivalence_class(x) = found class.
2001 Otherwise, equivalence_class(x) = new class, and new_class is
2002 added to the lookup table.
2004 All direct nodes with the same equivalence class can be replaced
2005 with a single representative node.
2006 All unlabeled nodes (label == 0) are not pointers and all edges
2007 involving them can be eliminated.
2008 We perform these optimizations during rewrite_constraints
2010 In addition to pointer equivalence class finding, we also perform
2011 location equivalence class finding. This is the set of variables
2012 that always appear together in points-to sets. We use this to
2013 compress the size of the points-to sets. */
2015 /* Current maximum pointer equivalence class id. */
2016 static int pointer_equiv_class
;
2018 /* Current maximum location equivalence class id. */
2019 static int location_equiv_class
;
2021 /* Recursive routine to find strongly connected components in GRAPH,
2022 and label it's nodes with DFS numbers. */
2025 condense_visit (constraint_graph_t graph
, struct scc_info
*si
, unsigned int n
)
2029 unsigned int my_dfs
;
2031 gcc_checking_assert (si
->node_mapping
[n
] == n
);
2032 bitmap_set_bit (si
->visited
, n
);
2033 si
->dfs
[n
] = si
->current_index
++;
2034 my_dfs
= si
->dfs
[n
];
2036 /* Visit all the successors. */
2037 EXECUTE_IF_IN_NONNULL_BITMAP (graph
->preds
[n
], 0, i
, bi
)
2039 unsigned int w
= si
->node_mapping
[i
];
2041 if (bitmap_bit_p (si
->deleted
, w
))
2044 if (!bitmap_bit_p (si
->visited
, w
))
2045 condense_visit (graph
, si
, w
);
2047 unsigned int t
= si
->node_mapping
[w
];
2048 gcc_checking_assert (si
->node_mapping
[n
] == n
);
2049 if (si
->dfs
[t
] < si
->dfs
[n
])
2050 si
->dfs
[n
] = si
->dfs
[t
];
2053 /* Visit all the implicit predecessors. */
2054 EXECUTE_IF_IN_NONNULL_BITMAP (graph
->implicit_preds
[n
], 0, i
, bi
)
2056 unsigned int w
= si
->node_mapping
[i
];
2058 if (bitmap_bit_p (si
->deleted
, w
))
2061 if (!bitmap_bit_p (si
->visited
, w
))
2062 condense_visit (graph
, si
, w
);
2064 unsigned int t
= si
->node_mapping
[w
];
2065 gcc_assert (si
->node_mapping
[n
] == n
);
2066 if (si
->dfs
[t
] < si
->dfs
[n
])
2067 si
->dfs
[n
] = si
->dfs
[t
];
2070 /* See if any components have been identified. */
2071 if (si
->dfs
[n
] == my_dfs
)
2073 while (si
->scc_stack
.length () != 0
2074 && si
->dfs
[si
->scc_stack
.last ()] >= my_dfs
)
2076 unsigned int w
= si
->scc_stack
.pop ();
2077 si
->node_mapping
[w
] = n
;
2079 if (!bitmap_bit_p (graph
->direct_nodes
, w
))
2080 bitmap_clear_bit (graph
->direct_nodes
, n
);
2082 /* Unify our nodes. */
2083 if (graph
->preds
[w
])
2085 if (!graph
->preds
[n
])
2086 graph
->preds
[n
] = BITMAP_ALLOC (&predbitmap_obstack
);
2087 bitmap_ior_into (graph
->preds
[n
], graph
->preds
[w
]);
2089 if (graph
->implicit_preds
[w
])
2091 if (!graph
->implicit_preds
[n
])
2092 graph
->implicit_preds
[n
] = BITMAP_ALLOC (&predbitmap_obstack
);
2093 bitmap_ior_into (graph
->implicit_preds
[n
],
2094 graph
->implicit_preds
[w
]);
2096 if (graph
->points_to
[w
])
2098 if (!graph
->points_to
[n
])
2099 graph
->points_to
[n
] = BITMAP_ALLOC (&predbitmap_obstack
);
2100 bitmap_ior_into (graph
->points_to
[n
],
2101 graph
->points_to
[w
]);
2104 bitmap_set_bit (si
->deleted
, n
);
2107 si
->scc_stack
.safe_push (n
);
2110 /* Label pointer equivalences.
2112 This performs a value numbering of the constraint graph to
2113 discover which variables will always have the same points-to sets
2114 under the current set of constraints.
2116 The way it value numbers is to store the set of points-to bits
2117 generated by the constraints and graph edges. This is just used as a
2118 hash and equality comparison. The *actual set of points-to bits* is
2119 completely irrelevant, in that we don't care about being able to
2122 The equality values (currently bitmaps) just have to satisfy a few
2123 constraints, the main ones being:
2124 1. The combining operation must be order independent.
2125 2. The end result of a given set of operations must be unique iff the
2126 combination of input values is unique
2130 label_visit (constraint_graph_t graph
, struct scc_info
*si
, unsigned int n
)
2132 unsigned int i
, first_pred
;
2135 bitmap_set_bit (si
->visited
, n
);
2137 /* Label and union our incoming edges's points to sets. */
2139 EXECUTE_IF_IN_NONNULL_BITMAP (graph
->preds
[n
], 0, i
, bi
)
2141 unsigned int w
= si
->node_mapping
[i
];
2142 if (!bitmap_bit_p (si
->visited
, w
))
2143 label_visit (graph
, si
, w
);
2145 /* Skip unused edges */
2146 if (w
== n
|| graph
->pointer_label
[w
] == 0)
2149 if (graph
->points_to
[w
])
2151 if (!graph
->points_to
[n
])
2153 if (first_pred
== -1U)
2157 graph
->points_to
[n
] = BITMAP_ALLOC (&predbitmap_obstack
);
2158 bitmap_ior (graph
->points_to
[n
],
2159 graph
->points_to
[first_pred
],
2160 graph
->points_to
[w
]);
2164 bitmap_ior_into (graph
->points_to
[n
], graph
->points_to
[w
]);
2168 /* Indirect nodes get fresh variables and a new pointer equiv class. */
2169 if (!bitmap_bit_p (graph
->direct_nodes
, n
))
2171 if (!graph
->points_to
[n
])
2173 graph
->points_to
[n
] = BITMAP_ALLOC (&predbitmap_obstack
);
2174 if (first_pred
!= -1U)
2175 bitmap_copy (graph
->points_to
[n
], graph
->points_to
[first_pred
]);
2177 bitmap_set_bit (graph
->points_to
[n
], FIRST_REF_NODE
+ n
);
2178 graph
->pointer_label
[n
] = pointer_equiv_class
++;
2179 equiv_class_label_t ecl
;
2180 ecl
= equiv_class_lookup_or_add (pointer_equiv_class_table
,
2181 graph
->points_to
[n
]);
2182 ecl
->equivalence_class
= graph
->pointer_label
[n
];
2186 /* If there was only a single non-empty predecessor the pointer equiv
2187 class is the same. */
2188 if (!graph
->points_to
[n
])
2190 if (first_pred
!= -1U)
2192 graph
->pointer_label
[n
] = graph
->pointer_label
[first_pred
];
2193 graph
->points_to
[n
] = graph
->points_to
[first_pred
];
2198 if (!bitmap_empty_p (graph
->points_to
[n
]))
2200 equiv_class_label_t ecl
;
2201 ecl
= equiv_class_lookup_or_add (pointer_equiv_class_table
,
2202 graph
->points_to
[n
]);
2203 if (ecl
->equivalence_class
== 0)
2204 ecl
->equivalence_class
= pointer_equiv_class
++;
2207 BITMAP_FREE (graph
->points_to
[n
]);
2208 graph
->points_to
[n
] = ecl
->labels
;
2210 graph
->pointer_label
[n
] = ecl
->equivalence_class
;
2214 /* Print the pred graph in dot format. */
2217 dump_pred_graph (struct scc_info
*si
, FILE *file
)
2221 /* Only print the graph if it has already been initialized: */
2225 /* Prints the header of the dot file: */
2226 fprintf (file
, "strict digraph {\n");
2227 fprintf (file
, " node [\n shape = box\n ]\n");
2228 fprintf (file
, " edge [\n fontsize = \"12\"\n ]\n");
2229 fprintf (file
, "\n // List of nodes and complex constraints in "
2230 "the constraint graph:\n");
2232 /* The next lines print the nodes in the graph together with the
2233 complex constraints attached to them. */
2234 for (i
= 1; i
< graph
->size
; i
++)
2236 if (i
== FIRST_REF_NODE
)
2238 if (si
->node_mapping
[i
] != i
)
2240 if (i
< FIRST_REF_NODE
)
2241 fprintf (file
, "\"%s\"", get_varinfo (i
)->name
);
2243 fprintf (file
, "\"*%s\"", get_varinfo (i
- FIRST_REF_NODE
)->name
);
2244 if (graph
->points_to
[i
]
2245 && !bitmap_empty_p (graph
->points_to
[i
]))
2247 if (i
< FIRST_REF_NODE
)
2248 fprintf (file
, "[label=\"%s = {", get_varinfo (i
)->name
);
2250 fprintf (file
, "[label=\"*%s = {",
2251 get_varinfo (i
- FIRST_REF_NODE
)->name
);
2254 EXECUTE_IF_SET_IN_BITMAP (graph
->points_to
[i
], 0, j
, bi
)
2255 fprintf (file
, " %d", j
);
2256 fprintf (file
, " }\"]");
2258 fprintf (file
, ";\n");
2261 /* Go over the edges. */
2262 fprintf (file
, "\n // Edges in the constraint graph:\n");
2263 for (i
= 1; i
< graph
->size
; i
++)
2267 if (si
->node_mapping
[i
] != i
)
2269 EXECUTE_IF_IN_NONNULL_BITMAP (graph
->preds
[i
], 0, j
, bi
)
2271 unsigned from
= si
->node_mapping
[j
];
2272 if (from
< FIRST_REF_NODE
)
2273 fprintf (file
, "\"%s\"", get_varinfo (from
)->name
);
2275 fprintf (file
, "\"*%s\"", get_varinfo (from
- FIRST_REF_NODE
)->name
);
2276 fprintf (file
, " -> ");
2277 if (i
< FIRST_REF_NODE
)
2278 fprintf (file
, "\"%s\"", get_varinfo (i
)->name
);
2280 fprintf (file
, "\"*%s\"", get_varinfo (i
- FIRST_REF_NODE
)->name
);
2281 fprintf (file
, ";\n");
2285 /* Prints the tail of the dot file. */
2286 fprintf (file
, "}\n");
2289 /* Perform offline variable substitution, discovering equivalence
2290 classes, and eliminating non-pointer variables. */
2292 static struct scc_info
*
2293 perform_var_substitution (constraint_graph_t graph
)
2296 unsigned int size
= graph
->size
;
2297 scc_info
*si
= new scc_info (size
);
2299 bitmap_obstack_initialize (&iteration_obstack
);
2300 pointer_equiv_class_table
= new hash_table
<equiv_class_hasher
> (511);
2301 location_equiv_class_table
2302 = new hash_table
<equiv_class_hasher
> (511);
2303 pointer_equiv_class
= 1;
2304 location_equiv_class
= 1;
2306 /* Condense the nodes, which means to find SCC's, count incoming
2307 predecessors, and unite nodes in SCC's. */
2308 for (i
= 1; i
< FIRST_REF_NODE
; i
++)
2309 if (!bitmap_bit_p (si
->visited
, si
->node_mapping
[i
]))
2310 condense_visit (graph
, si
, si
->node_mapping
[i
]);
2312 if (dump_file
&& (dump_flags
& TDF_GRAPH
))
2314 fprintf (dump_file
, "\n\n// The constraint graph before var-substitution "
2315 "in dot format:\n");
2316 dump_pred_graph (si
, dump_file
);
2317 fprintf (dump_file
, "\n\n");
2320 bitmap_clear (si
->visited
);
2321 /* Actually the label the nodes for pointer equivalences */
2322 for (i
= 1; i
< FIRST_REF_NODE
; i
++)
2323 if (!bitmap_bit_p (si
->visited
, si
->node_mapping
[i
]))
2324 label_visit (graph
, si
, si
->node_mapping
[i
]);
2326 /* Calculate location equivalence labels. */
2327 for (i
= 1; i
< FIRST_REF_NODE
; i
++)
2333 if (!graph
->pointed_by
[i
])
2335 pointed_by
= BITMAP_ALLOC (&iteration_obstack
);
2337 /* Translate the pointed-by mapping for pointer equivalence
2339 EXECUTE_IF_SET_IN_BITMAP (graph
->pointed_by
[i
], 0, j
, bi
)
2341 bitmap_set_bit (pointed_by
,
2342 graph
->pointer_label
[si
->node_mapping
[j
]]);
2344 /* The original pointed_by is now dead. */
2345 BITMAP_FREE (graph
->pointed_by
[i
]);
2347 /* Look up the location equivalence label if one exists, or make
2349 equiv_class_label_t ecl
;
2350 ecl
= equiv_class_lookup_or_add (location_equiv_class_table
, pointed_by
);
2351 if (ecl
->equivalence_class
== 0)
2352 ecl
->equivalence_class
= location_equiv_class
++;
2355 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
2356 fprintf (dump_file
, "Found location equivalence for node %s\n",
2357 get_varinfo (i
)->name
);
2358 BITMAP_FREE (pointed_by
);
2360 graph
->loc_label
[i
] = ecl
->equivalence_class
;
2364 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
2365 for (i
= 1; i
< FIRST_REF_NODE
; i
++)
2367 unsigned j
= si
->node_mapping
[i
];
2370 fprintf (dump_file
, "%s node id %d ",
2371 bitmap_bit_p (graph
->direct_nodes
, i
)
2372 ? "Direct" : "Indirect", i
);
2373 if (i
< FIRST_REF_NODE
)
2374 fprintf (dump_file
, "\"%s\"", get_varinfo (i
)->name
);
2376 fprintf (dump_file
, "\"*%s\"",
2377 get_varinfo (i
- FIRST_REF_NODE
)->name
);
2378 fprintf (dump_file
, " mapped to SCC leader node id %d ", j
);
2379 if (j
< FIRST_REF_NODE
)
2380 fprintf (dump_file
, "\"%s\"\n", get_varinfo (j
)->name
);
2382 fprintf (dump_file
, "\"*%s\"\n",
2383 get_varinfo (j
- FIRST_REF_NODE
)->name
);
2388 "Equivalence classes for %s node id %d ",
2389 bitmap_bit_p (graph
->direct_nodes
, i
)
2390 ? "direct" : "indirect", i
);
2391 if (i
< FIRST_REF_NODE
)
2392 fprintf (dump_file
, "\"%s\"", get_varinfo (i
)->name
);
2394 fprintf (dump_file
, "\"*%s\"",
2395 get_varinfo (i
- FIRST_REF_NODE
)->name
);
2397 ": pointer %d, location %d\n",
2398 graph
->pointer_label
[i
], graph
->loc_label
[i
]);
2402 /* Quickly eliminate our non-pointer variables. */
2404 for (i
= 1; i
< FIRST_REF_NODE
; i
++)
2406 unsigned int node
= si
->node_mapping
[i
];
2408 if (graph
->pointer_label
[node
] == 0)
2410 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
2412 "%s is a non-pointer variable, eliminating edges.\n",
2413 get_varinfo (node
)->name
);
2414 stats
.nonpointer_vars
++;
2415 clear_edges_for_node (graph
, node
);
2422 /* Free information that was only necessary for variable
2426 free_var_substitution_info (struct scc_info
*si
)
2429 free (graph
->pointer_label
);
2430 free (graph
->loc_label
);
2431 free (graph
->pointed_by
);
2432 free (graph
->points_to
);
2433 free (graph
->eq_rep
);
2434 sbitmap_free (graph
->direct_nodes
);
2435 delete pointer_equiv_class_table
;
2436 pointer_equiv_class_table
= NULL
;
2437 delete location_equiv_class_table
;
2438 location_equiv_class_table
= NULL
;
2439 bitmap_obstack_release (&iteration_obstack
);
2442 /* Return an existing node that is equivalent to NODE, which has
2443 equivalence class LABEL, if one exists. Return NODE otherwise. */
2446 find_equivalent_node (constraint_graph_t graph
,
2447 unsigned int node
, unsigned int label
)
2449 /* If the address version of this variable is unused, we can
2450 substitute it for anything else with the same label.
2451 Otherwise, we know the pointers are equivalent, but not the
2452 locations, and we can unite them later. */
2454 if (!bitmap_bit_p (graph
->address_taken
, node
))
2456 gcc_checking_assert (label
< graph
->size
);
2458 if (graph
->eq_rep
[label
] != -1)
2460 /* Unify the two variables since we know they are equivalent. */
2461 if (unite (graph
->eq_rep
[label
], node
))
2462 unify_nodes (graph
, graph
->eq_rep
[label
], node
, false);
2463 return graph
->eq_rep
[label
];
2467 graph
->eq_rep
[label
] = node
;
2468 graph
->pe_rep
[label
] = node
;
2473 gcc_checking_assert (label
< graph
->size
);
2474 graph
->pe
[node
] = label
;
2475 if (graph
->pe_rep
[label
] == -1)
2476 graph
->pe_rep
[label
] = node
;
2482 /* Unite pointer equivalent but not location equivalent nodes in
2483 GRAPH. This may only be performed once variable substitution is
2487 unite_pointer_equivalences (constraint_graph_t graph
)
2491 /* Go through the pointer equivalences and unite them to their
2492 representative, if they aren't already. */
2493 for (i
= 1; i
< FIRST_REF_NODE
; i
++)
2495 unsigned int label
= graph
->pe
[i
];
2498 int label_rep
= graph
->pe_rep
[label
];
2500 if (label_rep
== -1)
2503 label_rep
= find (label_rep
);
2504 if (label_rep
>= 0 && unite (label_rep
, find (i
)))
2505 unify_nodes (graph
, label_rep
, i
, false);
2510 /* Move complex constraints to the GRAPH nodes they belong to. */
2513 move_complex_constraints (constraint_graph_t graph
)
2518 FOR_EACH_VEC_ELT (constraints
, i
, c
)
2522 struct constraint_expr lhs
= c
->lhs
;
2523 struct constraint_expr rhs
= c
->rhs
;
2525 if (lhs
.type
== DEREF
)
2527 insert_into_complex (graph
, lhs
.var
, c
);
2529 else if (rhs
.type
== DEREF
)
2531 if (!(get_varinfo (lhs
.var
)->is_special_var
))
2532 insert_into_complex (graph
, rhs
.var
, c
);
2534 else if (rhs
.type
!= ADDRESSOF
&& lhs
.var
> anything_id
2535 && (lhs
.offset
!= 0 || rhs
.offset
!= 0))
2537 insert_into_complex (graph
, rhs
.var
, c
);
2544 /* Optimize and rewrite complex constraints while performing
2545 collapsing of equivalent nodes. SI is the SCC_INFO that is the
2546 result of perform_variable_substitution. */
2549 rewrite_constraints (constraint_graph_t graph
,
2550 struct scc_info
*si
)
2557 for (unsigned int j
= 0; j
< graph
->size
; j
++)
2558 gcc_assert (find (j
) == j
);
2561 FOR_EACH_VEC_ELT (constraints
, i
, c
)
2563 struct constraint_expr lhs
= c
->lhs
;
2564 struct constraint_expr rhs
= c
->rhs
;
2565 unsigned int lhsvar
= find (lhs
.var
);
2566 unsigned int rhsvar
= find (rhs
.var
);
2567 unsigned int lhsnode
, rhsnode
;
2568 unsigned int lhslabel
, rhslabel
;
2570 lhsnode
= si
->node_mapping
[lhsvar
];
2571 rhsnode
= si
->node_mapping
[rhsvar
];
2572 lhslabel
= graph
->pointer_label
[lhsnode
];
2573 rhslabel
= graph
->pointer_label
[rhsnode
];
2575 /* See if it is really a non-pointer variable, and if so, ignore
2579 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
2582 fprintf (dump_file
, "%s is a non-pointer variable, "
2583 "ignoring constraint:",
2584 get_varinfo (lhs
.var
)->name
);
2585 dump_constraint (dump_file
, c
);
2586 fprintf (dump_file
, "\n");
2588 constraints
[i
] = NULL
;
2594 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
2597 fprintf (dump_file
, "%s is a non-pointer variable, "
2598 "ignoring constraint:",
2599 get_varinfo (rhs
.var
)->name
);
2600 dump_constraint (dump_file
, c
);
2601 fprintf (dump_file
, "\n");
2603 constraints
[i
] = NULL
;
2607 lhsvar
= find_equivalent_node (graph
, lhsvar
, lhslabel
);
2608 rhsvar
= find_equivalent_node (graph
, rhsvar
, rhslabel
);
2609 c
->lhs
.var
= lhsvar
;
2610 c
->rhs
.var
= rhsvar
;
2614 /* Eliminate indirect cycles involving NODE. Return true if NODE was
2615 part of an SCC, false otherwise. */
2618 eliminate_indirect_cycles (unsigned int node
)
2620 if (graph
->indirect_cycles
[node
] != -1
2621 && !bitmap_empty_p (get_varinfo (node
)->solution
))
2624 auto_vec
<unsigned> queue
;
2626 unsigned int to
= find (graph
->indirect_cycles
[node
]);
2629 /* We can't touch the solution set and call unify_nodes
2630 at the same time, because unify_nodes is going to do
2631 bitmap unions into it. */
2633 EXECUTE_IF_SET_IN_BITMAP (get_varinfo (node
)->solution
, 0, i
, bi
)
2635 if (find (i
) == i
&& i
!= to
)
2638 queue
.safe_push (i
);
2643 queue
.iterate (queuepos
, &i
);
2646 unify_nodes (graph
, to
, i
, true);
2653 /* Solve the constraint graph GRAPH using our worklist solver.
2654 This is based on the PW* family of solvers from the "Efficient Field
2655 Sensitive Pointer Analysis for C" paper.
2656 It works by iterating over all the graph nodes, processing the complex
2657 constraints and propagating the copy constraints, until everything stops
2658 changed. This corresponds to steps 6-8 in the solving list given above. */
2661 solve_graph (constraint_graph_t graph
)
2663 unsigned int size
= graph
->size
;
2667 changed
= BITMAP_ALLOC (NULL
);
2669 /* Mark all initial non-collapsed nodes as changed. */
2670 for (i
= 1; i
< size
; i
++)
2672 varinfo_t ivi
= get_varinfo (i
);
2673 if (find (i
) == i
&& !bitmap_empty_p (ivi
->solution
)
2674 && ((graph
->succs
[i
] && !bitmap_empty_p (graph
->succs
[i
]))
2675 || graph
->complex[i
].length () > 0))
2676 bitmap_set_bit (changed
, i
);
2679 /* Allocate a bitmap to be used to store the changed bits. */
2680 pts
= BITMAP_ALLOC (&pta_obstack
);
2682 while (!bitmap_empty_p (changed
))
2685 struct topo_info
*ti
= init_topo_info ();
2688 bitmap_obstack_initialize (&iteration_obstack
);
2690 compute_topo_order (graph
, ti
);
2692 while (ti
->topo_order
.length () != 0)
2695 i
= ti
->topo_order
.pop ();
2697 /* If this variable is not a representative, skip it. */
2701 /* In certain indirect cycle cases, we may merge this
2702 variable to another. */
2703 if (eliminate_indirect_cycles (i
) && find (i
) != i
)
2706 /* If the node has changed, we need to process the
2707 complex constraints and outgoing edges again. */
2708 if (bitmap_clear_bit (changed
, i
))
2713 vec
<constraint_t
> complex = graph
->complex[i
];
2714 varinfo_t vi
= get_varinfo (i
);
2715 bool solution_empty
;
2717 /* Compute the changed set of solution bits. If anything
2718 is in the solution just propagate that. */
2719 if (bitmap_bit_p (vi
->solution
, anything_id
))
2721 /* If anything is also in the old solution there is
2723 ??? But we shouldn't ended up with "changed" set ... */
2725 && bitmap_bit_p (vi
->oldsolution
, anything_id
))
2727 bitmap_copy (pts
, get_varinfo (find (anything_id
))->solution
);
2729 else if (vi
->oldsolution
)
2730 bitmap_and_compl (pts
, vi
->solution
, vi
->oldsolution
);
2732 bitmap_copy (pts
, vi
->solution
);
2734 if (bitmap_empty_p (pts
))
2737 if (vi
->oldsolution
)
2738 bitmap_ior_into (vi
->oldsolution
, pts
);
2741 vi
->oldsolution
= BITMAP_ALLOC (&oldpta_obstack
);
2742 bitmap_copy (vi
->oldsolution
, pts
);
2745 solution
= vi
->solution
;
2746 solution_empty
= bitmap_empty_p (solution
);
2748 /* Process the complex constraints */
2749 bitmap expanded_pts
= NULL
;
2750 FOR_EACH_VEC_ELT (complex, j
, c
)
2752 /* XXX: This is going to unsort the constraints in
2753 some cases, which will occasionally add duplicate
2754 constraints during unification. This does not
2755 affect correctness. */
2756 c
->lhs
.var
= find (c
->lhs
.var
);
2757 c
->rhs
.var
= find (c
->rhs
.var
);
2759 /* The only complex constraint that can change our
2760 solution to non-empty, given an empty solution,
2761 is a constraint where the lhs side is receiving
2762 some set from elsewhere. */
2763 if (!solution_empty
|| c
->lhs
.type
!= DEREF
)
2764 do_complex_constraint (graph
, c
, pts
, &expanded_pts
);
2766 BITMAP_FREE (expanded_pts
);
2768 solution_empty
= bitmap_empty_p (solution
);
2770 if (!solution_empty
)
2773 unsigned eff_escaped_id
= find (escaped_id
);
2775 /* Propagate solution to all successors. */
2776 unsigned to_remove
= ~0U;
2777 EXECUTE_IF_IN_NONNULL_BITMAP (graph
->succs
[i
],
2780 if (to_remove
!= ~0U)
2782 bitmap_clear_bit (graph
->succs
[i
], to_remove
);
2785 unsigned int to
= find (j
);
2788 /* Update the succ graph, avoiding duplicate
2791 if (! bitmap_set_bit (graph
->succs
[i
], to
))
2793 /* We eventually end up processing 'to' twice
2794 as it is undefined whether bitmap iteration
2795 iterates over bits set during iteration.
2796 Play safe instead of doing tricks. */
2798 /* Don't try to propagate to ourselves. */
2802 bitmap tmp
= get_varinfo (to
)->solution
;
2805 /* If we propagate from ESCAPED use ESCAPED as
2807 if (i
== eff_escaped_id
)
2808 flag
= bitmap_set_bit (tmp
, escaped_id
);
2810 flag
= bitmap_ior_into (tmp
, pts
);
2813 bitmap_set_bit (changed
, to
);
2815 if (to_remove
!= ~0U)
2816 bitmap_clear_bit (graph
->succs
[i
], to_remove
);
2820 free_topo_info (ti
);
2821 bitmap_obstack_release (&iteration_obstack
);
2825 BITMAP_FREE (changed
);
2826 bitmap_obstack_release (&oldpta_obstack
);
2829 /* Map from trees to variable infos. */
2830 static hash_map
<tree
, varinfo_t
> *vi_for_tree
;
2833 /* Insert ID as the variable id for tree T in the vi_for_tree map. */
2836 insert_vi_for_tree (tree t
, varinfo_t vi
)
2839 gcc_assert (!vi_for_tree
->put (t
, vi
));
2842 /* Find the variable info for tree T in VI_FOR_TREE. If T does not
2843 exist in the map, return NULL, otherwise, return the varinfo we found. */
2846 lookup_vi_for_tree (tree t
)
2848 varinfo_t
*slot
= vi_for_tree
->get (t
);
2855 /* Return a printable name for DECL */
2858 alias_get_name (tree decl
)
2860 const char *res
= "NULL";
2864 if (TREE_CODE (decl
) == SSA_NAME
)
2866 res
= get_name (decl
);
2867 temp
= xasprintf ("%s_%u", res
? res
: "", SSA_NAME_VERSION (decl
));
2869 else if (HAS_DECL_ASSEMBLER_NAME_P (decl
)
2870 && DECL_ASSEMBLER_NAME_SET_P (decl
))
2871 res
= IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME_RAW (decl
));
2872 else if (DECL_P (decl
))
2874 res
= get_name (decl
);
2876 temp
= xasprintf ("D.%u", DECL_UID (decl
));
2881 res
= ggc_strdup (temp
);
2889 /* Find the variable id for tree T in the map.
2890 If T doesn't exist in the map, create an entry for it and return it. */
2893 get_vi_for_tree (tree t
)
2895 varinfo_t
*slot
= vi_for_tree
->get (t
);
2898 unsigned int id
= create_variable_info_for (t
, alias_get_name (t
), false);
2899 return get_varinfo (id
);
2905 /* Get a scalar constraint expression for a new temporary variable. */
2907 static struct constraint_expr
2908 new_scalar_tmp_constraint_exp (const char *name
, bool add_id
)
2910 struct constraint_expr tmp
;
2913 vi
= new_var_info (NULL_TREE
, name
, add_id
);
2917 vi
->is_full_var
= 1;
2927 /* Get a constraint expression vector from an SSA_VAR_P node.
2928 If address_p is true, the result will be taken its address of. */
2931 get_constraint_for_ssa_var (tree t
, vec
<ce_s
> *results
, bool address_p
)
2933 struct constraint_expr cexpr
;
2936 /* We allow FUNCTION_DECLs here even though it doesn't make much sense. */
2937 gcc_assert (TREE_CODE (t
) == SSA_NAME
|| DECL_P (t
));
2939 if (TREE_CODE (t
) == SSA_NAME
2940 && SSA_NAME_IS_DEFAULT_DEF (t
))
2942 /* For parameters, get at the points-to set for the actual parm
2944 if (TREE_CODE (SSA_NAME_VAR (t
)) == PARM_DECL
2945 || TREE_CODE (SSA_NAME_VAR (t
)) == RESULT_DECL
)
2947 get_constraint_for_ssa_var (SSA_NAME_VAR (t
), results
, address_p
);
2950 /* For undefined SSA names return nothing. */
2951 else if (!ssa_defined_default_def_p (t
))
2953 cexpr
.var
= nothing_id
;
2954 cexpr
.type
= SCALAR
;
2956 results
->safe_push (cexpr
);
2961 /* For global variables resort to the alias target. */
2962 if (VAR_P (t
) && (TREE_STATIC (t
) || DECL_EXTERNAL (t
)))
2964 varpool_node
*node
= varpool_node::get (t
);
2965 if (node
&& node
->alias
&& node
->analyzed
)
2967 node
= node
->ultimate_alias_target ();
2968 /* Canonicalize the PT uid of all aliases to the ultimate target.
2969 ??? Hopefully the set of aliases can't change in a way that
2970 changes the ultimate alias target. */
2971 gcc_assert ((! DECL_PT_UID_SET_P (node
->decl
)
2972 || DECL_PT_UID (node
->decl
) == DECL_UID (node
->decl
))
2973 && (! DECL_PT_UID_SET_P (t
)
2974 || DECL_PT_UID (t
) == DECL_UID (node
->decl
)));
2975 DECL_PT_UID (t
) = DECL_UID (node
->decl
);
2979 /* If this is decl may bind to NULL note that. */
2981 && (! node
|| ! node
->nonzero_address ()))
2983 cexpr
.var
= nothing_id
;
2984 cexpr
.type
= SCALAR
;
2986 results
->safe_push (cexpr
);
2990 vi
= get_vi_for_tree (t
);
2992 cexpr
.type
= SCALAR
;
2995 /* If we are not taking the address of the constraint expr, add all
2996 sub-fiels of the variable as well. */
2998 && !vi
->is_full_var
)
3000 for (; vi
; vi
= vi_next (vi
))
3003 results
->safe_push (cexpr
);
3008 results
->safe_push (cexpr
);
3011 /* Process constraint T, performing various simplifications and then
3012 adding it to our list of overall constraints. */
3015 process_constraint (constraint_t t
)
3017 struct constraint_expr rhs
= t
->rhs
;
3018 struct constraint_expr lhs
= t
->lhs
;
3020 gcc_assert (rhs
.var
< varmap
.length ());
3021 gcc_assert (lhs
.var
< varmap
.length ());
3023 /* If we didn't get any useful constraint from the lhs we get
3024 &ANYTHING as fallback from get_constraint_for. Deal with
3025 it here by turning it into *ANYTHING. */
3026 if (lhs
.type
== ADDRESSOF
3027 && lhs
.var
== anything_id
)
3030 /* ADDRESSOF on the lhs is invalid. */
3031 gcc_assert (lhs
.type
!= ADDRESSOF
);
3033 /* We shouldn't add constraints from things that cannot have pointers.
3034 It's not completely trivial to avoid in the callers, so do it here. */
3035 if (rhs
.type
!= ADDRESSOF
3036 && !get_varinfo (rhs
.var
)->may_have_pointers
)
3039 /* Likewise adding to the solution of a non-pointer var isn't useful. */
3040 if (!get_varinfo (lhs
.var
)->may_have_pointers
)
3043 /* This can happen in our IR with things like n->a = *p */
3044 if (rhs
.type
== DEREF
&& lhs
.type
== DEREF
&& rhs
.var
!= anything_id
)
3046 /* Split into tmp = *rhs, *lhs = tmp */
3047 struct constraint_expr tmplhs
;
3048 tmplhs
= new_scalar_tmp_constraint_exp ("doubledereftmp", true);
3049 process_constraint (new_constraint (tmplhs
, rhs
));
3050 process_constraint (new_constraint (lhs
, tmplhs
));
3052 else if ((rhs
.type
!= SCALAR
|| rhs
.offset
!= 0) && lhs
.type
== DEREF
)
3054 /* Split into tmp = &rhs, *lhs = tmp */
3055 struct constraint_expr tmplhs
;
3056 tmplhs
= new_scalar_tmp_constraint_exp ("derefaddrtmp", true);
3057 process_constraint (new_constraint (tmplhs
, rhs
));
3058 process_constraint (new_constraint (lhs
, tmplhs
));
3062 gcc_assert (rhs
.type
!= ADDRESSOF
|| rhs
.offset
== 0);
3063 constraints
.safe_push (t
);
3068 /* Return the position, in bits, of FIELD_DECL from the beginning of its
3071 static HOST_WIDE_INT
3072 bitpos_of_field (const tree fdecl
)
3074 if (!tree_fits_shwi_p (DECL_FIELD_OFFSET (fdecl
))
3075 || !tree_fits_shwi_p (DECL_FIELD_BIT_OFFSET (fdecl
)))
3078 return (tree_to_shwi (DECL_FIELD_OFFSET (fdecl
)) * BITS_PER_UNIT
3079 + tree_to_shwi (DECL_FIELD_BIT_OFFSET (fdecl
)));
3083 /* Get constraint expressions for offsetting PTR by OFFSET. Stores the
3084 resulting constraint expressions in *RESULTS. */
3087 get_constraint_for_ptr_offset (tree ptr
, tree offset
,
3090 struct constraint_expr c
;
3092 HOST_WIDE_INT rhsoffset
;
3094 /* If we do not do field-sensitive PTA adding offsets to pointers
3095 does not change the points-to solution. */
3096 if (!use_field_sensitive
)
3098 get_constraint_for_rhs (ptr
, results
);
3102 /* If the offset is not a non-negative integer constant that fits
3103 in a HOST_WIDE_INT, we have to fall back to a conservative
3104 solution which includes all sub-fields of all pointed-to
3105 variables of ptr. */
3106 if (offset
== NULL_TREE
3107 || TREE_CODE (offset
) != INTEGER_CST
)
3108 rhsoffset
= UNKNOWN_OFFSET
;
3111 /* Sign-extend the offset. */
3112 offset_int soffset
= offset_int::from (wi::to_wide (offset
), SIGNED
);
3113 if (!wi::fits_shwi_p (soffset
))
3114 rhsoffset
= UNKNOWN_OFFSET
;
3117 /* Make sure the bit-offset also fits. */
3118 HOST_WIDE_INT rhsunitoffset
= soffset
.to_shwi ();
3119 rhsoffset
= rhsunitoffset
* (unsigned HOST_WIDE_INT
) BITS_PER_UNIT
;
3120 if (rhsunitoffset
!= rhsoffset
/ BITS_PER_UNIT
)
3121 rhsoffset
= UNKNOWN_OFFSET
;
3125 get_constraint_for_rhs (ptr
, results
);
3129 /* As we are eventually appending to the solution do not use
3130 vec::iterate here. */
3131 n
= results
->length ();
3132 for (j
= 0; j
< n
; j
++)
3136 curr
= get_varinfo (c
.var
);
3138 if (c
.type
== ADDRESSOF
3139 /* If this varinfo represents a full variable just use it. */
3140 && curr
->is_full_var
)
3142 else if (c
.type
== ADDRESSOF
3143 /* If we do not know the offset add all subfields. */
3144 && rhsoffset
== UNKNOWN_OFFSET
)
3146 varinfo_t temp
= get_varinfo (curr
->head
);
3149 struct constraint_expr c2
;
3151 c2
.type
= ADDRESSOF
;
3153 if (c2
.var
!= c
.var
)
3154 results
->safe_push (c2
);
3155 temp
= vi_next (temp
);
3159 else if (c
.type
== ADDRESSOF
)
3162 unsigned HOST_WIDE_INT offset
= curr
->offset
+ rhsoffset
;
3164 /* If curr->offset + rhsoffset is less than zero adjust it. */
3166 && curr
->offset
< offset
)
3169 /* We have to include all fields that overlap the current
3170 field shifted by rhsoffset. And we include at least
3171 the last or the first field of the variable to represent
3172 reachability of off-bound addresses, in particular &object + 1,
3173 conservatively correct. */
3174 temp
= first_or_preceding_vi_for_offset (curr
, offset
);
3177 temp
= vi_next (temp
);
3179 && temp
->offset
< offset
+ curr
->size
)
3181 struct constraint_expr c2
;
3183 c2
.type
= ADDRESSOF
;
3185 results
->safe_push (c2
);
3186 temp
= vi_next (temp
);
3189 else if (c
.type
== SCALAR
)
3191 gcc_assert (c
.offset
== 0);
3192 c
.offset
= rhsoffset
;
3195 /* We shouldn't get any DEREFs here. */
3203 /* Given a COMPONENT_REF T, return the constraint_expr vector for it.
3204 If address_p is true the result will be taken its address of.
3205 If lhs_p is true then the constraint expression is assumed to be used
3209 get_constraint_for_component_ref (tree t
, vec
<ce_s
> *results
,
3210 bool address_p
, bool lhs_p
)
3213 poly_int64 bitsize
= -1;
3214 poly_int64 bitmaxsize
= -1;
3219 /* Some people like to do cute things like take the address of
3222 while (handled_component_p (forzero
)
3223 || INDIRECT_REF_P (forzero
)
3224 || TREE_CODE (forzero
) == MEM_REF
)
3225 forzero
= TREE_OPERAND (forzero
, 0);
3227 if (CONSTANT_CLASS_P (forzero
) && integer_zerop (forzero
))
3229 struct constraint_expr temp
;
3232 temp
.var
= integer_id
;
3234 results
->safe_push (temp
);
3238 t
= get_ref_base_and_extent (t
, &bitpos
, &bitsize
, &bitmaxsize
, &reverse
);
3240 /* We can end up here for component references on a
3241 VIEW_CONVERT_EXPR <>(&foobar) or things like a
3242 BIT_FIELD_REF <&MEM[(void *)&b + 4B], ...>. So for
3243 symbolic constants simply give up. */
3244 if (TREE_CODE (t
) == ADDR_EXPR
)
3246 constraint_expr result
;
3247 result
.type
= SCALAR
;
3248 result
.var
= anything_id
;
3250 results
->safe_push (result
);
3254 /* Pretend to take the address of the base, we'll take care of
3255 adding the required subset of sub-fields below. */
3256 get_constraint_for_1 (t
, results
, true, lhs_p
);
3257 /* Strip off nothing_id. */
3258 if (results
->length () == 2)
3260 gcc_assert ((*results
)[0].var
== nothing_id
);
3261 results
->unordered_remove (0);
3263 gcc_assert (results
->length () == 1);
3264 struct constraint_expr
&result
= results
->last ();
3266 if (result
.type
== SCALAR
3267 && get_varinfo (result
.var
)->is_full_var
)
3268 /* For single-field vars do not bother about the offset. */
3270 else if (result
.type
== SCALAR
)
3272 /* In languages like C, you can access one past the end of an
3273 array. You aren't allowed to dereference it, so we can
3274 ignore this constraint. When we handle pointer subtraction,
3275 we may have to do something cute here. */
3277 if (maybe_lt (poly_uint64 (bitpos
), get_varinfo (result
.var
)->fullsize
)
3278 && maybe_ne (bitmaxsize
, 0))
3280 /* It's also not true that the constraint will actually start at the
3281 right offset, it may start in some padding. We only care about
3282 setting the constraint to the first actual field it touches, so
3284 struct constraint_expr cexpr
= result
;
3288 for (curr
= get_varinfo (cexpr
.var
); curr
; curr
= vi_next (curr
))
3290 if (ranges_maybe_overlap_p (poly_int64 (curr
->offset
),
3291 curr
->size
, bitpos
, bitmaxsize
))
3293 cexpr
.var
= curr
->id
;
3294 results
->safe_push (cexpr
);
3299 /* If we are going to take the address of this field then
3300 to be able to compute reachability correctly add at least
3301 the last field of the variable. */
3302 if (address_p
&& results
->length () == 0)
3304 curr
= get_varinfo (cexpr
.var
);
3305 while (curr
->next
!= 0)
3306 curr
= vi_next (curr
);
3307 cexpr
.var
= curr
->id
;
3308 results
->safe_push (cexpr
);
3310 else if (results
->length () == 0)
3311 /* Assert that we found *some* field there. The user couldn't be
3312 accessing *only* padding. */
3313 /* Still the user could access one past the end of an array
3314 embedded in a struct resulting in accessing *only* padding. */
3315 /* Or accessing only padding via type-punning to a type
3316 that has a filed just in padding space. */
3318 cexpr
.type
= SCALAR
;
3319 cexpr
.var
= anything_id
;
3321 results
->safe_push (cexpr
);
3324 else if (known_eq (bitmaxsize
, 0))
3326 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
3327 fprintf (dump_file
, "Access to zero-sized part of variable, "
3331 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
3332 fprintf (dump_file
, "Access to past the end of variable, ignoring\n");
3334 else if (result
.type
== DEREF
)
3336 /* If we do not know exactly where the access goes say so. Note
3337 that only for non-structure accesses we know that we access
3338 at most one subfiled of any variable. */
3339 HOST_WIDE_INT const_bitpos
;
3340 if (!bitpos
.is_constant (&const_bitpos
)
3341 || const_bitpos
== -1
3342 || maybe_ne (bitsize
, bitmaxsize
)
3343 || AGGREGATE_TYPE_P (TREE_TYPE (orig_t
))
3344 || result
.offset
== UNKNOWN_OFFSET
)
3345 result
.offset
= UNKNOWN_OFFSET
;
3347 result
.offset
+= const_bitpos
;
3349 else if (result
.type
== ADDRESSOF
)
3351 /* We can end up here for component references on constants like
3352 VIEW_CONVERT_EXPR <>({ 0, 1, 2, 3 })[i]. */
3353 result
.type
= SCALAR
;
3354 result
.var
= anything_id
;
3362 /* Dereference the constraint expression CONS, and return the result.
3363 DEREF (ADDRESSOF) = SCALAR
3364 DEREF (SCALAR) = DEREF
3365 DEREF (DEREF) = (temp = DEREF1; result = DEREF(temp))
3366 This is needed so that we can handle dereferencing DEREF constraints. */
3369 do_deref (vec
<ce_s
> *constraints
)
3371 struct constraint_expr
*c
;
3374 FOR_EACH_VEC_ELT (*constraints
, i
, c
)
3376 if (c
->type
== SCALAR
)
3378 else if (c
->type
== ADDRESSOF
)
3380 else if (c
->type
== DEREF
)
3382 struct constraint_expr tmplhs
;
3383 tmplhs
= new_scalar_tmp_constraint_exp ("dereftmp", true);
3384 process_constraint (new_constraint (tmplhs
, *c
));
3385 c
->var
= tmplhs
.var
;
3392 /* Given a tree T, return the constraint expression for taking the
3396 get_constraint_for_address_of (tree t
, vec
<ce_s
> *results
)
3398 struct constraint_expr
*c
;
3401 get_constraint_for_1 (t
, results
, true, true);
3403 FOR_EACH_VEC_ELT (*results
, i
, c
)
3405 if (c
->type
== DEREF
)
3408 c
->type
= ADDRESSOF
;
3412 /* Given a tree T, return the constraint expression for it. */
3415 get_constraint_for_1 (tree t
, vec
<ce_s
> *results
, bool address_p
,
3418 struct constraint_expr temp
;
3420 /* x = integer is all glommed to a single variable, which doesn't
3421 point to anything by itself. That is, of course, unless it is an
3422 integer constant being treated as a pointer, in which case, we
3423 will return that this is really the addressof anything. This
3424 happens below, since it will fall into the default case. The only
3425 case we know something about an integer treated like a pointer is
3426 when it is the NULL pointer, and then we just say it points to
3429 Do not do that if -fno-delete-null-pointer-checks though, because
3430 in that case *NULL does not fail, so it _should_ alias *anything.
3431 It is not worth adding a new option or renaming the existing one,
3432 since this case is relatively obscure. */
3433 if ((TREE_CODE (t
) == INTEGER_CST
3434 && integer_zerop (t
))
3435 /* The only valid CONSTRUCTORs in gimple with pointer typed
3436 elements are zero-initializer. But in IPA mode we also
3437 process global initializers, so verify at least. */
3438 || (TREE_CODE (t
) == CONSTRUCTOR
3439 && CONSTRUCTOR_NELTS (t
) == 0))
3441 if (flag_delete_null_pointer_checks
)
3442 temp
.var
= nothing_id
;
3444 temp
.var
= nonlocal_id
;
3445 temp
.type
= ADDRESSOF
;
3447 results
->safe_push (temp
);
3451 /* String constants are read-only, ideally we'd have a CONST_DECL
3453 if (TREE_CODE (t
) == STRING_CST
)
3455 temp
.var
= string_id
;
3458 results
->safe_push (temp
);
3462 switch (TREE_CODE_CLASS (TREE_CODE (t
)))
3464 case tcc_expression
:
3466 switch (TREE_CODE (t
))
3469 get_constraint_for_address_of (TREE_OPERAND (t
, 0), results
);
3477 switch (TREE_CODE (t
))
3481 struct constraint_expr cs
;
3483 get_constraint_for_ptr_offset (TREE_OPERAND (t
, 0),
3484 TREE_OPERAND (t
, 1), results
);
3487 /* If we are not taking the address then make sure to process
3488 all subvariables we might access. */
3492 cs
= results
->last ();
3493 if (cs
.type
== DEREF
3494 && type_can_have_subvars (TREE_TYPE (t
)))
3496 /* For dereferences this means we have to defer it
3498 results
->last ().offset
= UNKNOWN_OFFSET
;
3501 if (cs
.type
!= SCALAR
)
3504 vi
= get_varinfo (cs
.var
);
3505 curr
= vi_next (vi
);
3506 if (!vi
->is_full_var
3509 unsigned HOST_WIDE_INT size
;
3510 if (tree_fits_uhwi_p (TYPE_SIZE (TREE_TYPE (t
))))
3511 size
= tree_to_uhwi (TYPE_SIZE (TREE_TYPE (t
)));
3514 for (; curr
; curr
= vi_next (curr
))
3516 if (curr
->offset
- vi
->offset
< size
)
3519 results
->safe_push (cs
);
3528 case ARRAY_RANGE_REF
:
3533 get_constraint_for_component_ref (t
, results
, address_p
, lhs_p
);
3535 case VIEW_CONVERT_EXPR
:
3536 get_constraint_for_1 (TREE_OPERAND (t
, 0), results
, address_p
,
3539 /* We are missing handling for TARGET_MEM_REF here. */
3544 case tcc_exceptional
:
3546 switch (TREE_CODE (t
))
3550 get_constraint_for_ssa_var (t
, results
, address_p
);
3558 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (t
), i
, val
)
3560 struct constraint_expr
*rhsp
;
3562 get_constraint_for_1 (val
, &tmp
, address_p
, lhs_p
);
3563 FOR_EACH_VEC_ELT (tmp
, j
, rhsp
)
3564 results
->safe_push (*rhsp
);
3567 /* We do not know whether the constructor was complete,
3568 so technically we have to add &NOTHING or &ANYTHING
3569 like we do for an empty constructor as well. */
3576 case tcc_declaration
:
3578 get_constraint_for_ssa_var (t
, results
, address_p
);
3583 /* We cannot refer to automatic variables through constants. */
3584 temp
.type
= ADDRESSOF
;
3585 temp
.var
= nonlocal_id
;
3587 results
->safe_push (temp
);
3593 /* The default fallback is a constraint from anything. */
3594 temp
.type
= ADDRESSOF
;
3595 temp
.var
= anything_id
;
3597 results
->safe_push (temp
);
3600 /* Given a gimple tree T, return the constraint expression vector for it. */
3603 get_constraint_for (tree t
, vec
<ce_s
> *results
)
3605 gcc_assert (results
->length () == 0);
3607 get_constraint_for_1 (t
, results
, false, true);
3610 /* Given a gimple tree T, return the constraint expression vector for it
3611 to be used as the rhs of a constraint. */
3614 get_constraint_for_rhs (tree t
, vec
<ce_s
> *results
)
3616 gcc_assert (results
->length () == 0);
3618 get_constraint_for_1 (t
, results
, false, false);
3622 /* Efficiently generates constraints from all entries in *RHSC to all
3623 entries in *LHSC. */
3626 process_all_all_constraints (vec
<ce_s
> lhsc
,
3629 struct constraint_expr
*lhsp
, *rhsp
;
3632 if (lhsc
.length () <= 1 || rhsc
.length () <= 1)
3634 FOR_EACH_VEC_ELT (lhsc
, i
, lhsp
)
3635 FOR_EACH_VEC_ELT (rhsc
, j
, rhsp
)
3636 process_constraint (new_constraint (*lhsp
, *rhsp
));
3640 struct constraint_expr tmp
;
3641 tmp
= new_scalar_tmp_constraint_exp ("allalltmp", true);
3642 FOR_EACH_VEC_ELT (rhsc
, i
, rhsp
)
3643 process_constraint (new_constraint (tmp
, *rhsp
));
3644 FOR_EACH_VEC_ELT (lhsc
, i
, lhsp
)
3645 process_constraint (new_constraint (*lhsp
, tmp
));
3649 /* Handle aggregate copies by expanding into copies of the respective
3650 fields of the structures. */
3653 do_structure_copy (tree lhsop
, tree rhsop
)
3655 struct constraint_expr
*lhsp
, *rhsp
;
3656 auto_vec
<ce_s
> lhsc
;
3657 auto_vec
<ce_s
> rhsc
;
3660 get_constraint_for (lhsop
, &lhsc
);
3661 get_constraint_for_rhs (rhsop
, &rhsc
);
3664 if (lhsp
->type
== DEREF
3665 || (lhsp
->type
== ADDRESSOF
&& lhsp
->var
== anything_id
)
3666 || rhsp
->type
== DEREF
)
3668 if (lhsp
->type
== DEREF
)
3670 gcc_assert (lhsc
.length () == 1);
3671 lhsp
->offset
= UNKNOWN_OFFSET
;
3673 if (rhsp
->type
== DEREF
)
3675 gcc_assert (rhsc
.length () == 1);
3676 rhsp
->offset
= UNKNOWN_OFFSET
;
3678 process_all_all_constraints (lhsc
, rhsc
);
3680 else if (lhsp
->type
== SCALAR
3681 && (rhsp
->type
== SCALAR
3682 || rhsp
->type
== ADDRESSOF
))
3684 HOST_WIDE_INT lhssize
, lhsoffset
;
3685 HOST_WIDE_INT rhssize
, rhsoffset
;
3688 if (!get_ref_base_and_extent_hwi (lhsop
, &lhsoffset
, &lhssize
, &reverse
)
3689 || !get_ref_base_and_extent_hwi (rhsop
, &rhsoffset
, &rhssize
,
3692 process_all_all_constraints (lhsc
, rhsc
);
3695 for (j
= 0; lhsc
.iterate (j
, &lhsp
);)
3697 varinfo_t lhsv
, rhsv
;
3699 lhsv
= get_varinfo (lhsp
->var
);
3700 rhsv
= get_varinfo (rhsp
->var
);
3701 if (lhsv
->may_have_pointers
3702 && (lhsv
->is_full_var
3703 || rhsv
->is_full_var
3704 || ranges_overlap_p (lhsv
->offset
+ rhsoffset
, lhsv
->size
,
3705 rhsv
->offset
+ lhsoffset
, rhsv
->size
)))
3706 process_constraint (new_constraint (*lhsp
, *rhsp
));
3707 if (!rhsv
->is_full_var
3708 && (lhsv
->is_full_var
3709 || (lhsv
->offset
+ rhsoffset
+ lhsv
->size
3710 > rhsv
->offset
+ lhsoffset
+ rhsv
->size
)))
3713 if (k
>= rhsc
.length ())
3724 /* Create constraints ID = { rhsc }. */
3727 make_constraints_to (unsigned id
, vec
<ce_s
> rhsc
)
3729 struct constraint_expr
*c
;
3730 struct constraint_expr includes
;
3734 includes
.offset
= 0;
3735 includes
.type
= SCALAR
;
3737 FOR_EACH_VEC_ELT (rhsc
, j
, c
)
3738 process_constraint (new_constraint (includes
, *c
));
3741 /* Create a constraint ID = OP. */
3744 make_constraint_to (unsigned id
, tree op
)
3746 auto_vec
<ce_s
> rhsc
;
3747 get_constraint_for_rhs (op
, &rhsc
);
3748 make_constraints_to (id
, rhsc
);
3751 /* Create a constraint ID = &FROM. */
3754 make_constraint_from (varinfo_t vi
, int from
)
3756 struct constraint_expr lhs
, rhs
;
3764 rhs
.type
= ADDRESSOF
;
3765 process_constraint (new_constraint (lhs
, rhs
));
3768 /* Create a constraint ID = FROM. */
3771 make_copy_constraint (varinfo_t vi
, int from
)
3773 struct constraint_expr lhs
, rhs
;
3782 process_constraint (new_constraint (lhs
, rhs
));
3785 /* Make constraints necessary to make OP escape. */
3788 make_escape_constraint (tree op
)
3790 make_constraint_to (escaped_id
, op
);
3793 /* Add constraints to that the solution of VI is transitively closed. */
3796 make_transitive_closure_constraints (varinfo_t vi
)
3798 struct constraint_expr lhs
, rhs
;
3800 /* VAR = *(VAR + UNKNOWN); */
3806 rhs
.offset
= UNKNOWN_OFFSET
;
3807 process_constraint (new_constraint (lhs
, rhs
));
3810 /* Add constraints to that the solution of VI has all subvariables added. */
3813 make_any_offset_constraints (varinfo_t vi
)
3815 struct constraint_expr lhs
, rhs
;
3817 /* VAR = VAR + UNKNOWN; */
3823 rhs
.offset
= UNKNOWN_OFFSET
;
3824 process_constraint (new_constraint (lhs
, rhs
));
3827 /* Temporary storage for fake var decls. */
3828 struct obstack fake_var_decl_obstack
;
3830 /* Build a fake VAR_DECL acting as referrer to a DECL_UID. */
3833 build_fake_var_decl (tree type
)
3835 tree decl
= (tree
) XOBNEW (&fake_var_decl_obstack
, struct tree_var_decl
);
3836 memset (decl
, 0, sizeof (struct tree_var_decl
));
3837 TREE_SET_CODE (decl
, VAR_DECL
);
3838 TREE_TYPE (decl
) = type
;
3839 DECL_UID (decl
) = allocate_decl_uid ();
3840 SET_DECL_PT_UID (decl
, -1);
3841 layout_decl (decl
, 0);
3845 /* Create a new artificial heap variable with NAME.
3846 Return the created variable. */
3849 make_heapvar (const char *name
, bool add_id
)
3854 heapvar
= build_fake_var_decl (ptr_type_node
);
3855 DECL_EXTERNAL (heapvar
) = 1;
3857 vi
= new_var_info (heapvar
, name
, add_id
);
3858 vi
->is_heap_var
= true;
3859 vi
->is_unknown_size_var
= true;
3863 vi
->is_full_var
= true;
3864 insert_vi_for_tree (heapvar
, vi
);
3869 /* Create a new artificial heap variable with NAME and make a
3870 constraint from it to LHS. Set flags according to a tag used
3871 for tracking restrict pointers. */
3874 make_constraint_from_restrict (varinfo_t lhs
, const char *name
, bool add_id
)
3876 varinfo_t vi
= make_heapvar (name
, add_id
);
3877 vi
->is_restrict_var
= 1;
3878 vi
->is_global_var
= 1;
3879 vi
->may_have_pointers
= 1;
3880 make_constraint_from (lhs
, vi
->id
);
3884 /* Create a new artificial heap variable with NAME and make a
3885 constraint from it to LHS. Set flags according to a tag used
3886 for tracking restrict pointers and make the artificial heap
3887 point to global memory. */
3890 make_constraint_from_global_restrict (varinfo_t lhs
, const char *name
,
3893 varinfo_t vi
= make_constraint_from_restrict (lhs
, name
, add_id
);
3894 make_copy_constraint (vi
, nonlocal_id
);
3898 /* In IPA mode there are varinfos for different aspects of reach
3899 function designator. One for the points-to set of the return
3900 value, one for the variables that are clobbered by the function,
3901 one for its uses and one for each parameter (including a single
3902 glob for remaining variadic arguments). */
3904 enum { fi_clobbers
= 1, fi_uses
= 2,
3905 fi_static_chain
= 3, fi_result
= 4, fi_parm_base
= 5 };
3907 /* Get a constraint for the requested part of a function designator FI
3908 when operating in IPA mode. */
3910 static struct constraint_expr
3911 get_function_part_constraint (varinfo_t fi
, unsigned part
)
3913 struct constraint_expr c
;
3915 gcc_assert (in_ipa_mode
);
3917 if (fi
->id
== anything_id
)
3919 /* ??? We probably should have a ANYFN special variable. */
3920 c
.var
= anything_id
;
3924 else if (fi
->decl
&& TREE_CODE (fi
->decl
) == FUNCTION_DECL
)
3926 varinfo_t ai
= first_vi_for_offset (fi
, part
);
3930 c
.var
= anything_id
;
3944 /* For non-IPA mode, generate constraints necessary for a call on the
3948 handle_rhs_call (gcall
*stmt
, vec
<ce_s
> *results
)
3950 struct constraint_expr rhsc
;
3952 bool returns_uses
= false;
3954 for (i
= 0; i
< gimple_call_num_args (stmt
); ++i
)
3956 tree arg
= gimple_call_arg (stmt
, i
);
3957 int flags
= gimple_call_arg_flags (stmt
, i
);
3959 /* If the argument is not used we can ignore it. */
3960 if (flags
& EAF_UNUSED
)
3963 /* As we compute ESCAPED context-insensitive we do not gain
3964 any precision with just EAF_NOCLOBBER but not EAF_NOESCAPE
3965 set. The argument would still get clobbered through the
3967 if ((flags
& EAF_NOCLOBBER
)
3968 && (flags
& EAF_NOESCAPE
))
3970 varinfo_t uses
= get_call_use_vi (stmt
);
3971 varinfo_t tem
= new_var_info (NULL_TREE
, "callarg", true);
3972 tem
->is_reg_var
= true;
3973 make_constraint_to (tem
->id
, arg
);
3974 make_any_offset_constraints (tem
);
3975 if (!(flags
& EAF_DIRECT
))
3976 make_transitive_closure_constraints (tem
);
3977 make_copy_constraint (uses
, tem
->id
);
3978 returns_uses
= true;
3980 else if (flags
& EAF_NOESCAPE
)
3982 struct constraint_expr lhs
, rhs
;
3983 varinfo_t uses
= get_call_use_vi (stmt
);
3984 varinfo_t clobbers
= get_call_clobber_vi (stmt
);
3985 varinfo_t tem
= new_var_info (NULL_TREE
, "callarg", true);
3986 tem
->is_reg_var
= true;
3987 make_constraint_to (tem
->id
, arg
);
3988 make_any_offset_constraints (tem
);
3989 if (!(flags
& EAF_DIRECT
))
3990 make_transitive_closure_constraints (tem
);
3991 make_copy_constraint (uses
, tem
->id
);
3992 make_copy_constraint (clobbers
, tem
->id
);
3993 /* Add *tem = nonlocal, do not add *tem = callused as
3994 EAF_NOESCAPE parameters do not escape to other parameters
3995 and all other uses appear in NONLOCAL as well. */
4000 rhs
.var
= nonlocal_id
;
4002 process_constraint (new_constraint (lhs
, rhs
));
4003 returns_uses
= true;
4006 make_escape_constraint (arg
);
4009 /* If we added to the calls uses solution make sure we account for
4010 pointers to it to be returned. */
4013 rhsc
.var
= get_call_use_vi (stmt
)->id
;
4014 rhsc
.offset
= UNKNOWN_OFFSET
;
4016 results
->safe_push (rhsc
);
4019 /* The static chain escapes as well. */
4020 if (gimple_call_chain (stmt
))
4021 make_escape_constraint (gimple_call_chain (stmt
));
4023 /* And if we applied NRV the address of the return slot escapes as well. */
4024 if (gimple_call_return_slot_opt_p (stmt
)
4025 && gimple_call_lhs (stmt
) != NULL_TREE
4026 && TREE_ADDRESSABLE (TREE_TYPE (gimple_call_lhs (stmt
))))
4028 auto_vec
<ce_s
> tmpc
;
4029 struct constraint_expr lhsc
, *c
;
4030 get_constraint_for_address_of (gimple_call_lhs (stmt
), &tmpc
);
4031 lhsc
.var
= escaped_id
;
4034 FOR_EACH_VEC_ELT (tmpc
, i
, c
)
4035 process_constraint (new_constraint (lhsc
, *c
));
4038 /* Regular functions return nonlocal memory. */
4039 rhsc
.var
= nonlocal_id
;
4042 results
->safe_push (rhsc
);
4045 /* For non-IPA mode, generate constraints necessary for a call
4046 that returns a pointer and assigns it to LHS. This simply makes
4047 the LHS point to global and escaped variables. */
4050 handle_lhs_call (gcall
*stmt
, tree lhs
, int flags
, vec
<ce_s
> rhsc
,
4053 auto_vec
<ce_s
> lhsc
;
4055 get_constraint_for (lhs
, &lhsc
);
4056 /* If the store is to a global decl make sure to
4057 add proper escape constraints. */
4058 lhs
= get_base_address (lhs
);
4061 && is_global_var (lhs
))
4063 struct constraint_expr tmpc
;
4064 tmpc
.var
= escaped_id
;
4067 lhsc
.safe_push (tmpc
);
4070 /* If the call returns an argument unmodified override the rhs
4072 if (flags
& ERF_RETURNS_ARG
4073 && (flags
& ERF_RETURN_ARG_MASK
) < gimple_call_num_args (stmt
))
4077 arg
= gimple_call_arg (stmt
, flags
& ERF_RETURN_ARG_MASK
);
4078 get_constraint_for (arg
, &rhsc
);
4079 process_all_all_constraints (lhsc
, rhsc
);
4082 else if (flags
& ERF_NOALIAS
)
4085 struct constraint_expr tmpc
;
4087 vi
= make_heapvar ("HEAP", true);
4088 /* We are marking allocated storage local, we deal with it becoming
4089 global by escaping and setting of vars_contains_escaped_heap. */
4090 DECL_EXTERNAL (vi
->decl
) = 0;
4091 vi
->is_global_var
= 0;
4092 /* If this is not a real malloc call assume the memory was
4093 initialized and thus may point to global memory. All
4094 builtin functions with the malloc attribute behave in a sane way. */
4096 || !fndecl_built_in_p (fndecl
, BUILT_IN_NORMAL
))
4097 make_constraint_from (vi
, nonlocal_id
);
4100 tmpc
.type
= ADDRESSOF
;
4101 rhsc
.safe_push (tmpc
);
4102 process_all_all_constraints (lhsc
, rhsc
);
4106 process_all_all_constraints (lhsc
, rhsc
);
4109 /* For non-IPA mode, generate constraints necessary for a call of a
4110 const function that returns a pointer in the statement STMT. */
4113 handle_const_call (gcall
*stmt
, vec
<ce_s
> *results
)
4115 struct constraint_expr rhsc
;
4117 bool need_uses
= false;
4119 /* Treat nested const functions the same as pure functions as far
4120 as the static chain is concerned. */
4121 if (gimple_call_chain (stmt
))
4123 varinfo_t uses
= get_call_use_vi (stmt
);
4124 make_constraint_to (uses
->id
, gimple_call_chain (stmt
));
4128 /* And if we applied NRV the address of the return slot escapes as well. */
4129 if (gimple_call_return_slot_opt_p (stmt
)
4130 && gimple_call_lhs (stmt
) != NULL_TREE
4131 && TREE_ADDRESSABLE (TREE_TYPE (gimple_call_lhs (stmt
))))
4133 varinfo_t uses
= get_call_use_vi (stmt
);
4134 auto_vec
<ce_s
> tmpc
;
4135 get_constraint_for_address_of (gimple_call_lhs (stmt
), &tmpc
);
4136 make_constraints_to (uses
->id
, tmpc
);
4142 varinfo_t uses
= get_call_use_vi (stmt
);
4143 make_any_offset_constraints (uses
);
4144 make_transitive_closure_constraints (uses
);
4145 rhsc
.var
= uses
->id
;
4148 results
->safe_push (rhsc
);
4151 /* May return offsetted arguments. */
4152 varinfo_t tem
= NULL
;
4153 if (gimple_call_num_args (stmt
) != 0)
4155 tem
= new_var_info (NULL_TREE
, "callarg", true);
4156 tem
->is_reg_var
= true;
4158 for (k
= 0; k
< gimple_call_num_args (stmt
); ++k
)
4160 tree arg
= gimple_call_arg (stmt
, k
);
4161 auto_vec
<ce_s
> argc
;
4162 get_constraint_for_rhs (arg
, &argc
);
4163 make_constraints_to (tem
->id
, argc
);
4170 ce
.offset
= UNKNOWN_OFFSET
;
4171 results
->safe_push (ce
);
4174 /* May return addresses of globals. */
4175 rhsc
.var
= nonlocal_id
;
4177 rhsc
.type
= ADDRESSOF
;
4178 results
->safe_push (rhsc
);
4181 /* For non-IPA mode, generate constraints necessary for a call to a
4182 pure function in statement STMT. */
4185 handle_pure_call (gcall
*stmt
, vec
<ce_s
> *results
)
4187 struct constraint_expr rhsc
;
4189 varinfo_t uses
= NULL
;
4191 /* Memory reached from pointer arguments is call-used. */
4192 for (i
= 0; i
< gimple_call_num_args (stmt
); ++i
)
4194 tree arg
= gimple_call_arg (stmt
, i
);
4197 uses
= get_call_use_vi (stmt
);
4198 make_any_offset_constraints (uses
);
4199 make_transitive_closure_constraints (uses
);
4201 make_constraint_to (uses
->id
, arg
);
4204 /* The static chain is used as well. */
4205 if (gimple_call_chain (stmt
))
4209 uses
= get_call_use_vi (stmt
);
4210 make_any_offset_constraints (uses
);
4211 make_transitive_closure_constraints (uses
);
4213 make_constraint_to (uses
->id
, gimple_call_chain (stmt
));
4216 /* And if we applied NRV the address of the return slot. */
4217 if (gimple_call_return_slot_opt_p (stmt
)
4218 && gimple_call_lhs (stmt
) != NULL_TREE
4219 && TREE_ADDRESSABLE (TREE_TYPE (gimple_call_lhs (stmt
))))
4223 uses
= get_call_use_vi (stmt
);
4224 make_any_offset_constraints (uses
);
4225 make_transitive_closure_constraints (uses
);
4227 auto_vec
<ce_s
> tmpc
;
4228 get_constraint_for_address_of (gimple_call_lhs (stmt
), &tmpc
);
4229 make_constraints_to (uses
->id
, tmpc
);
4232 /* Pure functions may return call-used and nonlocal memory. */
4235 rhsc
.var
= uses
->id
;
4238 results
->safe_push (rhsc
);
4240 rhsc
.var
= nonlocal_id
;
4243 results
->safe_push (rhsc
);
4247 /* Return the varinfo for the callee of CALL. */
4250 get_fi_for_callee (gcall
*call
)
4252 tree decl
, fn
= gimple_call_fn (call
);
4254 if (fn
&& TREE_CODE (fn
) == OBJ_TYPE_REF
)
4255 fn
= OBJ_TYPE_REF_EXPR (fn
);
4257 /* If we can directly resolve the function being called, do so.
4258 Otherwise, it must be some sort of indirect expression that
4259 we should still be able to handle. */
4260 decl
= gimple_call_addr_fndecl (fn
);
4262 return get_vi_for_tree (decl
);
4264 /* If the function is anything other than a SSA name pointer we have no
4265 clue and should be getting ANYFN (well, ANYTHING for now). */
4266 if (!fn
|| TREE_CODE (fn
) != SSA_NAME
)
4267 return get_varinfo (anything_id
);
4269 if (SSA_NAME_IS_DEFAULT_DEF (fn
)
4270 && (TREE_CODE (SSA_NAME_VAR (fn
)) == PARM_DECL
4271 || TREE_CODE (SSA_NAME_VAR (fn
)) == RESULT_DECL
))
4272 fn
= SSA_NAME_VAR (fn
);
4274 return get_vi_for_tree (fn
);
4277 /* Create constraints for assigning call argument ARG to the incoming parameter
4278 INDEX of function FI. */
4281 find_func_aliases_for_call_arg (varinfo_t fi
, unsigned index
, tree arg
)
4283 struct constraint_expr lhs
;
4284 lhs
= get_function_part_constraint (fi
, fi_parm_base
+ index
);
4286 auto_vec
<ce_s
, 2> rhsc
;
4287 get_constraint_for_rhs (arg
, &rhsc
);
4290 struct constraint_expr
*rhsp
;
4291 FOR_EACH_VEC_ELT (rhsc
, j
, rhsp
)
4292 process_constraint (new_constraint (lhs
, *rhsp
));
4295 /* Return true if FNDECL may be part of another lto partition. */
4298 fndecl_maybe_in_other_partition (tree fndecl
)
4300 cgraph_node
*fn_node
= cgraph_node::get (fndecl
);
4301 if (fn_node
== NULL
)
4304 return fn_node
->in_other_partition
;
4307 /* Create constraints for the builtin call T. Return true if the call
4308 was handled, otherwise false. */
4311 find_func_aliases_for_builtin_call (struct function
*fn
, gcall
*t
)
4313 tree fndecl
= gimple_call_fndecl (t
);
4314 auto_vec
<ce_s
, 2> lhsc
;
4315 auto_vec
<ce_s
, 4> rhsc
;
4318 if (gimple_call_builtin_p (t
, BUILT_IN_NORMAL
))
4319 /* ??? All builtins that are handled here need to be handled
4320 in the alias-oracle query functions explicitly! */
4321 switch (DECL_FUNCTION_CODE (fndecl
))
4323 /* All the following functions return a pointer to the same object
4324 as their first argument points to. The functions do not add
4325 to the ESCAPED solution. The functions make the first argument
4326 pointed to memory point to what the second argument pointed to
4327 memory points to. */
4328 case BUILT_IN_STRCPY
:
4329 case BUILT_IN_STRNCPY
:
4330 case BUILT_IN_BCOPY
:
4331 case BUILT_IN_MEMCPY
:
4332 case BUILT_IN_MEMMOVE
:
4333 case BUILT_IN_MEMPCPY
:
4334 case BUILT_IN_STPCPY
:
4335 case BUILT_IN_STPNCPY
:
4336 case BUILT_IN_STRCAT
:
4337 case BUILT_IN_STRNCAT
:
4338 case BUILT_IN_STRCPY_CHK
:
4339 case BUILT_IN_STRNCPY_CHK
:
4340 case BUILT_IN_MEMCPY_CHK
:
4341 case BUILT_IN_MEMMOVE_CHK
:
4342 case BUILT_IN_MEMPCPY_CHK
:
4343 case BUILT_IN_STPCPY_CHK
:
4344 case BUILT_IN_STPNCPY_CHK
:
4345 case BUILT_IN_STRCAT_CHK
:
4346 case BUILT_IN_STRNCAT_CHK
:
4347 case BUILT_IN_TM_MEMCPY
:
4348 case BUILT_IN_TM_MEMMOVE
:
4350 tree res
= gimple_call_lhs (t
);
4351 tree dest
= gimple_call_arg (t
, (DECL_FUNCTION_CODE (fndecl
)
4352 == BUILT_IN_BCOPY
? 1 : 0));
4353 tree src
= gimple_call_arg (t
, (DECL_FUNCTION_CODE (fndecl
)
4354 == BUILT_IN_BCOPY
? 0 : 1));
4355 if (res
!= NULL_TREE
)
4357 get_constraint_for (res
, &lhsc
);
4358 if (DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_MEMPCPY
4359 || DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_STPCPY
4360 || DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_STPNCPY
4361 || DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_MEMPCPY_CHK
4362 || DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_STPCPY_CHK
4363 || DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_STPNCPY_CHK
)
4364 get_constraint_for_ptr_offset (dest
, NULL_TREE
, &rhsc
);
4366 get_constraint_for (dest
, &rhsc
);
4367 process_all_all_constraints (lhsc
, rhsc
);
4371 get_constraint_for_ptr_offset (dest
, NULL_TREE
, &lhsc
);
4372 get_constraint_for_ptr_offset (src
, NULL_TREE
, &rhsc
);
4375 process_all_all_constraints (lhsc
, rhsc
);
4378 case BUILT_IN_MEMSET
:
4379 case BUILT_IN_MEMSET_CHK
:
4380 case BUILT_IN_TM_MEMSET
:
4382 tree res
= gimple_call_lhs (t
);
4383 tree dest
= gimple_call_arg (t
, 0);
4386 struct constraint_expr ac
;
4387 if (res
!= NULL_TREE
)
4389 get_constraint_for (res
, &lhsc
);
4390 get_constraint_for (dest
, &rhsc
);
4391 process_all_all_constraints (lhsc
, rhsc
);
4394 get_constraint_for_ptr_offset (dest
, NULL_TREE
, &lhsc
);
4396 if (flag_delete_null_pointer_checks
4397 && integer_zerop (gimple_call_arg (t
, 1)))
4399 ac
.type
= ADDRESSOF
;
4400 ac
.var
= nothing_id
;
4405 ac
.var
= integer_id
;
4408 FOR_EACH_VEC_ELT (lhsc
, i
, lhsp
)
4409 process_constraint (new_constraint (*lhsp
, ac
));
4412 case BUILT_IN_STACK_SAVE
:
4413 case BUILT_IN_STACK_RESTORE
:
4414 /* Nothing interesting happens. */
4416 case BUILT_IN_ALLOCA
:
4417 case BUILT_IN_ALLOCA_WITH_ALIGN
:
4418 case BUILT_IN_ALLOCA_WITH_ALIGN_AND_MAX
:
4420 tree ptr
= gimple_call_lhs (t
);
4421 if (ptr
== NULL_TREE
)
4423 get_constraint_for (ptr
, &lhsc
);
4424 varinfo_t vi
= make_heapvar ("HEAP", true);
4425 /* Alloca storage is never global. To exempt it from escaped
4426 handling make it a non-heap var. */
4427 DECL_EXTERNAL (vi
->decl
) = 0;
4428 vi
->is_global_var
= 0;
4429 vi
->is_heap_var
= 0;
4430 struct constraint_expr tmpc
;
4433 tmpc
.type
= ADDRESSOF
;
4434 rhsc
.safe_push (tmpc
);
4435 process_all_all_constraints (lhsc
, rhsc
);
4438 case BUILT_IN_POSIX_MEMALIGN
:
4440 tree ptrptr
= gimple_call_arg (t
, 0);
4441 get_constraint_for (ptrptr
, &lhsc
);
4443 varinfo_t vi
= make_heapvar ("HEAP", true);
4444 /* We are marking allocated storage local, we deal with it becoming
4445 global by escaping and setting of vars_contains_escaped_heap. */
4446 DECL_EXTERNAL (vi
->decl
) = 0;
4447 vi
->is_global_var
= 0;
4448 struct constraint_expr tmpc
;
4451 tmpc
.type
= ADDRESSOF
;
4452 rhsc
.safe_push (tmpc
);
4453 process_all_all_constraints (lhsc
, rhsc
);
4456 case BUILT_IN_ASSUME_ALIGNED
:
4458 tree res
= gimple_call_lhs (t
);
4459 tree dest
= gimple_call_arg (t
, 0);
4460 if (res
!= NULL_TREE
)
4462 get_constraint_for (res
, &lhsc
);
4463 get_constraint_for (dest
, &rhsc
);
4464 process_all_all_constraints (lhsc
, rhsc
);
4468 /* All the following functions do not return pointers, do not
4469 modify the points-to sets of memory reachable from their
4470 arguments and do not add to the ESCAPED solution. */
4471 case BUILT_IN_SINCOS
:
4472 case BUILT_IN_SINCOSF
:
4473 case BUILT_IN_SINCOSL
:
4474 case BUILT_IN_FREXP
:
4475 case BUILT_IN_FREXPF
:
4476 case BUILT_IN_FREXPL
:
4477 case BUILT_IN_GAMMA_R
:
4478 case BUILT_IN_GAMMAF_R
:
4479 case BUILT_IN_GAMMAL_R
:
4480 case BUILT_IN_LGAMMA_R
:
4481 case BUILT_IN_LGAMMAF_R
:
4482 case BUILT_IN_LGAMMAL_R
:
4484 case BUILT_IN_MODFF
:
4485 case BUILT_IN_MODFL
:
4486 case BUILT_IN_REMQUO
:
4487 case BUILT_IN_REMQUOF
:
4488 case BUILT_IN_REMQUOL
:
4491 case BUILT_IN_STRDUP
:
4492 case BUILT_IN_STRNDUP
:
4493 case BUILT_IN_REALLOC
:
4494 if (gimple_call_lhs (t
))
4496 handle_lhs_call (t
, gimple_call_lhs (t
),
4497 gimple_call_return_flags (t
) | ERF_NOALIAS
,
4499 get_constraint_for_ptr_offset (gimple_call_lhs (t
),
4501 get_constraint_for_ptr_offset (gimple_call_arg (t
, 0),
4505 process_all_all_constraints (lhsc
, rhsc
);
4508 /* For realloc the resulting pointer can be equal to the
4509 argument as well. But only doing this wouldn't be
4510 correct because with ptr == 0 realloc behaves like malloc. */
4511 if (DECL_FUNCTION_CODE (fndecl
) == BUILT_IN_REALLOC
)
4513 get_constraint_for (gimple_call_lhs (t
), &lhsc
);
4514 get_constraint_for (gimple_call_arg (t
, 0), &rhsc
);
4515 process_all_all_constraints (lhsc
, rhsc
);
4520 /* String / character search functions return a pointer into the
4521 source string or NULL. */
4522 case BUILT_IN_INDEX
:
4523 case BUILT_IN_STRCHR
:
4524 case BUILT_IN_STRRCHR
:
4525 case BUILT_IN_MEMCHR
:
4526 case BUILT_IN_STRSTR
:
4527 case BUILT_IN_STRPBRK
:
4528 if (gimple_call_lhs (t
))
4530 tree src
= gimple_call_arg (t
, 0);
4531 get_constraint_for_ptr_offset (src
, NULL_TREE
, &rhsc
);
4532 constraint_expr nul
;
4533 nul
.var
= nothing_id
;
4535 nul
.type
= ADDRESSOF
;
4536 rhsc
.safe_push (nul
);
4537 get_constraint_for (gimple_call_lhs (t
), &lhsc
);
4538 process_all_all_constraints (lhsc
, rhsc
);
4541 /* Pure functions that return something not based on any object and
4542 that use the memory pointed to by their arguments (but not
4544 case BUILT_IN_STRCMP
:
4545 case BUILT_IN_STRCMP_EQ
:
4546 case BUILT_IN_STRNCMP
:
4547 case BUILT_IN_STRNCMP_EQ
:
4548 case BUILT_IN_STRCASECMP
:
4549 case BUILT_IN_STRNCASECMP
:
4550 case BUILT_IN_MEMCMP
:
4552 case BUILT_IN_STRSPN
:
4553 case BUILT_IN_STRCSPN
:
4555 varinfo_t uses
= get_call_use_vi (t
);
4556 make_any_offset_constraints (uses
);
4557 make_constraint_to (uses
->id
, gimple_call_arg (t
, 0));
4558 make_constraint_to (uses
->id
, gimple_call_arg (t
, 1));
4559 /* No constraints are necessary for the return value. */
4562 case BUILT_IN_STRLEN
:
4564 varinfo_t uses
= get_call_use_vi (t
);
4565 make_any_offset_constraints (uses
);
4566 make_constraint_to (uses
->id
, gimple_call_arg (t
, 0));
4567 /* No constraints are necessary for the return value. */
4570 case BUILT_IN_OBJECT_SIZE
:
4571 case BUILT_IN_CONSTANT_P
:
4573 /* No constraints are necessary for the return value or the
4577 /* Trampolines are special - they set up passing the static
4579 case BUILT_IN_INIT_TRAMPOLINE
:
4581 tree tramp
= gimple_call_arg (t
, 0);
4582 tree nfunc
= gimple_call_arg (t
, 1);
4583 tree frame
= gimple_call_arg (t
, 2);
4585 struct constraint_expr lhs
, *rhsp
;
4588 varinfo_t nfi
= NULL
;
4589 gcc_assert (TREE_CODE (nfunc
) == ADDR_EXPR
);
4590 nfi
= lookup_vi_for_tree (TREE_OPERAND (nfunc
, 0));
4593 lhs
= get_function_part_constraint (nfi
, fi_static_chain
);
4594 get_constraint_for (frame
, &rhsc
);
4595 FOR_EACH_VEC_ELT (rhsc
, i
, rhsp
)
4596 process_constraint (new_constraint (lhs
, *rhsp
));
4599 /* Make the frame point to the function for
4600 the trampoline adjustment call. */
4601 get_constraint_for (tramp
, &lhsc
);
4603 get_constraint_for (nfunc
, &rhsc
);
4604 process_all_all_constraints (lhsc
, rhsc
);
4609 /* Else fallthru to generic handling which will let
4610 the frame escape. */
4613 case BUILT_IN_ADJUST_TRAMPOLINE
:
4615 tree tramp
= gimple_call_arg (t
, 0);
4616 tree res
= gimple_call_lhs (t
);
4617 if (in_ipa_mode
&& res
)
4619 get_constraint_for (res
, &lhsc
);
4620 get_constraint_for (tramp
, &rhsc
);
4622 process_all_all_constraints (lhsc
, rhsc
);
4626 CASE_BUILT_IN_TM_STORE (1):
4627 CASE_BUILT_IN_TM_STORE (2):
4628 CASE_BUILT_IN_TM_STORE (4):
4629 CASE_BUILT_IN_TM_STORE (8):
4630 CASE_BUILT_IN_TM_STORE (FLOAT
):
4631 CASE_BUILT_IN_TM_STORE (DOUBLE
):
4632 CASE_BUILT_IN_TM_STORE (LDOUBLE
):
4633 CASE_BUILT_IN_TM_STORE (M64
):
4634 CASE_BUILT_IN_TM_STORE (M128
):
4635 CASE_BUILT_IN_TM_STORE (M256
):
4637 tree addr
= gimple_call_arg (t
, 0);
4638 tree src
= gimple_call_arg (t
, 1);
4640 get_constraint_for (addr
, &lhsc
);
4642 get_constraint_for (src
, &rhsc
);
4643 process_all_all_constraints (lhsc
, rhsc
);
4646 CASE_BUILT_IN_TM_LOAD (1):
4647 CASE_BUILT_IN_TM_LOAD (2):
4648 CASE_BUILT_IN_TM_LOAD (4):
4649 CASE_BUILT_IN_TM_LOAD (8):
4650 CASE_BUILT_IN_TM_LOAD (FLOAT
):
4651 CASE_BUILT_IN_TM_LOAD (DOUBLE
):
4652 CASE_BUILT_IN_TM_LOAD (LDOUBLE
):
4653 CASE_BUILT_IN_TM_LOAD (M64
):
4654 CASE_BUILT_IN_TM_LOAD (M128
):
4655 CASE_BUILT_IN_TM_LOAD (M256
):
4657 tree dest
= gimple_call_lhs (t
);
4658 tree addr
= gimple_call_arg (t
, 0);
4660 get_constraint_for (dest
, &lhsc
);
4661 get_constraint_for (addr
, &rhsc
);
4663 process_all_all_constraints (lhsc
, rhsc
);
4666 /* Variadic argument handling needs to be handled in IPA
4668 case BUILT_IN_VA_START
:
4670 tree valist
= gimple_call_arg (t
, 0);
4671 struct constraint_expr rhs
, *lhsp
;
4673 get_constraint_for_ptr_offset (valist
, NULL_TREE
, &lhsc
);
4675 /* The va_list gets access to pointers in variadic
4676 arguments. Which we know in the case of IPA analysis
4677 and otherwise are just all nonlocal variables. */
4680 fi
= lookup_vi_for_tree (fn
->decl
);
4681 rhs
= get_function_part_constraint (fi
, ~0);
4682 rhs
.type
= ADDRESSOF
;
4686 rhs
.var
= nonlocal_id
;
4687 rhs
.type
= ADDRESSOF
;
4690 FOR_EACH_VEC_ELT (lhsc
, i
, lhsp
)
4691 process_constraint (new_constraint (*lhsp
, rhs
));
4692 /* va_list is clobbered. */
4693 make_constraint_to (get_call_clobber_vi (t
)->id
, valist
);
4696 /* va_end doesn't have any effect that matters. */
4697 case BUILT_IN_VA_END
:
4699 /* Alternate return. Simply give up for now. */
4700 case BUILT_IN_RETURN
:
4704 || !(fi
= get_vi_for_tree (fn
->decl
)))
4705 make_constraint_from (get_varinfo (escaped_id
), anything_id
);
4706 else if (in_ipa_mode
4709 struct constraint_expr lhs
, rhs
;
4710 lhs
= get_function_part_constraint (fi
, fi_result
);
4711 rhs
.var
= anything_id
;
4714 process_constraint (new_constraint (lhs
, rhs
));
4718 case BUILT_IN_GOMP_PARALLEL
:
4719 case BUILT_IN_GOACC_PARALLEL
:
4723 unsigned int fnpos
, argpos
;
4724 switch (DECL_FUNCTION_CODE (fndecl
))
4726 case BUILT_IN_GOMP_PARALLEL
:
4727 /* __builtin_GOMP_parallel (fn, data, num_threads, flags). */
4731 case BUILT_IN_GOACC_PARALLEL
:
4732 /* __builtin_GOACC_parallel (flags_m, fn, mapnum, hostaddrs,
4733 sizes, kinds, ...). */
4741 tree fnarg
= gimple_call_arg (t
, fnpos
);
4742 gcc_assert (TREE_CODE (fnarg
) == ADDR_EXPR
);
4743 tree fndecl
= TREE_OPERAND (fnarg
, 0);
4744 if (fndecl_maybe_in_other_partition (fndecl
))
4745 /* Fallthru to general call handling. */
4748 tree arg
= gimple_call_arg (t
, argpos
);
4750 varinfo_t fi
= get_vi_for_tree (fndecl
);
4751 find_func_aliases_for_call_arg (fi
, 0, arg
);
4754 /* Else fallthru to generic call handling. */
4757 /* printf-style functions may have hooks to set pointers to
4758 point to somewhere into the generated string. Leave them
4759 for a later exercise... */
4761 /* Fallthru to general call handling. */;
4767 /* Create constraints for the call T. */
4770 find_func_aliases_for_call (struct function
*fn
, gcall
*t
)
4772 tree fndecl
= gimple_call_fndecl (t
);
4775 if (fndecl
!= NULL_TREE
4776 && fndecl_built_in_p (fndecl
)
4777 && find_func_aliases_for_builtin_call (fn
, t
))
4780 fi
= get_fi_for_callee (t
);
4782 || (fi
->decl
&& fndecl
&& !fi
->is_fn_info
))
4784 auto_vec
<ce_s
, 16> rhsc
;
4785 int flags
= gimple_call_flags (t
);
4787 /* Const functions can return their arguments and addresses
4788 of global memory but not of escaped memory. */
4789 if (flags
& (ECF_CONST
|ECF_NOVOPS
))
4791 if (gimple_call_lhs (t
))
4792 handle_const_call (t
, &rhsc
);
4794 /* Pure functions can return addresses in and of memory
4795 reachable from their arguments, but they are not an escape
4796 point for reachable memory of their arguments. */
4797 else if (flags
& (ECF_PURE
|ECF_LOOPING_CONST_OR_PURE
))
4798 handle_pure_call (t
, &rhsc
);
4800 handle_rhs_call (t
, &rhsc
);
4801 if (gimple_call_lhs (t
))
4802 handle_lhs_call (t
, gimple_call_lhs (t
),
4803 gimple_call_return_flags (t
), rhsc
, fndecl
);
4807 auto_vec
<ce_s
, 2> rhsc
;
4811 /* Assign all the passed arguments to the appropriate incoming
4812 parameters of the function. */
4813 for (j
= 0; j
< gimple_call_num_args (t
); j
++)
4815 tree arg
= gimple_call_arg (t
, j
);
4816 find_func_aliases_for_call_arg (fi
, j
, arg
);
4819 /* If we are returning a value, assign it to the result. */
4820 lhsop
= gimple_call_lhs (t
);
4823 auto_vec
<ce_s
, 2> lhsc
;
4824 struct constraint_expr rhs
;
4825 struct constraint_expr
*lhsp
;
4826 bool aggr_p
= aggregate_value_p (lhsop
, gimple_call_fntype (t
));
4828 get_constraint_for (lhsop
, &lhsc
);
4829 rhs
= get_function_part_constraint (fi
, fi_result
);
4832 auto_vec
<ce_s
, 2> tem
;
4833 tem
.quick_push (rhs
);
4835 gcc_checking_assert (tem
.length () == 1);
4838 FOR_EACH_VEC_ELT (lhsc
, j
, lhsp
)
4839 process_constraint (new_constraint (*lhsp
, rhs
));
4841 /* If we pass the result decl by reference, honor that. */
4844 struct constraint_expr lhs
;
4845 struct constraint_expr
*rhsp
;
4847 get_constraint_for_address_of (lhsop
, &rhsc
);
4848 lhs
= get_function_part_constraint (fi
, fi_result
);
4849 FOR_EACH_VEC_ELT (rhsc
, j
, rhsp
)
4850 process_constraint (new_constraint (lhs
, *rhsp
));
4855 /* If we use a static chain, pass it along. */
4856 if (gimple_call_chain (t
))
4858 struct constraint_expr lhs
;
4859 struct constraint_expr
*rhsp
;
4861 get_constraint_for (gimple_call_chain (t
), &rhsc
);
4862 lhs
= get_function_part_constraint (fi
, fi_static_chain
);
4863 FOR_EACH_VEC_ELT (rhsc
, j
, rhsp
)
4864 process_constraint (new_constraint (lhs
, *rhsp
));
4869 /* Walk statement T setting up aliasing constraints according to the
4870 references found in T. This function is the main part of the
4871 constraint builder. AI points to auxiliary alias information used
4872 when building alias sets and computing alias grouping heuristics. */
4875 find_func_aliases (struct function
*fn
, gimple
*origt
)
4878 auto_vec
<ce_s
, 16> lhsc
;
4879 auto_vec
<ce_s
, 16> rhsc
;
4882 /* Now build constraints expressions. */
4883 if (gimple_code (t
) == GIMPLE_PHI
)
4885 /* For a phi node, assign all the arguments to
4887 get_constraint_for (gimple_phi_result (t
), &lhsc
);
4888 for (unsigned i
= 0; i
< gimple_phi_num_args (t
); i
++)
4890 get_constraint_for_rhs (gimple_phi_arg_def (t
, i
), &rhsc
);
4891 process_all_all_constraints (lhsc
, rhsc
);
4895 /* In IPA mode, we need to generate constraints to pass call
4896 arguments through their calls. There are two cases,
4897 either a GIMPLE_CALL returning a value, or just a plain
4898 GIMPLE_CALL when we are not.
4900 In non-ipa mode, we need to generate constraints for each
4901 pointer passed by address. */
4902 else if (is_gimple_call (t
))
4903 find_func_aliases_for_call (fn
, as_a
<gcall
*> (t
));
4905 /* Otherwise, just a regular assignment statement. Only care about
4906 operations with pointer result, others are dealt with as escape
4907 points if they have pointer operands. */
4908 else if (is_gimple_assign (t
))
4910 /* Otherwise, just a regular assignment statement. */
4911 tree lhsop
= gimple_assign_lhs (t
);
4912 tree rhsop
= (gimple_num_ops (t
) == 2) ? gimple_assign_rhs1 (t
) : NULL
;
4914 if (rhsop
&& TREE_CLOBBER_P (rhsop
))
4915 /* Ignore clobbers, they don't actually store anything into
4918 else if (rhsop
&& AGGREGATE_TYPE_P (TREE_TYPE (lhsop
)))
4919 do_structure_copy (lhsop
, rhsop
);
4922 enum tree_code code
= gimple_assign_rhs_code (t
);
4924 get_constraint_for (lhsop
, &lhsc
);
4926 if (code
== POINTER_PLUS_EXPR
)
4927 get_constraint_for_ptr_offset (gimple_assign_rhs1 (t
),
4928 gimple_assign_rhs2 (t
), &rhsc
);
4929 else if (code
== POINTER_DIFF_EXPR
)
4930 /* The result is not a pointer (part). */
4932 else if (code
== BIT_AND_EXPR
4933 && TREE_CODE (gimple_assign_rhs2 (t
)) == INTEGER_CST
)
4935 /* Aligning a pointer via a BIT_AND_EXPR is offsetting
4936 the pointer. Handle it by offsetting it by UNKNOWN. */
4937 get_constraint_for_ptr_offset (gimple_assign_rhs1 (t
),
4940 else if (code
== TRUNC_DIV_EXPR
4941 || code
== CEIL_DIV_EXPR
4942 || code
== FLOOR_DIV_EXPR
4943 || code
== ROUND_DIV_EXPR
4944 || code
== EXACT_DIV_EXPR
4945 || code
== TRUNC_MOD_EXPR
4946 || code
== CEIL_MOD_EXPR
4947 || code
== FLOOR_MOD_EXPR
4948 || code
== ROUND_MOD_EXPR
)
4949 /* Division and modulo transfer the pointer from the LHS. */
4950 get_constraint_for_rhs (gimple_assign_rhs1 (t
), &rhsc
);
4951 else if ((CONVERT_EXPR_CODE_P (code
)
4952 && !(POINTER_TYPE_P (gimple_expr_type (t
))
4953 && !POINTER_TYPE_P (TREE_TYPE (rhsop
))))
4954 || gimple_assign_single_p (t
))
4955 get_constraint_for_rhs (rhsop
, &rhsc
);
4956 else if (code
== COND_EXPR
)
4958 /* The result is a merge of both COND_EXPR arms. */
4959 auto_vec
<ce_s
, 2> tmp
;
4960 struct constraint_expr
*rhsp
;
4962 get_constraint_for_rhs (gimple_assign_rhs2 (t
), &rhsc
);
4963 get_constraint_for_rhs (gimple_assign_rhs3 (t
), &tmp
);
4964 FOR_EACH_VEC_ELT (tmp
, i
, rhsp
)
4965 rhsc
.safe_push (*rhsp
);
4967 else if (truth_value_p (code
))
4968 /* Truth value results are not pointer (parts). Or at least
4969 very unreasonable obfuscation of a part. */
4973 /* All other operations are merges. */
4974 auto_vec
<ce_s
, 4> tmp
;
4975 struct constraint_expr
*rhsp
;
4977 get_constraint_for_rhs (gimple_assign_rhs1 (t
), &rhsc
);
4978 for (i
= 2; i
< gimple_num_ops (t
); ++i
)
4980 get_constraint_for_rhs (gimple_op (t
, i
), &tmp
);
4981 FOR_EACH_VEC_ELT (tmp
, j
, rhsp
)
4982 rhsc
.safe_push (*rhsp
);
4986 process_all_all_constraints (lhsc
, rhsc
);
4988 /* If there is a store to a global variable the rhs escapes. */
4989 if ((lhsop
= get_base_address (lhsop
)) != NULL_TREE
4992 varinfo_t vi
= get_vi_for_tree (lhsop
);
4993 if ((! in_ipa_mode
&& vi
->is_global_var
)
4994 || vi
->is_ipa_escape_point
)
4995 make_escape_constraint (rhsop
);
4998 /* Handle escapes through return. */
4999 else if (gimple_code (t
) == GIMPLE_RETURN
5000 && gimple_return_retval (as_a
<greturn
*> (t
)) != NULL_TREE
)
5002 greturn
*return_stmt
= as_a
<greturn
*> (t
);
5005 && SSA_VAR_P (gimple_return_retval (return_stmt
)))
5007 /* We handle simple returns by post-processing the solutions. */
5010 if (!(fi
= get_vi_for_tree (fn
->decl
)))
5011 make_escape_constraint (gimple_return_retval (return_stmt
));
5012 else if (in_ipa_mode
)
5014 struct constraint_expr lhs
;
5015 struct constraint_expr
*rhsp
;
5018 lhs
= get_function_part_constraint (fi
, fi_result
);
5019 get_constraint_for_rhs (gimple_return_retval (return_stmt
), &rhsc
);
5020 FOR_EACH_VEC_ELT (rhsc
, i
, rhsp
)
5021 process_constraint (new_constraint (lhs
, *rhsp
));
5024 /* Handle asms conservatively by adding escape constraints to everything. */
5025 else if (gasm
*asm_stmt
= dyn_cast
<gasm
*> (t
))
5027 unsigned i
, noutputs
;
5028 const char **oconstraints
;
5029 const char *constraint
;
5030 bool allows_mem
, allows_reg
, is_inout
;
5032 noutputs
= gimple_asm_noutputs (asm_stmt
);
5033 oconstraints
= XALLOCAVEC (const char *, noutputs
);
5035 for (i
= 0; i
< noutputs
; ++i
)
5037 tree link
= gimple_asm_output_op (asm_stmt
, i
);
5038 tree op
= TREE_VALUE (link
);
5040 constraint
= TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link
)));
5041 oconstraints
[i
] = constraint
;
5042 parse_output_constraint (&constraint
, i
, 0, 0, &allows_mem
,
5043 &allows_reg
, &is_inout
);
5045 /* A memory constraint makes the address of the operand escape. */
5046 if (!allows_reg
&& allows_mem
)
5047 make_escape_constraint (build_fold_addr_expr (op
));
5049 /* The asm may read global memory, so outputs may point to
5050 any global memory. */
5053 auto_vec
<ce_s
, 2> lhsc
;
5054 struct constraint_expr rhsc
, *lhsp
;
5056 get_constraint_for (op
, &lhsc
);
5057 rhsc
.var
= nonlocal_id
;
5060 FOR_EACH_VEC_ELT (lhsc
, j
, lhsp
)
5061 process_constraint (new_constraint (*lhsp
, rhsc
));
5064 for (i
= 0; i
< gimple_asm_ninputs (asm_stmt
); ++i
)
5066 tree link
= gimple_asm_input_op (asm_stmt
, i
);
5067 tree op
= TREE_VALUE (link
);
5069 constraint
= TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link
)));
5071 parse_input_constraint (&constraint
, 0, 0, noutputs
, 0, oconstraints
,
5072 &allows_mem
, &allows_reg
);
5074 /* A memory constraint makes the address of the operand escape. */
5075 if (!allows_reg
&& allows_mem
)
5076 make_escape_constraint (build_fold_addr_expr (op
));
5077 /* Strictly we'd only need the constraint to ESCAPED if
5078 the asm clobbers memory, otherwise using something
5079 along the lines of per-call clobbers/uses would be enough. */
5081 make_escape_constraint (op
);
5087 /* Create a constraint adding to the clobber set of FI the memory
5088 pointed to by PTR. */
5091 process_ipa_clobber (varinfo_t fi
, tree ptr
)
5093 vec
<ce_s
> ptrc
= vNULL
;
5094 struct constraint_expr
*c
, lhs
;
5096 get_constraint_for_rhs (ptr
, &ptrc
);
5097 lhs
= get_function_part_constraint (fi
, fi_clobbers
);
5098 FOR_EACH_VEC_ELT (ptrc
, i
, c
)
5099 process_constraint (new_constraint (lhs
, *c
));
5103 /* Walk statement T setting up clobber and use constraints according to the
5104 references found in T. This function is a main part of the
5105 IPA constraint builder. */
5108 find_func_clobbers (struct function
*fn
, gimple
*origt
)
5111 auto_vec
<ce_s
, 16> lhsc
;
5112 auto_vec
<ce_s
, 16> rhsc
;
5115 /* Add constraints for clobbered/used in IPA mode.
5116 We are not interested in what automatic variables are clobbered
5117 or used as we only use the information in the caller to which
5118 they do not escape. */
5119 gcc_assert (in_ipa_mode
);
5121 /* If the stmt refers to memory in any way it better had a VUSE. */
5122 if (gimple_vuse (t
) == NULL_TREE
)
5125 /* We'd better have function information for the current function. */
5126 fi
= lookup_vi_for_tree (fn
->decl
);
5127 gcc_assert (fi
!= NULL
);
5129 /* Account for stores in assignments and calls. */
5130 if (gimple_vdef (t
) != NULL_TREE
5131 && gimple_has_lhs (t
))
5133 tree lhs
= gimple_get_lhs (t
);
5135 while (handled_component_p (tem
))
5136 tem
= TREE_OPERAND (tem
, 0);
5138 && !auto_var_in_fn_p (tem
, fn
->decl
))
5139 || INDIRECT_REF_P (tem
)
5140 || (TREE_CODE (tem
) == MEM_REF
5141 && !(TREE_CODE (TREE_OPERAND (tem
, 0)) == ADDR_EXPR
5143 (TREE_OPERAND (TREE_OPERAND (tem
, 0), 0), fn
->decl
))))
5145 struct constraint_expr lhsc
, *rhsp
;
5147 lhsc
= get_function_part_constraint (fi
, fi_clobbers
);
5148 get_constraint_for_address_of (lhs
, &rhsc
);
5149 FOR_EACH_VEC_ELT (rhsc
, i
, rhsp
)
5150 process_constraint (new_constraint (lhsc
, *rhsp
));
5155 /* Account for uses in assigments and returns. */
5156 if (gimple_assign_single_p (t
)
5157 || (gimple_code (t
) == GIMPLE_RETURN
5158 && gimple_return_retval (as_a
<greturn
*> (t
)) != NULL_TREE
))
5160 tree rhs
= (gimple_assign_single_p (t
)
5161 ? gimple_assign_rhs1 (t
)
5162 : gimple_return_retval (as_a
<greturn
*> (t
)));
5164 while (handled_component_p (tem
))
5165 tem
= TREE_OPERAND (tem
, 0);
5167 && !auto_var_in_fn_p (tem
, fn
->decl
))
5168 || INDIRECT_REF_P (tem
)
5169 || (TREE_CODE (tem
) == MEM_REF
5170 && !(TREE_CODE (TREE_OPERAND (tem
, 0)) == ADDR_EXPR
5172 (TREE_OPERAND (TREE_OPERAND (tem
, 0), 0), fn
->decl
))))
5174 struct constraint_expr lhs
, *rhsp
;
5176 lhs
= get_function_part_constraint (fi
, fi_uses
);
5177 get_constraint_for_address_of (rhs
, &rhsc
);
5178 FOR_EACH_VEC_ELT (rhsc
, i
, rhsp
)
5179 process_constraint (new_constraint (lhs
, *rhsp
));
5184 if (gcall
*call_stmt
= dyn_cast
<gcall
*> (t
))
5186 varinfo_t cfi
= NULL
;
5187 tree decl
= gimple_call_fndecl (t
);
5188 struct constraint_expr lhs
, rhs
;
5191 /* For builtins we do not have separate function info. For those
5192 we do not generate escapes for we have to generate clobbers/uses. */
5193 if (gimple_call_builtin_p (t
, BUILT_IN_NORMAL
))
5194 switch (DECL_FUNCTION_CODE (decl
))
5196 /* The following functions use and clobber memory pointed to
5197 by their arguments. */
5198 case BUILT_IN_STRCPY
:
5199 case BUILT_IN_STRNCPY
:
5200 case BUILT_IN_BCOPY
:
5201 case BUILT_IN_MEMCPY
:
5202 case BUILT_IN_MEMMOVE
:
5203 case BUILT_IN_MEMPCPY
:
5204 case BUILT_IN_STPCPY
:
5205 case BUILT_IN_STPNCPY
:
5206 case BUILT_IN_STRCAT
:
5207 case BUILT_IN_STRNCAT
:
5208 case BUILT_IN_STRCPY_CHK
:
5209 case BUILT_IN_STRNCPY_CHK
:
5210 case BUILT_IN_MEMCPY_CHK
:
5211 case BUILT_IN_MEMMOVE_CHK
:
5212 case BUILT_IN_MEMPCPY_CHK
:
5213 case BUILT_IN_STPCPY_CHK
:
5214 case BUILT_IN_STPNCPY_CHK
:
5215 case BUILT_IN_STRCAT_CHK
:
5216 case BUILT_IN_STRNCAT_CHK
:
5218 tree dest
= gimple_call_arg (t
, (DECL_FUNCTION_CODE (decl
)
5219 == BUILT_IN_BCOPY
? 1 : 0));
5220 tree src
= gimple_call_arg (t
, (DECL_FUNCTION_CODE (decl
)
5221 == BUILT_IN_BCOPY
? 0 : 1));
5223 struct constraint_expr
*rhsp
, *lhsp
;
5224 get_constraint_for_ptr_offset (dest
, NULL_TREE
, &lhsc
);
5225 lhs
= get_function_part_constraint (fi
, fi_clobbers
);
5226 FOR_EACH_VEC_ELT (lhsc
, i
, lhsp
)
5227 process_constraint (new_constraint (lhs
, *lhsp
));
5228 get_constraint_for_ptr_offset (src
, NULL_TREE
, &rhsc
);
5229 lhs
= get_function_part_constraint (fi
, fi_uses
);
5230 FOR_EACH_VEC_ELT (rhsc
, i
, rhsp
)
5231 process_constraint (new_constraint (lhs
, *rhsp
));
5234 /* The following function clobbers memory pointed to by
5236 case BUILT_IN_MEMSET
:
5237 case BUILT_IN_MEMSET_CHK
:
5238 case BUILT_IN_POSIX_MEMALIGN
:
5240 tree dest
= gimple_call_arg (t
, 0);
5243 get_constraint_for_ptr_offset (dest
, NULL_TREE
, &lhsc
);
5244 lhs
= get_function_part_constraint (fi
, fi_clobbers
);
5245 FOR_EACH_VEC_ELT (lhsc
, i
, lhsp
)
5246 process_constraint (new_constraint (lhs
, *lhsp
));
5249 /* The following functions clobber their second and third
5251 case BUILT_IN_SINCOS
:
5252 case BUILT_IN_SINCOSF
:
5253 case BUILT_IN_SINCOSL
:
5255 process_ipa_clobber (fi
, gimple_call_arg (t
, 1));
5256 process_ipa_clobber (fi
, gimple_call_arg (t
, 2));
5259 /* The following functions clobber their second argument. */
5260 case BUILT_IN_FREXP
:
5261 case BUILT_IN_FREXPF
:
5262 case BUILT_IN_FREXPL
:
5263 case BUILT_IN_LGAMMA_R
:
5264 case BUILT_IN_LGAMMAF_R
:
5265 case BUILT_IN_LGAMMAL_R
:
5266 case BUILT_IN_GAMMA_R
:
5267 case BUILT_IN_GAMMAF_R
:
5268 case BUILT_IN_GAMMAL_R
:
5270 case BUILT_IN_MODFF
:
5271 case BUILT_IN_MODFL
:
5273 process_ipa_clobber (fi
, gimple_call_arg (t
, 1));
5276 /* The following functions clobber their third argument. */
5277 case BUILT_IN_REMQUO
:
5278 case BUILT_IN_REMQUOF
:
5279 case BUILT_IN_REMQUOL
:
5281 process_ipa_clobber (fi
, gimple_call_arg (t
, 2));
5284 /* The following functions neither read nor clobber memory. */
5285 case BUILT_IN_ASSUME_ALIGNED
:
5288 /* Trampolines are of no interest to us. */
5289 case BUILT_IN_INIT_TRAMPOLINE
:
5290 case BUILT_IN_ADJUST_TRAMPOLINE
:
5292 case BUILT_IN_VA_START
:
5293 case BUILT_IN_VA_END
:
5295 case BUILT_IN_GOMP_PARALLEL
:
5296 case BUILT_IN_GOACC_PARALLEL
:
5298 unsigned int fnpos
, argpos
;
5299 unsigned int implicit_use_args
[2];
5300 unsigned int num_implicit_use_args
= 0;
5301 switch (DECL_FUNCTION_CODE (decl
))
5303 case BUILT_IN_GOMP_PARALLEL
:
5304 /* __builtin_GOMP_parallel (fn, data, num_threads, flags). */
5308 case BUILT_IN_GOACC_PARALLEL
:
5309 /* __builtin_GOACC_parallel (flags_m, fn, mapnum, hostaddrs,
5310 sizes, kinds, ...). */
5313 implicit_use_args
[num_implicit_use_args
++] = 4;
5314 implicit_use_args
[num_implicit_use_args
++] = 5;
5320 tree fnarg
= gimple_call_arg (t
, fnpos
);
5321 gcc_assert (TREE_CODE (fnarg
) == ADDR_EXPR
);
5322 tree fndecl
= TREE_OPERAND (fnarg
, 0);
5323 if (fndecl_maybe_in_other_partition (fndecl
))
5324 /* Fallthru to general call handling. */
5327 varinfo_t cfi
= get_vi_for_tree (fndecl
);
5329 tree arg
= gimple_call_arg (t
, argpos
);
5331 /* Parameter passed by value is used. */
5332 lhs
= get_function_part_constraint (fi
, fi_uses
);
5333 struct constraint_expr
*rhsp
;
5334 get_constraint_for (arg
, &rhsc
);
5335 FOR_EACH_VEC_ELT (rhsc
, j
, rhsp
)
5336 process_constraint (new_constraint (lhs
, *rhsp
));
5339 /* Handle parameters used by the call, but not used in cfi, as
5340 implicitly used by cfi. */
5341 lhs
= get_function_part_constraint (cfi
, fi_uses
);
5342 for (unsigned i
= 0; i
< num_implicit_use_args
; ++i
)
5344 tree arg
= gimple_call_arg (t
, implicit_use_args
[i
]);
5345 get_constraint_for (arg
, &rhsc
);
5346 FOR_EACH_VEC_ELT (rhsc
, j
, rhsp
)
5347 process_constraint (new_constraint (lhs
, *rhsp
));
5351 /* The caller clobbers what the callee does. */
5352 lhs
= get_function_part_constraint (fi
, fi_clobbers
);
5353 rhs
= get_function_part_constraint (cfi
, fi_clobbers
);
5354 process_constraint (new_constraint (lhs
, rhs
));
5356 /* The caller uses what the callee does. */
5357 lhs
= get_function_part_constraint (fi
, fi_uses
);
5358 rhs
= get_function_part_constraint (cfi
, fi_uses
);
5359 process_constraint (new_constraint (lhs
, rhs
));
5363 /* printf-style functions may have hooks to set pointers to
5364 point to somewhere into the generated string. Leave them
5365 for a later exercise... */
5367 /* Fallthru to general call handling. */;
5370 /* Parameters passed by value are used. */
5371 lhs
= get_function_part_constraint (fi
, fi_uses
);
5372 for (i
= 0; i
< gimple_call_num_args (t
); i
++)
5374 struct constraint_expr
*rhsp
;
5375 tree arg
= gimple_call_arg (t
, i
);
5377 if (TREE_CODE (arg
) == SSA_NAME
5378 || is_gimple_min_invariant (arg
))
5381 get_constraint_for_address_of (arg
, &rhsc
);
5382 FOR_EACH_VEC_ELT (rhsc
, j
, rhsp
)
5383 process_constraint (new_constraint (lhs
, *rhsp
));
5387 /* Build constraints for propagating clobbers/uses along the
5389 cfi
= get_fi_for_callee (call_stmt
);
5390 if (cfi
->id
== anything_id
)
5392 if (gimple_vdef (t
))
5393 make_constraint_from (first_vi_for_offset (fi
, fi_clobbers
),
5395 make_constraint_from (first_vi_for_offset (fi
, fi_uses
),
5400 /* For callees without function info (that's external functions),
5401 ESCAPED is clobbered and used. */
5403 && TREE_CODE (cfi
->decl
) == FUNCTION_DECL
5404 && !cfi
->is_fn_info
)
5408 if (gimple_vdef (t
))
5409 make_copy_constraint (first_vi_for_offset (fi
, fi_clobbers
),
5411 make_copy_constraint (first_vi_for_offset (fi
, fi_uses
), escaped_id
);
5413 /* Also honor the call statement use/clobber info. */
5414 if ((vi
= lookup_call_clobber_vi (call_stmt
)) != NULL
)
5415 make_copy_constraint (first_vi_for_offset (fi
, fi_clobbers
),
5417 if ((vi
= lookup_call_use_vi (call_stmt
)) != NULL
)
5418 make_copy_constraint (first_vi_for_offset (fi
, fi_uses
),
5423 /* Otherwise the caller clobbers and uses what the callee does.
5424 ??? This should use a new complex constraint that filters
5425 local variables of the callee. */
5426 if (gimple_vdef (t
))
5428 lhs
= get_function_part_constraint (fi
, fi_clobbers
);
5429 rhs
= get_function_part_constraint (cfi
, fi_clobbers
);
5430 process_constraint (new_constraint (lhs
, rhs
));
5432 lhs
= get_function_part_constraint (fi
, fi_uses
);
5433 rhs
= get_function_part_constraint (cfi
, fi_uses
);
5434 process_constraint (new_constraint (lhs
, rhs
));
5436 else if (gimple_code (t
) == GIMPLE_ASM
)
5438 /* ??? Ick. We can do better. */
5439 if (gimple_vdef (t
))
5440 make_constraint_from (first_vi_for_offset (fi
, fi_clobbers
),
5442 make_constraint_from (first_vi_for_offset (fi
, fi_uses
),
5448 /* Find the first varinfo in the same variable as START that overlaps with
5449 OFFSET. Return NULL if we can't find one. */
5452 first_vi_for_offset (varinfo_t start
, unsigned HOST_WIDE_INT offset
)
5454 /* If the offset is outside of the variable, bail out. */
5455 if (offset
>= start
->fullsize
)
5458 /* If we cannot reach offset from start, lookup the first field
5459 and start from there. */
5460 if (start
->offset
> offset
)
5461 start
= get_varinfo (start
->head
);
5465 /* We may not find a variable in the field list with the actual
5466 offset when we have glommed a structure to a variable.
5467 In that case, however, offset should still be within the size
5469 if (offset
>= start
->offset
5470 && (offset
- start
->offset
) < start
->size
)
5473 start
= vi_next (start
);
5479 /* Find the first varinfo in the same variable as START that overlaps with
5480 OFFSET. If there is no such varinfo the varinfo directly preceding
5481 OFFSET is returned. */
5484 first_or_preceding_vi_for_offset (varinfo_t start
,
5485 unsigned HOST_WIDE_INT offset
)
5487 /* If we cannot reach offset from start, lookup the first field
5488 and start from there. */
5489 if (start
->offset
> offset
)
5490 start
= get_varinfo (start
->head
);
5492 /* We may not find a variable in the field list with the actual
5493 offset when we have glommed a structure to a variable.
5494 In that case, however, offset should still be within the size
5496 If we got beyond the offset we look for return the field
5497 directly preceding offset which may be the last field. */
5499 && offset
>= start
->offset
5500 && !((offset
- start
->offset
) < start
->size
))
5501 start
= vi_next (start
);
5507 /* This structure is used during pushing fields onto the fieldstack
5508 to track the offset of the field, since bitpos_of_field gives it
5509 relative to its immediate containing type, and we want it relative
5510 to the ultimate containing object. */
5514 /* Offset from the base of the base containing object to this field. */
5515 HOST_WIDE_INT offset
;
5517 /* Size, in bits, of the field. */
5518 unsigned HOST_WIDE_INT size
;
5520 unsigned has_unknown_size
: 1;
5522 unsigned must_have_pointers
: 1;
5524 unsigned may_have_pointers
: 1;
5526 unsigned only_restrict_pointers
: 1;
5528 tree restrict_pointed_type
;
5530 typedef struct fieldoff fieldoff_s
;
5533 /* qsort comparison function for two fieldoff's PA and PB */
5536 fieldoff_compare (const void *pa
, const void *pb
)
5538 const fieldoff_s
*foa
= (const fieldoff_s
*)pa
;
5539 const fieldoff_s
*fob
= (const fieldoff_s
*)pb
;
5540 unsigned HOST_WIDE_INT foasize
, fobsize
;
5542 if (foa
->offset
< fob
->offset
)
5544 else if (foa
->offset
> fob
->offset
)
5547 foasize
= foa
->size
;
5548 fobsize
= fob
->size
;
5549 if (foasize
< fobsize
)
5551 else if (foasize
> fobsize
)
5556 /* Sort a fieldstack according to the field offset and sizes. */
5558 sort_fieldstack (vec
<fieldoff_s
> fieldstack
)
5560 fieldstack
.qsort (fieldoff_compare
);
5563 /* Return true if T is a type that can have subvars. */
5566 type_can_have_subvars (const_tree t
)
5568 /* Aggregates without overlapping fields can have subvars. */
5569 return TREE_CODE (t
) == RECORD_TYPE
;
5572 /* Return true if V is a tree that we can have subvars for.
5573 Normally, this is any aggregate type. Also complex
5574 types which are not gimple registers can have subvars. */
5577 var_can_have_subvars (const_tree v
)
5579 /* Volatile variables should never have subvars. */
5580 if (TREE_THIS_VOLATILE (v
))
5583 /* Non decls or memory tags can never have subvars. */
5587 return type_can_have_subvars (TREE_TYPE (v
));
5590 /* Return true if T is a type that does contain pointers. */
5593 type_must_have_pointers (tree type
)
5595 if (POINTER_TYPE_P (type
))
5598 if (TREE_CODE (type
) == ARRAY_TYPE
)
5599 return type_must_have_pointers (TREE_TYPE (type
));
5601 /* A function or method can have pointers as arguments, so track
5602 those separately. */
5603 if (TREE_CODE (type
) == FUNCTION_TYPE
5604 || TREE_CODE (type
) == METHOD_TYPE
)
5611 field_must_have_pointers (tree t
)
5613 return type_must_have_pointers (TREE_TYPE (t
));
5616 /* Given a TYPE, and a vector of field offsets FIELDSTACK, push all
5617 the fields of TYPE onto fieldstack, recording their offsets along
5620 OFFSET is used to keep track of the offset in this entire
5621 structure, rather than just the immediately containing structure.
5622 Returns false if the caller is supposed to handle the field we
5626 push_fields_onto_fieldstack (tree type
, vec
<fieldoff_s
> *fieldstack
,
5627 HOST_WIDE_INT offset
)
5630 bool empty_p
= true;
5632 if (TREE_CODE (type
) != RECORD_TYPE
)
5635 /* If the vector of fields is growing too big, bail out early.
5636 Callers check for vec::length <= MAX_FIELDS_FOR_FIELD_SENSITIVE, make
5638 if (fieldstack
->length () > MAX_FIELDS_FOR_FIELD_SENSITIVE
)
5641 for (field
= TYPE_FIELDS (type
); field
; field
= DECL_CHAIN (field
))
5642 if (TREE_CODE (field
) == FIELD_DECL
)
5645 HOST_WIDE_INT foff
= bitpos_of_field (field
);
5646 tree field_type
= TREE_TYPE (field
);
5648 if (!var_can_have_subvars (field
)
5649 || TREE_CODE (field_type
) == QUAL_UNION_TYPE
5650 || TREE_CODE (field_type
) == UNION_TYPE
)
5652 else if (!push_fields_onto_fieldstack
5653 (field_type
, fieldstack
, offset
+ foff
)
5654 && (DECL_SIZE (field
)
5655 && !integer_zerop (DECL_SIZE (field
))))
5656 /* Empty structures may have actual size, like in C++. So
5657 see if we didn't push any subfields and the size is
5658 nonzero, push the field onto the stack. */
5663 fieldoff_s
*pair
= NULL
;
5664 bool has_unknown_size
= false;
5665 bool must_have_pointers_p
;
5667 if (!fieldstack
->is_empty ())
5668 pair
= &fieldstack
->last ();
5670 /* If there isn't anything at offset zero, create sth. */
5672 && offset
+ foff
!= 0)
5675 = {0, offset
+ foff
, false, false, true, false, NULL_TREE
};
5676 pair
= fieldstack
->safe_push (e
);
5679 if (!DECL_SIZE (field
)
5680 || !tree_fits_uhwi_p (DECL_SIZE (field
)))
5681 has_unknown_size
= true;
5683 /* If adjacent fields do not contain pointers merge them. */
5684 must_have_pointers_p
= field_must_have_pointers (field
);
5686 && !has_unknown_size
5687 && !must_have_pointers_p
5688 && !pair
->must_have_pointers
5689 && !pair
->has_unknown_size
5690 && pair
->offset
+ (HOST_WIDE_INT
)pair
->size
== offset
+ foff
)
5692 pair
->size
+= tree_to_uhwi (DECL_SIZE (field
));
5697 e
.offset
= offset
+ foff
;
5698 e
.has_unknown_size
= has_unknown_size
;
5699 if (!has_unknown_size
)
5700 e
.size
= tree_to_uhwi (DECL_SIZE (field
));
5703 e
.must_have_pointers
= must_have_pointers_p
;
5704 e
.may_have_pointers
= true;
5705 e
.only_restrict_pointers
5706 = (!has_unknown_size
5707 && POINTER_TYPE_P (field_type
)
5708 && TYPE_RESTRICT (field_type
));
5709 if (e
.only_restrict_pointers
)
5710 e
.restrict_pointed_type
= TREE_TYPE (field_type
);
5711 fieldstack
->safe_push (e
);
5721 /* Count the number of arguments DECL has, and set IS_VARARGS to true
5722 if it is a varargs function. */
5725 count_num_arguments (tree decl
, bool *is_varargs
)
5727 unsigned int num
= 0;
5730 /* Capture named arguments for K&R functions. They do not
5731 have a prototype and thus no TYPE_ARG_TYPES. */
5732 for (t
= DECL_ARGUMENTS (decl
); t
; t
= DECL_CHAIN (t
))
5735 /* Check if the function has variadic arguments. */
5736 for (t
= TYPE_ARG_TYPES (TREE_TYPE (decl
)); t
; t
= TREE_CHAIN (t
))
5737 if (TREE_VALUE (t
) == void_type_node
)
5745 /* Creation function node for DECL, using NAME, and return the index
5746 of the variable we've created for the function. If NONLOCAL_p, create
5747 initial constraints. */
5750 create_function_info_for (tree decl
, const char *name
, bool add_id
,
5753 struct function
*fn
= DECL_STRUCT_FUNCTION (decl
);
5754 varinfo_t vi
, prev_vi
;
5757 bool is_varargs
= false;
5758 unsigned int num_args
= count_num_arguments (decl
, &is_varargs
);
5760 /* Create the variable info. */
5762 vi
= new_var_info (decl
, name
, add_id
);
5765 vi
->fullsize
= fi_parm_base
+ num_args
;
5767 vi
->may_have_pointers
= false;
5770 insert_vi_for_tree (vi
->decl
, vi
);
5774 /* Create a variable for things the function clobbers and one for
5775 things the function uses. */
5777 varinfo_t clobbervi
, usevi
;
5778 const char *newname
;
5781 tempname
= xasprintf ("%s.clobber", name
);
5782 newname
= ggc_strdup (tempname
);
5785 clobbervi
= new_var_info (NULL
, newname
, false);
5786 clobbervi
->offset
= fi_clobbers
;
5787 clobbervi
->size
= 1;
5788 clobbervi
->fullsize
= vi
->fullsize
;
5789 clobbervi
->is_full_var
= true;
5790 clobbervi
->is_global_var
= false;
5791 clobbervi
->is_reg_var
= true;
5793 gcc_assert (prev_vi
->offset
< clobbervi
->offset
);
5794 prev_vi
->next
= clobbervi
->id
;
5795 prev_vi
= clobbervi
;
5797 tempname
= xasprintf ("%s.use", name
);
5798 newname
= ggc_strdup (tempname
);
5801 usevi
= new_var_info (NULL
, newname
, false);
5802 usevi
->offset
= fi_uses
;
5804 usevi
->fullsize
= vi
->fullsize
;
5805 usevi
->is_full_var
= true;
5806 usevi
->is_global_var
= false;
5807 usevi
->is_reg_var
= true;
5809 gcc_assert (prev_vi
->offset
< usevi
->offset
);
5810 prev_vi
->next
= usevi
->id
;
5814 /* And one for the static chain. */
5815 if (fn
->static_chain_decl
!= NULL_TREE
)
5818 const char *newname
;
5821 tempname
= xasprintf ("%s.chain", name
);
5822 newname
= ggc_strdup (tempname
);
5825 chainvi
= new_var_info (fn
->static_chain_decl
, newname
, false);
5826 chainvi
->offset
= fi_static_chain
;
5828 chainvi
->fullsize
= vi
->fullsize
;
5829 chainvi
->is_full_var
= true;
5830 chainvi
->is_global_var
= false;
5832 insert_vi_for_tree (fn
->static_chain_decl
, chainvi
);
5835 && chainvi
->may_have_pointers
)
5836 make_constraint_from (chainvi
, nonlocal_id
);
5838 gcc_assert (prev_vi
->offset
< chainvi
->offset
);
5839 prev_vi
->next
= chainvi
->id
;
5843 /* Create a variable for the return var. */
5844 if (DECL_RESULT (decl
) != NULL
5845 || !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (decl
))))
5848 const char *newname
;
5850 tree resultdecl
= decl
;
5852 if (DECL_RESULT (decl
))
5853 resultdecl
= DECL_RESULT (decl
);
5855 tempname
= xasprintf ("%s.result", name
);
5856 newname
= ggc_strdup (tempname
);
5859 resultvi
= new_var_info (resultdecl
, newname
, false);
5860 resultvi
->offset
= fi_result
;
5862 resultvi
->fullsize
= vi
->fullsize
;
5863 resultvi
->is_full_var
= true;
5864 if (DECL_RESULT (decl
))
5865 resultvi
->may_have_pointers
= true;
5867 if (DECL_RESULT (decl
))
5868 insert_vi_for_tree (DECL_RESULT (decl
), resultvi
);
5871 && DECL_RESULT (decl
)
5872 && DECL_BY_REFERENCE (DECL_RESULT (decl
)))
5873 make_constraint_from (resultvi
, nonlocal_id
);
5875 gcc_assert (prev_vi
->offset
< resultvi
->offset
);
5876 prev_vi
->next
= resultvi
->id
;
5880 /* We also need to make function return values escape. Nothing
5881 escapes by returning from main though. */
5883 && !MAIN_NAME_P (DECL_NAME (decl
)))
5886 fi
= lookup_vi_for_tree (decl
);
5887 rvi
= first_vi_for_offset (fi
, fi_result
);
5888 if (rvi
&& rvi
->offset
== fi_result
)
5889 make_copy_constraint (get_varinfo (escaped_id
), rvi
->id
);
5892 /* Set up variables for each argument. */
5893 arg
= DECL_ARGUMENTS (decl
);
5894 for (i
= 0; i
< num_args
; i
++)
5897 const char *newname
;
5899 tree argdecl
= decl
;
5904 tempname
= xasprintf ("%s.arg%d", name
, i
);
5905 newname
= ggc_strdup (tempname
);
5908 argvi
= new_var_info (argdecl
, newname
, false);
5909 argvi
->offset
= fi_parm_base
+ i
;
5911 argvi
->is_full_var
= true;
5912 argvi
->fullsize
= vi
->fullsize
;
5914 argvi
->may_have_pointers
= true;
5917 insert_vi_for_tree (arg
, argvi
);
5920 && argvi
->may_have_pointers
)
5921 make_constraint_from (argvi
, nonlocal_id
);
5923 gcc_assert (prev_vi
->offset
< argvi
->offset
);
5924 prev_vi
->next
= argvi
->id
;
5927 arg
= DECL_CHAIN (arg
);
5930 /* Add one representative for all further args. */
5934 const char *newname
;
5938 tempname
= xasprintf ("%s.varargs", name
);
5939 newname
= ggc_strdup (tempname
);
5942 /* We need sth that can be pointed to for va_start. */
5943 decl
= build_fake_var_decl (ptr_type_node
);
5945 argvi
= new_var_info (decl
, newname
, false);
5946 argvi
->offset
= fi_parm_base
+ num_args
;
5948 argvi
->is_full_var
= true;
5949 argvi
->is_heap_var
= true;
5950 argvi
->fullsize
= vi
->fullsize
;
5953 && argvi
->may_have_pointers
)
5954 make_constraint_from (argvi
, nonlocal_id
);
5956 gcc_assert (prev_vi
->offset
< argvi
->offset
);
5957 prev_vi
->next
= argvi
->id
;
5965 /* Return true if FIELDSTACK contains fields that overlap.
5966 FIELDSTACK is assumed to be sorted by offset. */
5969 check_for_overlaps (vec
<fieldoff_s
> fieldstack
)
5971 fieldoff_s
*fo
= NULL
;
5973 HOST_WIDE_INT lastoffset
= -1;
5975 FOR_EACH_VEC_ELT (fieldstack
, i
, fo
)
5977 if (fo
->offset
== lastoffset
)
5979 lastoffset
= fo
->offset
;
5984 /* Create a varinfo structure for NAME and DECL, and add it to VARMAP.
5985 This will also create any varinfo structures necessary for fields
5986 of DECL. DECL is a function parameter if HANDLE_PARAM is set.
5987 HANDLED_STRUCT_TYPE is used to register struct types reached by following
5988 restrict pointers. This is needed to prevent infinite recursion.
5989 If ADD_RESTRICT, pretend that the pointer NAME is restrict even if DECL
5990 does not advertise it. */
5993 create_variable_info_for_1 (tree decl
, const char *name
, bool add_id
,
5994 bool handle_param
, bitmap handled_struct_type
,
5995 bool add_restrict
= false)
5997 varinfo_t vi
, newvi
;
5998 tree decl_type
= TREE_TYPE (decl
);
5999 tree declsize
= DECL_P (decl
) ? DECL_SIZE (decl
) : TYPE_SIZE (decl_type
);
6000 auto_vec
<fieldoff_s
> fieldstack
;
6005 || !tree_fits_uhwi_p (declsize
))
6007 vi
= new_var_info (decl
, name
, add_id
);
6011 vi
->is_unknown_size_var
= true;
6012 vi
->is_full_var
= true;
6013 vi
->may_have_pointers
= true;
6017 /* Collect field information. */
6018 if (use_field_sensitive
6019 && var_can_have_subvars (decl
)
6020 /* ??? Force us to not use subfields for globals in IPA mode.
6021 Else we'd have to parse arbitrary initializers. */
6023 && is_global_var (decl
)))
6025 fieldoff_s
*fo
= NULL
;
6026 bool notokay
= false;
6029 push_fields_onto_fieldstack (decl_type
, &fieldstack
, 0);
6031 for (i
= 0; !notokay
&& fieldstack
.iterate (i
, &fo
); i
++)
6032 if (fo
->has_unknown_size
6039 /* We can't sort them if we have a field with a variable sized type,
6040 which will make notokay = true. In that case, we are going to return
6041 without creating varinfos for the fields anyway, so sorting them is a
6045 sort_fieldstack (fieldstack
);
6046 /* Due to some C++ FE issues, like PR 22488, we might end up
6047 what appear to be overlapping fields even though they,
6048 in reality, do not overlap. Until the C++ FE is fixed,
6049 we will simply disable field-sensitivity for these cases. */
6050 notokay
= check_for_overlaps (fieldstack
);
6054 fieldstack
.release ();
6057 /* If we didn't end up collecting sub-variables create a full
6058 variable for the decl. */
6059 if (fieldstack
.length () == 0
6060 || fieldstack
.length () > MAX_FIELDS_FOR_FIELD_SENSITIVE
)
6062 vi
= new_var_info (decl
, name
, add_id
);
6064 vi
->may_have_pointers
= true;
6065 vi
->fullsize
= tree_to_uhwi (declsize
);
6066 vi
->size
= vi
->fullsize
;
6067 vi
->is_full_var
= true;
6068 if (POINTER_TYPE_P (decl_type
)
6069 && (TYPE_RESTRICT (decl_type
) || add_restrict
))
6070 vi
->only_restrict_pointers
= 1;
6071 if (vi
->only_restrict_pointers
6072 && !type_contains_placeholder_p (TREE_TYPE (decl_type
))
6074 && !bitmap_bit_p (handled_struct_type
,
6075 TYPE_UID (TREE_TYPE (decl_type
))))
6078 tree heapvar
= build_fake_var_decl (TREE_TYPE (decl_type
));
6079 DECL_EXTERNAL (heapvar
) = 1;
6080 if (var_can_have_subvars (heapvar
))
6081 bitmap_set_bit (handled_struct_type
,
6082 TYPE_UID (TREE_TYPE (decl_type
)));
6083 rvi
= create_variable_info_for_1 (heapvar
, "PARM_NOALIAS", true,
6084 true, handled_struct_type
);
6085 if (var_can_have_subvars (heapvar
))
6086 bitmap_clear_bit (handled_struct_type
,
6087 TYPE_UID (TREE_TYPE (decl_type
)));
6088 rvi
->is_restrict_var
= 1;
6089 insert_vi_for_tree (heapvar
, rvi
);
6090 make_constraint_from (vi
, rvi
->id
);
6091 make_param_constraints (rvi
);
6093 fieldstack
.release ();
6097 vi
= new_var_info (decl
, name
, add_id
);
6098 vi
->fullsize
= tree_to_uhwi (declsize
);
6099 if (fieldstack
.length () == 1)
6100 vi
->is_full_var
= true;
6101 for (i
= 0, newvi
= vi
;
6102 fieldstack
.iterate (i
, &fo
);
6103 ++i
, newvi
= vi_next (newvi
))
6105 const char *newname
= NULL
;
6110 if (fieldstack
.length () != 1)
6113 = xasprintf ("%s." HOST_WIDE_INT_PRINT_DEC
6114 "+" HOST_WIDE_INT_PRINT_DEC
, name
,
6115 fo
->offset
, fo
->size
);
6116 newname
= ggc_strdup (tempname
);
6124 newvi
->name
= newname
;
6125 newvi
->offset
= fo
->offset
;
6126 newvi
->size
= fo
->size
;
6127 newvi
->fullsize
= vi
->fullsize
;
6128 newvi
->may_have_pointers
= fo
->may_have_pointers
;
6129 newvi
->only_restrict_pointers
= fo
->only_restrict_pointers
;
6131 && newvi
->only_restrict_pointers
6132 && !type_contains_placeholder_p (fo
->restrict_pointed_type
)
6133 && !bitmap_bit_p (handled_struct_type
,
6134 TYPE_UID (fo
->restrict_pointed_type
)))
6137 tree heapvar
= build_fake_var_decl (fo
->restrict_pointed_type
);
6138 DECL_EXTERNAL (heapvar
) = 1;
6139 if (var_can_have_subvars (heapvar
))
6140 bitmap_set_bit (handled_struct_type
,
6141 TYPE_UID (fo
->restrict_pointed_type
));
6142 rvi
= create_variable_info_for_1 (heapvar
, "PARM_NOALIAS", true,
6143 true, handled_struct_type
);
6144 if (var_can_have_subvars (heapvar
))
6145 bitmap_clear_bit (handled_struct_type
,
6146 TYPE_UID (fo
->restrict_pointed_type
));
6147 rvi
->is_restrict_var
= 1;
6148 insert_vi_for_tree (heapvar
, rvi
);
6149 make_constraint_from (newvi
, rvi
->id
);
6150 make_param_constraints (rvi
);
6152 if (i
+ 1 < fieldstack
.length ())
6154 varinfo_t tem
= new_var_info (decl
, name
, false);
6155 newvi
->next
= tem
->id
;
6164 create_variable_info_for (tree decl
, const char *name
, bool add_id
)
6166 /* First see if we are dealing with an ifunc resolver call and
6167 assiociate that with a call to the resolver function result. */
6170 && TREE_CODE (decl
) == FUNCTION_DECL
6171 && (node
= cgraph_node::get (decl
))
6172 && node
->ifunc_resolver
)
6174 varinfo_t fi
= get_vi_for_tree (node
->get_alias_target ()->decl
);
6176 = get_function_part_constraint (fi
, fi_result
);
6177 fi
= new_var_info (NULL_TREE
, "ifuncres", true);
6178 fi
->is_reg_var
= true;
6179 constraint_expr lhs
;
6183 process_constraint (new_constraint (lhs
, rhs
));
6184 insert_vi_for_tree (decl
, fi
);
6188 varinfo_t vi
= create_variable_info_for_1 (decl
, name
, add_id
, false, NULL
);
6189 unsigned int id
= vi
->id
;
6191 insert_vi_for_tree (decl
, vi
);
6196 /* Create initial constraints for globals. */
6197 for (; vi
; vi
= vi_next (vi
))
6199 if (!vi
->may_have_pointers
6200 || !vi
->is_global_var
)
6203 /* Mark global restrict qualified pointers. */
6204 if ((POINTER_TYPE_P (TREE_TYPE (decl
))
6205 && TYPE_RESTRICT (TREE_TYPE (decl
)))
6206 || vi
->only_restrict_pointers
)
6209 = make_constraint_from_global_restrict (vi
, "GLOBAL_RESTRICT",
6211 /* ??? For now exclude reads from globals as restrict sources
6212 if those are not (indirectly) from incoming parameters. */
6213 rvi
->is_restrict_var
= false;
6217 /* In non-IPA mode the initializer from nonlocal is all we need. */
6219 || DECL_HARD_REGISTER (decl
))
6220 make_copy_constraint (vi
, nonlocal_id
);
6222 /* In IPA mode parse the initializer and generate proper constraints
6226 varpool_node
*vnode
= varpool_node::get (decl
);
6228 /* For escaped variables initialize them from nonlocal. */
6229 if (!vnode
->all_refs_explicit_p ())
6230 make_copy_constraint (vi
, nonlocal_id
);
6232 /* If this is a global variable with an initializer and we are in
6233 IPA mode generate constraints for it. */
6235 for (unsigned idx
= 0; vnode
->iterate_reference (idx
, ref
); ++idx
)
6237 auto_vec
<ce_s
> rhsc
;
6238 struct constraint_expr lhs
, *rhsp
;
6240 get_constraint_for_address_of (ref
->referred
->decl
, &rhsc
);
6244 FOR_EACH_VEC_ELT (rhsc
, i
, rhsp
)
6245 process_constraint (new_constraint (lhs
, *rhsp
));
6246 /* If this is a variable that escapes from the unit
6247 the initializer escapes as well. */
6248 if (!vnode
->all_refs_explicit_p ())
6250 lhs
.var
= escaped_id
;
6253 FOR_EACH_VEC_ELT (rhsc
, i
, rhsp
)
6254 process_constraint (new_constraint (lhs
, *rhsp
));
6263 /* Print out the points-to solution for VAR to FILE. */
6266 dump_solution_for_var (FILE *file
, unsigned int var
)
6268 varinfo_t vi
= get_varinfo (var
);
6272 /* Dump the solution for unified vars anyway, this avoids difficulties
6273 in scanning dumps in the testsuite. */
6274 fprintf (file
, "%s = { ", vi
->name
);
6275 vi
= get_varinfo (find (var
));
6276 EXECUTE_IF_SET_IN_BITMAP (vi
->solution
, 0, i
, bi
)
6277 fprintf (file
, "%s ", get_varinfo (i
)->name
);
6278 fprintf (file
, "}");
6280 /* But note when the variable was unified. */
6282 fprintf (file
, " same as %s", vi
->name
);
6284 fprintf (file
, "\n");
6287 /* Print the points-to solution for VAR to stderr. */
6290 debug_solution_for_var (unsigned int var
)
6292 dump_solution_for_var (stderr
, var
);
6295 /* Register the constraints for function parameter related VI. */
6298 make_param_constraints (varinfo_t vi
)
6300 for (; vi
; vi
= vi_next (vi
))
6302 if (vi
->only_restrict_pointers
)
6304 else if (vi
->may_have_pointers
)
6305 make_constraint_from (vi
, nonlocal_id
);
6307 if (vi
->is_full_var
)
6312 /* Create varinfo structures for all of the variables in the
6313 function for intraprocedural mode. */
6316 intra_create_variable_infos (struct function
*fn
)
6319 bitmap handled_struct_type
= NULL
;
6320 bool this_parm_in_ctor
= DECL_CXX_CONSTRUCTOR_P (fn
->decl
);
6322 /* For each incoming pointer argument arg, create the constraint ARG
6323 = NONLOCAL or a dummy variable if it is a restrict qualified
6324 passed-by-reference argument. */
6325 for (t
= DECL_ARGUMENTS (fn
->decl
); t
; t
= DECL_CHAIN (t
))
6327 if (handled_struct_type
== NULL
)
6328 handled_struct_type
= BITMAP_ALLOC (NULL
);
6331 = create_variable_info_for_1 (t
, alias_get_name (t
), false, true,
6332 handled_struct_type
, this_parm_in_ctor
);
6333 insert_vi_for_tree (t
, p
);
6335 make_param_constraints (p
);
6337 this_parm_in_ctor
= false;
6340 if (handled_struct_type
!= NULL
)
6341 BITMAP_FREE (handled_struct_type
);
6343 /* Add a constraint for a result decl that is passed by reference. */
6344 if (DECL_RESULT (fn
->decl
)
6345 && DECL_BY_REFERENCE (DECL_RESULT (fn
->decl
)))
6347 varinfo_t p
, result_vi
= get_vi_for_tree (DECL_RESULT (fn
->decl
));
6349 for (p
= result_vi
; p
; p
= vi_next (p
))
6350 make_constraint_from (p
, nonlocal_id
);
6353 /* Add a constraint for the incoming static chain parameter. */
6354 if (fn
->static_chain_decl
!= NULL_TREE
)
6356 varinfo_t p
, chain_vi
= get_vi_for_tree (fn
->static_chain_decl
);
6358 for (p
= chain_vi
; p
; p
= vi_next (p
))
6359 make_constraint_from (p
, nonlocal_id
);
6363 /* Structure used to put solution bitmaps in a hashtable so they can
6364 be shared among variables with the same points-to set. */
6366 typedef struct shared_bitmap_info
6370 } *shared_bitmap_info_t
;
6371 typedef const struct shared_bitmap_info
*const_shared_bitmap_info_t
;
6373 /* Shared_bitmap hashtable helpers. */
6375 struct shared_bitmap_hasher
: free_ptr_hash
<shared_bitmap_info
>
6377 static inline hashval_t
hash (const shared_bitmap_info
*);
6378 static inline bool equal (const shared_bitmap_info
*,
6379 const shared_bitmap_info
*);
6382 /* Hash function for a shared_bitmap_info_t */
6385 shared_bitmap_hasher::hash (const shared_bitmap_info
*bi
)
6387 return bi
->hashcode
;
6390 /* Equality function for two shared_bitmap_info_t's. */
6393 shared_bitmap_hasher::equal (const shared_bitmap_info
*sbi1
,
6394 const shared_bitmap_info
*sbi2
)
6396 return bitmap_equal_p (sbi1
->pt_vars
, sbi2
->pt_vars
);
6399 /* Shared_bitmap hashtable. */
6401 static hash_table
<shared_bitmap_hasher
> *shared_bitmap_table
;
6403 /* Lookup a bitmap in the shared bitmap hashtable, and return an already
6404 existing instance if there is one, NULL otherwise. */
6407 shared_bitmap_lookup (bitmap pt_vars
)
6409 shared_bitmap_info
**slot
;
6410 struct shared_bitmap_info sbi
;
6412 sbi
.pt_vars
= pt_vars
;
6413 sbi
.hashcode
= bitmap_hash (pt_vars
);
6415 slot
= shared_bitmap_table
->find_slot (&sbi
, NO_INSERT
);
6419 return (*slot
)->pt_vars
;
6423 /* Add a bitmap to the shared bitmap hashtable. */
6426 shared_bitmap_add (bitmap pt_vars
)
6428 shared_bitmap_info
**slot
;
6429 shared_bitmap_info_t sbi
= XNEW (struct shared_bitmap_info
);
6431 sbi
->pt_vars
= pt_vars
;
6432 sbi
->hashcode
= bitmap_hash (pt_vars
);
6434 slot
= shared_bitmap_table
->find_slot (sbi
, INSERT
);
6435 gcc_assert (!*slot
);
6440 /* Set bits in INTO corresponding to the variable uids in solution set FROM. */
6443 set_uids_in_ptset (bitmap into
, bitmap from
, struct pt_solution
*pt
,
6448 varinfo_t escaped_vi
= get_varinfo (find (escaped_id
));
6449 bool everything_escaped
6450 = escaped_vi
->solution
&& bitmap_bit_p (escaped_vi
->solution
, anything_id
);
6452 EXECUTE_IF_SET_IN_BITMAP (from
, 0, i
, bi
)
6454 varinfo_t vi
= get_varinfo (i
);
6456 if (vi
->is_artificial_var
)
6459 if (everything_escaped
6460 || (escaped_vi
->solution
6461 && bitmap_bit_p (escaped_vi
->solution
, i
)))
6463 pt
->vars_contains_escaped
= true;
6464 pt
->vars_contains_escaped_heap
|= vi
->is_heap_var
;
6467 if (vi
->is_restrict_var
)
6468 pt
->vars_contains_restrict
= true;
6470 if (VAR_P (vi
->decl
)
6471 || TREE_CODE (vi
->decl
) == PARM_DECL
6472 || TREE_CODE (vi
->decl
) == RESULT_DECL
)
6474 /* If we are in IPA mode we will not recompute points-to
6475 sets after inlining so make sure they stay valid. */
6477 && !DECL_PT_UID_SET_P (vi
->decl
))
6478 SET_DECL_PT_UID (vi
->decl
, DECL_UID (vi
->decl
));
6480 /* Add the decl to the points-to set. Note that the points-to
6481 set contains global variables. */
6482 bitmap_set_bit (into
, DECL_PT_UID (vi
->decl
));
6483 if (vi
->is_global_var
6484 /* In IPA mode the escaped_heap trick doesn't work as
6485 ESCAPED is escaped from the unit but
6486 pt_solution_includes_global needs to answer true for
6487 all variables not automatic within a function.
6488 For the same reason is_global_var is not the
6489 correct flag to track - local variables from other
6490 functions also need to be considered global.
6491 Conveniently all HEAP vars are not put in function
6495 && ! auto_var_in_fn_p (vi
->decl
, fndecl
)))
6496 pt
->vars_contains_nonlocal
= true;
6498 /* If we have a variable that is interposable record that fact
6499 for pointer comparison simplification. */
6500 if (VAR_P (vi
->decl
)
6501 && (TREE_STATIC (vi
->decl
) || DECL_EXTERNAL (vi
->decl
))
6502 && ! decl_binds_to_current_def_p (vi
->decl
))
6503 pt
->vars_contains_interposable
= true;
6505 /* If this is a local variable we can have overlapping lifetime
6506 of different function invocations through recursion duplicate
6507 it with its shadow variable. */
6509 && vi
->shadow_var_uid
!= 0)
6511 bitmap_set_bit (into
, vi
->shadow_var_uid
);
6512 pt
->vars_contains_nonlocal
= true;
6516 else if (TREE_CODE (vi
->decl
) == FUNCTION_DECL
6517 || TREE_CODE (vi
->decl
) == LABEL_DECL
)
6519 /* Nothing should read/write from/to code so we can
6520 save bits by not including them in the points-to bitmaps.
6521 Still mark the points-to set as containing global memory
6522 to make code-patching possible - see PR70128. */
6523 pt
->vars_contains_nonlocal
= true;
6529 /* Compute the points-to solution *PT for the variable VI. */
6531 static struct pt_solution
6532 find_what_var_points_to (tree fndecl
, varinfo_t orig_vi
)
6536 bitmap finished_solution
;
6539 struct pt_solution
*pt
;
6541 /* This variable may have been collapsed, let's get the real
6543 vi
= get_varinfo (find (orig_vi
->id
));
6545 /* See if we have already computed the solution and return it. */
6546 pt_solution
**slot
= &final_solutions
->get_or_insert (vi
);
6550 *slot
= pt
= XOBNEW (&final_solutions_obstack
, struct pt_solution
);
6551 memset (pt
, 0, sizeof (struct pt_solution
));
6553 /* Translate artificial variables into SSA_NAME_PTR_INFO
6555 EXECUTE_IF_SET_IN_BITMAP (vi
->solution
, 0, i
, bi
)
6557 varinfo_t vi
= get_varinfo (i
);
6559 if (vi
->is_artificial_var
)
6561 if (vi
->id
== nothing_id
)
6563 else if (vi
->id
== escaped_id
)
6566 pt
->ipa_escaped
= 1;
6569 /* Expand some special vars of ESCAPED in-place here. */
6570 varinfo_t evi
= get_varinfo (find (escaped_id
));
6571 if (bitmap_bit_p (evi
->solution
, nonlocal_id
))
6574 else if (vi
->id
== nonlocal_id
)
6576 else if (vi
->id
== string_id
)
6577 /* Nobody cares - STRING_CSTs are read-only entities. */
6579 else if (vi
->id
== anything_id
6580 || vi
->id
== integer_id
)
6585 /* Instead of doing extra work, simply do not create
6586 elaborate points-to information for pt_anything pointers. */
6590 /* Share the final set of variables when possible. */
6591 finished_solution
= BITMAP_GGC_ALLOC ();
6592 stats
.points_to_sets_created
++;
6594 set_uids_in_ptset (finished_solution
, vi
->solution
, pt
, fndecl
);
6595 result
= shared_bitmap_lookup (finished_solution
);
6598 shared_bitmap_add (finished_solution
);
6599 pt
->vars
= finished_solution
;
6604 bitmap_clear (finished_solution
);
6610 /* Given a pointer variable P, fill in its points-to set. */
6613 find_what_p_points_to (tree fndecl
, tree p
)
6615 struct ptr_info_def
*pi
;
6618 bool nonnull
= get_ptr_nonnull (p
);
6620 /* For parameters, get at the points-to set for the actual parm
6622 if (TREE_CODE (p
) == SSA_NAME
6623 && SSA_NAME_IS_DEFAULT_DEF (p
)
6624 && (TREE_CODE (SSA_NAME_VAR (p
)) == PARM_DECL
6625 || TREE_CODE (SSA_NAME_VAR (p
)) == RESULT_DECL
))
6626 lookup_p
= SSA_NAME_VAR (p
);
6628 vi
= lookup_vi_for_tree (lookup_p
);
6632 pi
= get_ptr_info (p
);
6633 pi
->pt
= find_what_var_points_to (fndecl
, vi
);
6634 /* Conservatively set to NULL from PTA (to true). */
6636 /* Preserve pointer nonnull computed by VRP. See get_ptr_nonnull
6637 in gcc/tree-ssaname.c for more information. */
6639 set_ptr_nonnull (p
);
6643 /* Query statistics for points-to solutions. */
6646 unsigned HOST_WIDE_INT pt_solution_includes_may_alias
;
6647 unsigned HOST_WIDE_INT pt_solution_includes_no_alias
;
6648 unsigned HOST_WIDE_INT pt_solutions_intersect_may_alias
;
6649 unsigned HOST_WIDE_INT pt_solutions_intersect_no_alias
;
6653 dump_pta_stats (FILE *s
)
6655 fprintf (s
, "\nPTA query stats:\n");
6656 fprintf (s
, " pt_solution_includes: "
6657 HOST_WIDE_INT_PRINT_DEC
" disambiguations, "
6658 HOST_WIDE_INT_PRINT_DEC
" queries\n",
6659 pta_stats
.pt_solution_includes_no_alias
,
6660 pta_stats
.pt_solution_includes_no_alias
6661 + pta_stats
.pt_solution_includes_may_alias
);
6662 fprintf (s
, " pt_solutions_intersect: "
6663 HOST_WIDE_INT_PRINT_DEC
" disambiguations, "
6664 HOST_WIDE_INT_PRINT_DEC
" queries\n",
6665 pta_stats
.pt_solutions_intersect_no_alias
,
6666 pta_stats
.pt_solutions_intersect_no_alias
6667 + pta_stats
.pt_solutions_intersect_may_alias
);
6671 /* Reset the points-to solution *PT to a conservative default
6672 (point to anything). */
6675 pt_solution_reset (struct pt_solution
*pt
)
6677 memset (pt
, 0, sizeof (struct pt_solution
));
6678 pt
->anything
= true;
6682 /* Set the points-to solution *PT to point only to the variables
6683 in VARS. VARS_CONTAINS_GLOBAL specifies whether that contains
6684 global variables and VARS_CONTAINS_RESTRICT specifies whether
6685 it contains restrict tag variables. */
6688 pt_solution_set (struct pt_solution
*pt
, bitmap vars
,
6689 bool vars_contains_nonlocal
)
6691 memset (pt
, 0, sizeof (struct pt_solution
));
6693 pt
->vars_contains_nonlocal
= vars_contains_nonlocal
;
6694 pt
->vars_contains_escaped
6695 = (cfun
->gimple_df
->escaped
.anything
6696 || bitmap_intersect_p (cfun
->gimple_df
->escaped
.vars
, vars
));
6699 /* Set the points-to solution *PT to point only to the variable VAR. */
6702 pt_solution_set_var (struct pt_solution
*pt
, tree var
)
6704 memset (pt
, 0, sizeof (struct pt_solution
));
6705 pt
->vars
= BITMAP_GGC_ALLOC ();
6706 bitmap_set_bit (pt
->vars
, DECL_PT_UID (var
));
6707 pt
->vars_contains_nonlocal
= is_global_var (var
);
6708 pt
->vars_contains_escaped
6709 = (cfun
->gimple_df
->escaped
.anything
6710 || bitmap_bit_p (cfun
->gimple_df
->escaped
.vars
, DECL_PT_UID (var
)));
6713 /* Computes the union of the points-to solutions *DEST and *SRC and
6714 stores the result in *DEST. This changes the points-to bitmap
6715 of *DEST and thus may not be used if that might be shared.
6716 The points-to bitmap of *SRC and *DEST will not be shared after
6717 this function if they were not before. */
6720 pt_solution_ior_into (struct pt_solution
*dest
, struct pt_solution
*src
)
6722 dest
->anything
|= src
->anything
;
6725 pt_solution_reset (dest
);
6729 dest
->nonlocal
|= src
->nonlocal
;
6730 dest
->escaped
|= src
->escaped
;
6731 dest
->ipa_escaped
|= src
->ipa_escaped
;
6732 dest
->null
|= src
->null
;
6733 dest
->vars_contains_nonlocal
|= src
->vars_contains_nonlocal
;
6734 dest
->vars_contains_escaped
|= src
->vars_contains_escaped
;
6735 dest
->vars_contains_escaped_heap
|= src
->vars_contains_escaped_heap
;
6740 dest
->vars
= BITMAP_GGC_ALLOC ();
6741 bitmap_ior_into (dest
->vars
, src
->vars
);
6744 /* Return true if the points-to solution *PT is empty. */
6747 pt_solution_empty_p (struct pt_solution
*pt
)
6754 && !bitmap_empty_p (pt
->vars
))
6757 /* If the solution includes ESCAPED, check if that is empty. */
6759 && !pt_solution_empty_p (&cfun
->gimple_df
->escaped
))
6762 /* If the solution includes ESCAPED, check if that is empty. */
6764 && !pt_solution_empty_p (&ipa_escaped_pt
))
6770 /* Return true if the points-to solution *PT only point to a single var, and
6771 return the var uid in *UID. */
6774 pt_solution_singleton_or_null_p (struct pt_solution
*pt
, unsigned *uid
)
6776 if (pt
->anything
|| pt
->nonlocal
|| pt
->escaped
|| pt
->ipa_escaped
6778 || !bitmap_single_bit_set_p (pt
->vars
))
6781 *uid
= bitmap_first_set_bit (pt
->vars
);
6785 /* Return true if the points-to solution *PT includes global memory. */
6788 pt_solution_includes_global (struct pt_solution
*pt
)
6792 || pt
->vars_contains_nonlocal
6793 /* The following is a hack to make the malloc escape hack work.
6794 In reality we'd need different sets for escaped-through-return
6795 and escaped-to-callees and passes would need to be updated. */
6796 || pt
->vars_contains_escaped_heap
)
6799 /* 'escaped' is also a placeholder so we have to look into it. */
6801 return pt_solution_includes_global (&cfun
->gimple_df
->escaped
);
6803 if (pt
->ipa_escaped
)
6804 return pt_solution_includes_global (&ipa_escaped_pt
);
6809 /* Return true if the points-to solution *PT includes the variable
6810 declaration DECL. */
6813 pt_solution_includes_1 (struct pt_solution
*pt
, const_tree decl
)
6819 && is_global_var (decl
))
6823 && bitmap_bit_p (pt
->vars
, DECL_PT_UID (decl
)))
6826 /* If the solution includes ESCAPED, check it. */
6828 && pt_solution_includes_1 (&cfun
->gimple_df
->escaped
, decl
))
6831 /* If the solution includes ESCAPED, check it. */
6833 && pt_solution_includes_1 (&ipa_escaped_pt
, decl
))
6840 pt_solution_includes (struct pt_solution
*pt
, const_tree decl
)
6842 bool res
= pt_solution_includes_1 (pt
, decl
);
6844 ++pta_stats
.pt_solution_includes_may_alias
;
6846 ++pta_stats
.pt_solution_includes_no_alias
;
6850 /* Return true if both points-to solutions PT1 and PT2 have a non-empty
6854 pt_solutions_intersect_1 (struct pt_solution
*pt1
, struct pt_solution
*pt2
)
6856 if (pt1
->anything
|| pt2
->anything
)
6859 /* If either points to unknown global memory and the other points to
6860 any global memory they alias. */
6863 || pt2
->vars_contains_nonlocal
))
6865 && pt1
->vars_contains_nonlocal
))
6868 /* If either points to all escaped memory and the other points to
6869 any escaped memory they alias. */
6872 || pt2
->vars_contains_escaped
))
6874 && pt1
->vars_contains_escaped
))
6877 /* Check the escaped solution if required.
6878 ??? Do we need to check the local against the IPA escaped sets? */
6879 if ((pt1
->ipa_escaped
|| pt2
->ipa_escaped
)
6880 && !pt_solution_empty_p (&ipa_escaped_pt
))
6882 /* If both point to escaped memory and that solution
6883 is not empty they alias. */
6884 if (pt1
->ipa_escaped
&& pt2
->ipa_escaped
)
6887 /* If either points to escaped memory see if the escaped solution
6888 intersects with the other. */
6889 if ((pt1
->ipa_escaped
6890 && pt_solutions_intersect_1 (&ipa_escaped_pt
, pt2
))
6891 || (pt2
->ipa_escaped
6892 && pt_solutions_intersect_1 (&ipa_escaped_pt
, pt1
)))
6896 /* Now both pointers alias if their points-to solution intersects. */
6899 && bitmap_intersect_p (pt1
->vars
, pt2
->vars
));
6903 pt_solutions_intersect (struct pt_solution
*pt1
, struct pt_solution
*pt2
)
6905 bool res
= pt_solutions_intersect_1 (pt1
, pt2
);
6907 ++pta_stats
.pt_solutions_intersect_may_alias
;
6909 ++pta_stats
.pt_solutions_intersect_no_alias
;
6914 /* Dump points-to information to OUTFILE. */
6917 dump_sa_points_to_info (FILE *outfile
)
6921 fprintf (outfile
, "\nPoints-to sets\n\n");
6923 if (dump_flags
& TDF_STATS
)
6925 fprintf (outfile
, "Stats:\n");
6926 fprintf (outfile
, "Total vars: %d\n", stats
.total_vars
);
6927 fprintf (outfile
, "Non-pointer vars: %d\n",
6928 stats
.nonpointer_vars
);
6929 fprintf (outfile
, "Statically unified vars: %d\n",
6930 stats
.unified_vars_static
);
6931 fprintf (outfile
, "Dynamically unified vars: %d\n",
6932 stats
.unified_vars_dynamic
);
6933 fprintf (outfile
, "Iterations: %d\n", stats
.iterations
);
6934 fprintf (outfile
, "Number of edges: %d\n", stats
.num_edges
);
6935 fprintf (outfile
, "Number of implicit edges: %d\n",
6936 stats
.num_implicit_edges
);
6939 for (i
= 1; i
< varmap
.length (); i
++)
6941 varinfo_t vi
= get_varinfo (i
);
6942 if (!vi
->may_have_pointers
)
6944 dump_solution_for_var (outfile
, i
);
6949 /* Debug points-to information to stderr. */
6952 debug_sa_points_to_info (void)
6954 dump_sa_points_to_info (stderr
);
6958 /* Initialize the always-existing constraint variables for NULL
6959 ANYTHING, READONLY, and INTEGER */
6962 init_base_vars (void)
6964 struct constraint_expr lhs
, rhs
;
6965 varinfo_t var_anything
;
6966 varinfo_t var_nothing
;
6967 varinfo_t var_string
;
6968 varinfo_t var_escaped
;
6969 varinfo_t var_nonlocal
;
6970 varinfo_t var_storedanything
;
6971 varinfo_t var_integer
;
6973 /* Variable ID zero is reserved and should be NULL. */
6974 varmap
.safe_push (NULL
);
6976 /* Create the NULL variable, used to represent that a variable points
6978 var_nothing
= new_var_info (NULL_TREE
, "NULL", false);
6979 gcc_assert (var_nothing
->id
== nothing_id
);
6980 var_nothing
->is_artificial_var
= 1;
6981 var_nothing
->offset
= 0;
6982 var_nothing
->size
= ~0;
6983 var_nothing
->fullsize
= ~0;
6984 var_nothing
->is_special_var
= 1;
6985 var_nothing
->may_have_pointers
= 0;
6986 var_nothing
->is_global_var
= 0;
6988 /* Create the ANYTHING variable, used to represent that a variable
6989 points to some unknown piece of memory. */
6990 var_anything
= new_var_info (NULL_TREE
, "ANYTHING", false);
6991 gcc_assert (var_anything
->id
== anything_id
);
6992 var_anything
->is_artificial_var
= 1;
6993 var_anything
->size
= ~0;
6994 var_anything
->offset
= 0;
6995 var_anything
->fullsize
= ~0;
6996 var_anything
->is_special_var
= 1;
6998 /* Anything points to anything. This makes deref constraints just
6999 work in the presence of linked list and other p = *p type loops,
7000 by saying that *ANYTHING = ANYTHING. */
7002 lhs
.var
= anything_id
;
7004 rhs
.type
= ADDRESSOF
;
7005 rhs
.var
= anything_id
;
7008 /* This specifically does not use process_constraint because
7009 process_constraint ignores all anything = anything constraints, since all
7010 but this one are redundant. */
7011 constraints
.safe_push (new_constraint (lhs
, rhs
));
7013 /* Create the STRING variable, used to represent that a variable
7014 points to a string literal. String literals don't contain
7015 pointers so STRING doesn't point to anything. */
7016 var_string
= new_var_info (NULL_TREE
, "STRING", false);
7017 gcc_assert (var_string
->id
== string_id
);
7018 var_string
->is_artificial_var
= 1;
7019 var_string
->offset
= 0;
7020 var_string
->size
= ~0;
7021 var_string
->fullsize
= ~0;
7022 var_string
->is_special_var
= 1;
7023 var_string
->may_have_pointers
= 0;
7025 /* Create the ESCAPED variable, used to represent the set of escaped
7027 var_escaped
= new_var_info (NULL_TREE
, "ESCAPED", false);
7028 gcc_assert (var_escaped
->id
== escaped_id
);
7029 var_escaped
->is_artificial_var
= 1;
7030 var_escaped
->offset
= 0;
7031 var_escaped
->size
= ~0;
7032 var_escaped
->fullsize
= ~0;
7033 var_escaped
->is_special_var
= 0;
7035 /* Create the NONLOCAL variable, used to represent the set of nonlocal
7037 var_nonlocal
= new_var_info (NULL_TREE
, "NONLOCAL", false);
7038 gcc_assert (var_nonlocal
->id
== nonlocal_id
);
7039 var_nonlocal
->is_artificial_var
= 1;
7040 var_nonlocal
->offset
= 0;
7041 var_nonlocal
->size
= ~0;
7042 var_nonlocal
->fullsize
= ~0;
7043 var_nonlocal
->is_special_var
= 1;
7045 /* ESCAPED = *ESCAPED, because escaped is may-deref'd at calls, etc. */
7047 lhs
.var
= escaped_id
;
7050 rhs
.var
= escaped_id
;
7052 process_constraint (new_constraint (lhs
, rhs
));
7054 /* ESCAPED = ESCAPED + UNKNOWN_OFFSET, because if a sub-field escapes the
7055 whole variable escapes. */
7057 lhs
.var
= escaped_id
;
7060 rhs
.var
= escaped_id
;
7061 rhs
.offset
= UNKNOWN_OFFSET
;
7062 process_constraint (new_constraint (lhs
, rhs
));
7064 /* *ESCAPED = NONLOCAL. This is true because we have to assume
7065 everything pointed to by escaped points to what global memory can
7068 lhs
.var
= escaped_id
;
7071 rhs
.var
= nonlocal_id
;
7073 process_constraint (new_constraint (lhs
, rhs
));
7075 /* NONLOCAL = &NONLOCAL, NONLOCAL = &ESCAPED. This is true because
7076 global memory may point to global memory and escaped memory. */
7078 lhs
.var
= nonlocal_id
;
7080 rhs
.type
= ADDRESSOF
;
7081 rhs
.var
= nonlocal_id
;
7083 process_constraint (new_constraint (lhs
, rhs
));
7084 rhs
.type
= ADDRESSOF
;
7085 rhs
.var
= escaped_id
;
7087 process_constraint (new_constraint (lhs
, rhs
));
7089 /* Create the STOREDANYTHING variable, used to represent the set of
7090 variables stored to *ANYTHING. */
7091 var_storedanything
= new_var_info (NULL_TREE
, "STOREDANYTHING", false);
7092 gcc_assert (var_storedanything
->id
== storedanything_id
);
7093 var_storedanything
->is_artificial_var
= 1;
7094 var_storedanything
->offset
= 0;
7095 var_storedanything
->size
= ~0;
7096 var_storedanything
->fullsize
= ~0;
7097 var_storedanything
->is_special_var
= 0;
7099 /* Create the INTEGER variable, used to represent that a variable points
7100 to what an INTEGER "points to". */
7101 var_integer
= new_var_info (NULL_TREE
, "INTEGER", false);
7102 gcc_assert (var_integer
->id
== integer_id
);
7103 var_integer
->is_artificial_var
= 1;
7104 var_integer
->size
= ~0;
7105 var_integer
->fullsize
= ~0;
7106 var_integer
->offset
= 0;
7107 var_integer
->is_special_var
= 1;
7109 /* INTEGER = ANYTHING, because we don't know where a dereference of
7110 a random integer will point to. */
7112 lhs
.var
= integer_id
;
7114 rhs
.type
= ADDRESSOF
;
7115 rhs
.var
= anything_id
;
7117 process_constraint (new_constraint (lhs
, rhs
));
7120 /* Initialize things necessary to perform PTA */
7123 init_alias_vars (void)
7125 use_field_sensitive
= (MAX_FIELDS_FOR_FIELD_SENSITIVE
> 1);
7127 bitmap_obstack_initialize (&pta_obstack
);
7128 bitmap_obstack_initialize (&oldpta_obstack
);
7129 bitmap_obstack_initialize (&predbitmap_obstack
);
7131 constraints
.create (8);
7133 vi_for_tree
= new hash_map
<tree
, varinfo_t
>;
7134 call_stmt_vars
= new hash_map
<gimple
*, varinfo_t
>;
7136 memset (&stats
, 0, sizeof (stats
));
7137 shared_bitmap_table
= new hash_table
<shared_bitmap_hasher
> (511);
7140 gcc_obstack_init (&fake_var_decl_obstack
);
7142 final_solutions
= new hash_map
<varinfo_t
, pt_solution
*>;
7143 gcc_obstack_init (&final_solutions_obstack
);
7146 /* Remove the REF and ADDRESS edges from GRAPH, as well as all the
7147 predecessor edges. */
7150 remove_preds_and_fake_succs (constraint_graph_t graph
)
7154 /* Clear the implicit ref and address nodes from the successor
7156 for (i
= 1; i
< FIRST_REF_NODE
; i
++)
7158 if (graph
->succs
[i
])
7159 bitmap_clear_range (graph
->succs
[i
], FIRST_REF_NODE
,
7160 FIRST_REF_NODE
* 2);
7163 /* Free the successor list for the non-ref nodes. */
7164 for (i
= FIRST_REF_NODE
+ 1; i
< graph
->size
; i
++)
7166 if (graph
->succs
[i
])
7167 BITMAP_FREE (graph
->succs
[i
]);
7170 /* Now reallocate the size of the successor list as, and blow away
7171 the predecessor bitmaps. */
7172 graph
->size
= varmap
.length ();
7173 graph
->succs
= XRESIZEVEC (bitmap
, graph
->succs
, graph
->size
);
7175 free (graph
->implicit_preds
);
7176 graph
->implicit_preds
= NULL
;
7177 free (graph
->preds
);
7178 graph
->preds
= NULL
;
7179 bitmap_obstack_release (&predbitmap_obstack
);
7182 /* Solve the constraint set. */
7185 solve_constraints (void)
7187 struct scc_info
*si
;
7189 /* Sort varinfos so that ones that cannot be pointed to are last.
7190 This makes bitmaps more efficient. */
7191 unsigned int *map
= XNEWVEC (unsigned int, varmap
.length ());
7192 for (unsigned i
= 0; i
< integer_id
+ 1; ++i
)
7194 /* Start with non-register vars (as possibly address-taken), followed
7195 by register vars as conservative set of vars never appearing in
7196 the points-to solution bitmaps. */
7197 unsigned j
= integer_id
+ 1;
7198 for (unsigned i
= integer_id
+ 1; i
< varmap
.length (); ++i
)
7199 if (! varmap
[i
]->is_reg_var
)
7201 for (unsigned i
= integer_id
+ 1; i
< varmap
.length (); ++i
)
7202 if (varmap
[i
]->is_reg_var
)
7204 /* Shuffle varmap according to map. */
7205 for (unsigned i
= integer_id
+ 1; i
< varmap
.length (); ++i
)
7207 while (map
[varmap
[i
]->id
] != i
)
7208 std::swap (varmap
[i
], varmap
[map
[varmap
[i
]->id
]]);
7209 gcc_assert (bitmap_empty_p (varmap
[i
]->solution
));
7211 varmap
[i
]->next
= map
[varmap
[i
]->next
];
7212 varmap
[i
]->head
= map
[varmap
[i
]->head
];
7214 /* Finally rewrite constraints. */
7215 for (unsigned i
= 0; i
< constraints
.length (); ++i
)
7217 constraints
[i
]->lhs
.var
= map
[constraints
[i
]->lhs
.var
];
7218 constraints
[i
]->rhs
.var
= map
[constraints
[i
]->rhs
.var
];
7224 "\nCollapsing static cycles and doing variable "
7227 init_graph (varmap
.length () * 2);
7230 fprintf (dump_file
, "Building predecessor graph\n");
7231 build_pred_graph ();
7234 fprintf (dump_file
, "Detecting pointer and location "
7236 si
= perform_var_substitution (graph
);
7239 fprintf (dump_file
, "Rewriting constraints and unifying "
7241 rewrite_constraints (graph
, si
);
7243 build_succ_graph ();
7245 free_var_substitution_info (si
);
7247 /* Attach complex constraints to graph nodes. */
7248 move_complex_constraints (graph
);
7251 fprintf (dump_file
, "Uniting pointer but not location equivalent "
7253 unite_pointer_equivalences (graph
);
7256 fprintf (dump_file
, "Finding indirect cycles\n");
7257 find_indirect_cycles (graph
);
7259 /* Implicit nodes and predecessors are no longer necessary at this
7261 remove_preds_and_fake_succs (graph
);
7263 if (dump_file
&& (dump_flags
& TDF_GRAPH
))
7265 fprintf (dump_file
, "\n\n// The constraint graph before solve-graph "
7266 "in dot format:\n");
7267 dump_constraint_graph (dump_file
);
7268 fprintf (dump_file
, "\n\n");
7272 fprintf (dump_file
, "Solving graph\n");
7274 solve_graph (graph
);
7276 if (dump_file
&& (dump_flags
& TDF_GRAPH
))
7278 fprintf (dump_file
, "\n\n// The constraint graph after solve-graph "
7279 "in dot format:\n");
7280 dump_constraint_graph (dump_file
);
7281 fprintf (dump_file
, "\n\n");
7285 /* Create points-to sets for the current function. See the comments
7286 at the start of the file for an algorithmic overview. */
7289 compute_points_to_sets (void)
7294 timevar_push (TV_TREE_PTA
);
7298 intra_create_variable_infos (cfun
);
7300 /* Now walk all statements and build the constraint set. */
7301 FOR_EACH_BB_FN (bb
, cfun
)
7303 for (gphi_iterator gsi
= gsi_start_phis (bb
); !gsi_end_p (gsi
);
7306 gphi
*phi
= gsi
.phi ();
7308 if (! virtual_operand_p (gimple_phi_result (phi
)))
7309 find_func_aliases (cfun
, phi
);
7312 for (gimple_stmt_iterator gsi
= gsi_start_bb (bb
); !gsi_end_p (gsi
);
7315 gimple
*stmt
= gsi_stmt (gsi
);
7317 find_func_aliases (cfun
, stmt
);
7323 fprintf (dump_file
, "Points-to analysis\n\nConstraints:\n\n");
7324 dump_constraints (dump_file
, 0);
7327 /* From the constraints compute the points-to sets. */
7328 solve_constraints ();
7330 /* Post-process solutions for escapes through returns. */
7333 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
)
7334 if (greturn
*ret
= safe_dyn_cast
<greturn
*> (last_stmt (e
->src
)))
7336 tree val
= gimple_return_retval (ret
);
7337 /* ??? Easy to handle simple indirections with some work.
7338 Arbitrary references like foo.bar.baz are more difficult
7339 (but conservatively easy enough with just looking at the base).
7340 Mind to fixup find_func_aliases as well. */
7341 if (!val
|| !SSA_VAR_P (val
))
7343 /* returns happen last in non-IPA so they only influence
7344 the ESCAPED solution and we can filter local variables. */
7345 varinfo_t escaped_vi
= get_varinfo (find (escaped_id
));
7346 varinfo_t vi
= lookup_vi_for_tree (val
);
7347 bitmap delta
= BITMAP_ALLOC (&pta_obstack
);
7350 for (; vi
; vi
= vi_next (vi
))
7352 varinfo_t part_vi
= get_varinfo (find (vi
->id
));
7353 EXECUTE_IF_AND_COMPL_IN_BITMAP (part_vi
->solution
,
7354 escaped_vi
->solution
, 0, i
, bi
)
7356 varinfo_t pointed_to_vi
= get_varinfo (i
);
7357 if (pointed_to_vi
->is_global_var
7358 /* We delay marking of heap memory as global. */
7359 || pointed_to_vi
->is_heap_var
)
7360 bitmap_set_bit (delta
, i
);
7364 /* Now compute the transitive closure. */
7365 bitmap_ior_into (escaped_vi
->solution
, delta
);
7366 bitmap new_delta
= BITMAP_ALLOC (&pta_obstack
);
7367 while (!bitmap_empty_p (delta
))
7369 EXECUTE_IF_SET_IN_BITMAP (delta
, 0, i
, bi
)
7371 varinfo_t pointed_to_vi
= get_varinfo (i
);
7372 pointed_to_vi
= get_varinfo (find (pointed_to_vi
->id
));
7374 bitmap_iterator bi2
;
7375 EXECUTE_IF_AND_COMPL_IN_BITMAP (pointed_to_vi
->solution
,
7376 escaped_vi
->solution
,
7379 varinfo_t pointed_to_vi2
= get_varinfo (j
);
7380 if (pointed_to_vi2
->is_global_var
7381 /* We delay marking of heap memory as global. */
7382 || pointed_to_vi2
->is_heap_var
)
7383 bitmap_set_bit (new_delta
, j
);
7386 bitmap_ior_into (escaped_vi
->solution
, new_delta
);
7387 bitmap_clear (delta
);
7388 std::swap (delta
, new_delta
);
7390 BITMAP_FREE (delta
);
7391 BITMAP_FREE (new_delta
);
7395 dump_sa_points_to_info (dump_file
);
7397 /* Compute the points-to set for ESCAPED used for call-clobber analysis. */
7398 cfun
->gimple_df
->escaped
= find_what_var_points_to (cfun
->decl
,
7399 get_varinfo (escaped_id
));
7401 /* Make sure the ESCAPED solution (which is used as placeholder in
7402 other solutions) does not reference itself. This simplifies
7403 points-to solution queries. */
7404 cfun
->gimple_df
->escaped
.escaped
= 0;
7406 /* Compute the points-to sets for pointer SSA_NAMEs. */
7410 FOR_EACH_SSA_NAME (i
, ptr
, cfun
)
7412 if (POINTER_TYPE_P (TREE_TYPE (ptr
)))
7413 find_what_p_points_to (cfun
->decl
, ptr
);
7416 /* Compute the call-used/clobbered sets. */
7417 FOR_EACH_BB_FN (bb
, cfun
)
7419 gimple_stmt_iterator gsi
;
7421 for (gsi
= gsi_start_bb (bb
); !gsi_end_p (gsi
); gsi_next (&gsi
))
7424 struct pt_solution
*pt
;
7426 stmt
= dyn_cast
<gcall
*> (gsi_stmt (gsi
));
7430 pt
= gimple_call_use_set (stmt
);
7431 if (gimple_call_flags (stmt
) & ECF_CONST
)
7432 memset (pt
, 0, sizeof (struct pt_solution
));
7433 else if ((vi
= lookup_call_use_vi (stmt
)) != NULL
)
7435 *pt
= find_what_var_points_to (cfun
->decl
, vi
);
7436 /* Escaped (and thus nonlocal) variables are always
7437 implicitly used by calls. */
7438 /* ??? ESCAPED can be empty even though NONLOCAL
7445 /* If there is nothing special about this call then
7446 we have made everything that is used also escape. */
7447 *pt
= cfun
->gimple_df
->escaped
;
7451 pt
= gimple_call_clobber_set (stmt
);
7452 if (gimple_call_flags (stmt
) & (ECF_CONST
|ECF_PURE
|ECF_NOVOPS
))
7453 memset (pt
, 0, sizeof (struct pt_solution
));
7454 else if ((vi
= lookup_call_clobber_vi (stmt
)) != NULL
)
7456 *pt
= find_what_var_points_to (cfun
->decl
, vi
);
7457 /* Escaped (and thus nonlocal) variables are always
7458 implicitly clobbered by calls. */
7459 /* ??? ESCAPED can be empty even though NONLOCAL
7466 /* If there is nothing special about this call then
7467 we have made everything that is used also escape. */
7468 *pt
= cfun
->gimple_df
->escaped
;
7474 timevar_pop (TV_TREE_PTA
);
7478 /* Delete created points-to sets. */
7481 delete_points_to_sets (void)
7485 delete shared_bitmap_table
;
7486 shared_bitmap_table
= NULL
;
7487 if (dump_file
&& (dump_flags
& TDF_STATS
))
7488 fprintf (dump_file
, "Points to sets created:%d\n",
7489 stats
.points_to_sets_created
);
7492 delete call_stmt_vars
;
7493 bitmap_obstack_release (&pta_obstack
);
7494 constraints
.release ();
7496 for (i
= 0; i
< graph
->size
; i
++)
7497 graph
->complex[i
].release ();
7498 free (graph
->complex);
7501 free (graph
->succs
);
7503 free (graph
->pe_rep
);
7504 free (graph
->indirect_cycles
);
7508 variable_info_pool
.release ();
7509 constraint_pool
.release ();
7511 obstack_free (&fake_var_decl_obstack
, NULL
);
7513 delete final_solutions
;
7514 obstack_free (&final_solutions_obstack
, NULL
);
7519 unsigned short clique
;
7524 /* Mark "other" loads and stores as belonging to CLIQUE and with
7528 visit_loadstore (gimple
*, tree base
, tree ref
, void *data
)
7530 unsigned short clique
= ((vls_data
*) data
)->clique
;
7531 bitmap rvars
= ((vls_data
*) data
)->rvars
;
7532 bool escaped_p
= ((vls_data
*) data
)->escaped_p
;
7533 if (TREE_CODE (base
) == MEM_REF
7534 || TREE_CODE (base
) == TARGET_MEM_REF
)
7536 tree ptr
= TREE_OPERAND (base
, 0);
7537 if (TREE_CODE (ptr
) == SSA_NAME
)
7539 /* For parameters, get at the points-to set for the actual parm
7541 if (SSA_NAME_IS_DEFAULT_DEF (ptr
)
7542 && (TREE_CODE (SSA_NAME_VAR (ptr
)) == PARM_DECL
7543 || TREE_CODE (SSA_NAME_VAR (ptr
)) == RESULT_DECL
))
7544 ptr
= SSA_NAME_VAR (ptr
);
7546 /* We need to make sure 'ptr' doesn't include any of
7547 the restrict tags we added bases for in its points-to set. */
7548 varinfo_t vi
= lookup_vi_for_tree (ptr
);
7552 vi
= get_varinfo (find (vi
->id
));
7553 if (bitmap_intersect_p (rvars
, vi
->solution
)
7554 || (escaped_p
&& bitmap_bit_p (vi
->solution
, escaped_id
)))
7558 /* Do not overwrite existing cliques (that includes clique, base
7559 pairs we just set). */
7560 if (MR_DEPENDENCE_CLIQUE (base
) == 0)
7562 MR_DEPENDENCE_CLIQUE (base
) = clique
;
7563 MR_DEPENDENCE_BASE (base
) = 0;
7567 /* For plain decl accesses see whether they are accesses to globals
7568 and rewrite them to MEM_REFs with { clique, 0 }. */
7570 && is_global_var (base
)
7571 /* ??? We can't rewrite a plain decl with the walk_stmt_load_store
7576 while (handled_component_p (*basep
))
7577 basep
= &TREE_OPERAND (*basep
, 0);
7578 gcc_assert (VAR_P (*basep
));
7579 tree ptr
= build_fold_addr_expr (*basep
);
7580 tree zero
= build_int_cst (TREE_TYPE (ptr
), 0);
7581 *basep
= build2 (MEM_REF
, TREE_TYPE (*basep
), ptr
, zero
);
7582 MR_DEPENDENCE_CLIQUE (*basep
) = clique
;
7583 MR_DEPENDENCE_BASE (*basep
) = 0;
7591 unsigned short *clique
;
7592 unsigned short *last_ruid
;
7593 varinfo_t restrict_var
;
7596 /* If BASE is a MEM_REF then assign a clique, base pair to it, updating
7597 CLIQUE, *RESTRICT_VAR and LAST_RUID as passed via DATA.
7598 Return whether dependence info was assigned to BASE. */
7601 maybe_set_dependence_info (gimple
*, tree base
, tree
, void *data
)
7603 tree ptr
= ((msdi_data
*)data
)->ptr
;
7604 unsigned short &clique
= *((msdi_data
*)data
)->clique
;
7605 unsigned short &last_ruid
= *((msdi_data
*)data
)->last_ruid
;
7606 varinfo_t restrict_var
= ((msdi_data
*)data
)->restrict_var
;
7607 if ((TREE_CODE (base
) == MEM_REF
7608 || TREE_CODE (base
) == TARGET_MEM_REF
)
7609 && TREE_OPERAND (base
, 0) == ptr
)
7611 /* Do not overwrite existing cliques. This avoids overwriting dependence
7612 info inlined from a function with restrict parameters inlined
7613 into a function with restrict parameters. This usually means we
7614 prefer to be precise in innermost loops. */
7615 if (MR_DEPENDENCE_CLIQUE (base
) == 0)
7619 if (cfun
->last_clique
== 0)
7620 cfun
->last_clique
= 1;
7623 if (restrict_var
->ruid
== 0)
7624 restrict_var
->ruid
= ++last_ruid
;
7625 MR_DEPENDENCE_CLIQUE (base
) = clique
;
7626 MR_DEPENDENCE_BASE (base
) = restrict_var
->ruid
;
7633 /* Clear dependence info for the clique DATA. */
7636 clear_dependence_clique (gimple
*, tree base
, tree
, void *data
)
7638 unsigned short clique
= (uintptr_t)data
;
7639 if ((TREE_CODE (base
) == MEM_REF
7640 || TREE_CODE (base
) == TARGET_MEM_REF
)
7641 && MR_DEPENDENCE_CLIQUE (base
) == clique
)
7643 MR_DEPENDENCE_CLIQUE (base
) = 0;
7644 MR_DEPENDENCE_BASE (base
) = 0;
7650 /* Compute the set of independend memory references based on restrict
7651 tags and their conservative propagation to the points-to sets. */
7654 compute_dependence_clique (void)
7656 /* First clear the special "local" clique. */
7658 if (cfun
->last_clique
!= 0)
7659 FOR_EACH_BB_FN (bb
, cfun
)
7660 for (gimple_stmt_iterator gsi
= gsi_start_bb (bb
);
7661 !gsi_end_p (gsi
); gsi_next (&gsi
))
7663 gimple
*stmt
= gsi_stmt (gsi
);
7664 walk_stmt_load_store_ops (stmt
, (void *)(uintptr_t) 1,
7665 clear_dependence_clique
,
7666 clear_dependence_clique
);
7669 unsigned short clique
= 0;
7670 unsigned short last_ruid
= 0;
7671 bitmap rvars
= BITMAP_ALLOC (NULL
);
7672 bool escaped_p
= false;
7673 for (unsigned i
= 0; i
< num_ssa_names
; ++i
)
7675 tree ptr
= ssa_name (i
);
7676 if (!ptr
|| !POINTER_TYPE_P (TREE_TYPE (ptr
)))
7679 /* Avoid all this when ptr is not dereferenced? */
7681 if (SSA_NAME_IS_DEFAULT_DEF (ptr
)
7682 && (TREE_CODE (SSA_NAME_VAR (ptr
)) == PARM_DECL
7683 || TREE_CODE (SSA_NAME_VAR (ptr
)) == RESULT_DECL
))
7684 p
= SSA_NAME_VAR (ptr
);
7685 varinfo_t vi
= lookup_vi_for_tree (p
);
7688 vi
= get_varinfo (find (vi
->id
));
7691 varinfo_t restrict_var
= NULL
;
7692 EXECUTE_IF_SET_IN_BITMAP (vi
->solution
, 0, j
, bi
)
7694 varinfo_t oi
= get_varinfo (j
);
7696 oi
= get_varinfo (oi
->head
);
7697 if (oi
->is_restrict_var
)
7700 && restrict_var
!= oi
)
7702 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
7704 fprintf (dump_file
, "found restrict pointed-to "
7706 print_generic_expr (dump_file
, ptr
);
7707 fprintf (dump_file
, " but not exclusively\n");
7709 restrict_var
= NULL
;
7714 /* NULL is the only other valid points-to entry. */
7715 else if (oi
->id
!= nothing_id
)
7717 restrict_var
= NULL
;
7721 /* Ok, found that ptr must(!) point to a single(!) restrict
7723 /* ??? PTA isn't really a proper propagation engine to compute
7725 ??? We could handle merging of two restricts by unifying them. */
7728 /* Now look at possible dereferences of ptr. */
7729 imm_use_iterator ui
;
7732 msdi_data data
= { ptr
, &clique
, &last_ruid
, restrict_var
};
7733 FOR_EACH_IMM_USE_STMT (use_stmt
, ui
, ptr
)
7734 used
|= walk_stmt_load_store_ops (use_stmt
, &data
,
7735 maybe_set_dependence_info
,
7736 maybe_set_dependence_info
);
7739 /* Add all subvars to the set of restrict pointed-to set. */
7740 for (unsigned sv
= restrict_var
->head
; sv
!= 0;
7741 sv
= get_varinfo (sv
)->next
)
7742 bitmap_set_bit (rvars
, sv
);
7743 varinfo_t escaped
= get_varinfo (find (escaped_id
));
7744 if (bitmap_bit_p (escaped
->solution
, restrict_var
->id
))
7752 /* Assign the BASE id zero to all accesses not based on a restrict
7753 pointer. That way they get disambiguated against restrict
7754 accesses but not against each other. */
7755 /* ??? For restricts derived from globals (thus not incoming
7756 parameters) we can't restrict scoping properly thus the following
7757 is too aggressive there. For now we have excluded those globals from
7758 getting into the MR_DEPENDENCE machinery. */
7759 vls_data data
= { clique
, escaped_p
, rvars
};
7761 FOR_EACH_BB_FN (bb
, cfun
)
7762 for (gimple_stmt_iterator gsi
= gsi_start_bb (bb
);
7763 !gsi_end_p (gsi
); gsi_next (&gsi
))
7765 gimple
*stmt
= gsi_stmt (gsi
);
7766 walk_stmt_load_store_ops (stmt
, &data
,
7767 visit_loadstore
, visit_loadstore
);
7771 BITMAP_FREE (rvars
);
7774 /* Compute points-to information for every SSA_NAME pointer in the
7775 current function and compute the transitive closure of escaped
7776 variables to re-initialize the call-clobber states of local variables. */
7779 compute_may_aliases (void)
7781 if (cfun
->gimple_df
->ipa_pta
)
7785 fprintf (dump_file
, "\nNot re-computing points-to information "
7786 "because IPA points-to information is available.\n\n");
7788 /* But still dump what we have remaining it. */
7789 dump_alias_info (dump_file
);
7795 /* For each pointer P_i, determine the sets of variables that P_i may
7796 point-to. Compute the reachability set of escaped and call-used
7798 compute_points_to_sets ();
7800 /* Debugging dumps. */
7802 dump_alias_info (dump_file
);
7804 /* Compute restrict-based memory disambiguations. */
7805 compute_dependence_clique ();
7807 /* Deallocate memory used by aliasing data structures and the internal
7808 points-to solution. */
7809 delete_points_to_sets ();
7811 gcc_assert (!need_ssa_update_p (cfun
));
7816 /* A dummy pass to cause points-to information to be computed via
7817 TODO_rebuild_alias. */
7821 const pass_data pass_data_build_alias
=
7823 GIMPLE_PASS
, /* type */
7825 OPTGROUP_NONE
, /* optinfo_flags */
7826 TV_NONE
, /* tv_id */
7827 ( PROP_cfg
| PROP_ssa
), /* properties_required */
7828 0, /* properties_provided */
7829 0, /* properties_destroyed */
7830 0, /* todo_flags_start */
7831 TODO_rebuild_alias
, /* todo_flags_finish */
7834 class pass_build_alias
: public gimple_opt_pass
7837 pass_build_alias (gcc::context
*ctxt
)
7838 : gimple_opt_pass (pass_data_build_alias
, ctxt
)
7841 /* opt_pass methods: */
7842 virtual bool gate (function
*) { return flag_tree_pta
; }
7844 }; // class pass_build_alias
7849 make_pass_build_alias (gcc::context
*ctxt
)
7851 return new pass_build_alias (ctxt
);
7854 /* A dummy pass to cause points-to information to be computed via
7855 TODO_rebuild_alias. */
7859 const pass_data pass_data_build_ealias
=
7861 GIMPLE_PASS
, /* type */
7862 "ealias", /* name */
7863 OPTGROUP_NONE
, /* optinfo_flags */
7864 TV_NONE
, /* tv_id */
7865 ( PROP_cfg
| PROP_ssa
), /* properties_required */
7866 0, /* properties_provided */
7867 0, /* properties_destroyed */
7868 0, /* todo_flags_start */
7869 TODO_rebuild_alias
, /* todo_flags_finish */
7872 class pass_build_ealias
: public gimple_opt_pass
7875 pass_build_ealias (gcc::context
*ctxt
)
7876 : gimple_opt_pass (pass_data_build_ealias
, ctxt
)
7879 /* opt_pass methods: */
7880 virtual bool gate (function
*) { return flag_tree_pta
; }
7882 }; // class pass_build_ealias
7887 make_pass_build_ealias (gcc::context
*ctxt
)
7889 return new pass_build_ealias (ctxt
);
7893 /* IPA PTA solutions for ESCAPED. */
7894 struct pt_solution ipa_escaped_pt
7895 = { true, false, false, false, false,
7896 false, false, false, false, false, NULL
};
7898 /* Associate node with varinfo DATA. Worker for
7899 cgraph_for_symbol_thunks_and_aliases. */
7901 associate_varinfo_to_alias (struct cgraph_node
*node
, void *data
)
7904 || (node
->thunk
.thunk_p
7905 && ! node
->global
.inlined_to
))
7907 && !node
->ifunc_resolver
)
7908 insert_vi_for_tree (node
->decl
, (varinfo_t
)data
);
7912 /* Dump varinfo VI to FILE. */
7915 dump_varinfo (FILE *file
, varinfo_t vi
)
7920 fprintf (file
, "%u: %s\n", vi
->id
, vi
->name
);
7922 const char *sep
= " ";
7923 if (vi
->is_artificial_var
)
7924 fprintf (file
, "%sartificial", sep
);
7925 if (vi
->is_special_var
)
7926 fprintf (file
, "%sspecial", sep
);
7927 if (vi
->is_unknown_size_var
)
7928 fprintf (file
, "%sunknown-size", sep
);
7929 if (vi
->is_full_var
)
7930 fprintf (file
, "%sfull", sep
);
7931 if (vi
->is_heap_var
)
7932 fprintf (file
, "%sheap", sep
);
7933 if (vi
->may_have_pointers
)
7934 fprintf (file
, "%smay-have-pointers", sep
);
7935 if (vi
->only_restrict_pointers
)
7936 fprintf (file
, "%sonly-restrict-pointers", sep
);
7937 if (vi
->is_restrict_var
)
7938 fprintf (file
, "%sis-restrict-var", sep
);
7939 if (vi
->is_global_var
)
7940 fprintf (file
, "%sglobal", sep
);
7941 if (vi
->is_ipa_escape_point
)
7942 fprintf (file
, "%sipa-escape-point", sep
);
7944 fprintf (file
, "%sfn-info", sep
);
7946 fprintf (file
, "%srestrict-uid:%u", sep
, vi
->ruid
);
7948 fprintf (file
, "%snext:%u", sep
, vi
->next
);
7949 if (vi
->head
!= vi
->id
)
7950 fprintf (file
, "%shead:%u", sep
, vi
->head
);
7952 fprintf (file
, "%soffset:" HOST_WIDE_INT_PRINT_DEC
, sep
, vi
->offset
);
7953 if (vi
->size
!= ~(unsigned HOST_WIDE_INT
)0)
7954 fprintf (file
, "%ssize:" HOST_WIDE_INT_PRINT_DEC
, sep
, vi
->size
);
7955 if (vi
->fullsize
!= ~(unsigned HOST_WIDE_INT
)0
7956 && vi
->fullsize
!= vi
->size
)
7957 fprintf (file
, "%sfullsize:" HOST_WIDE_INT_PRINT_DEC
, sep
,
7959 fprintf (file
, "\n");
7961 if (vi
->solution
&& !bitmap_empty_p (vi
->solution
))
7965 fprintf (file
, " solution: {");
7966 EXECUTE_IF_SET_IN_BITMAP (vi
->solution
, 0, i
, bi
)
7967 fprintf (file
, " %u", i
);
7968 fprintf (file
, " }\n");
7971 if (vi
->oldsolution
&& !bitmap_empty_p (vi
->oldsolution
)
7972 && !bitmap_equal_p (vi
->solution
, vi
->oldsolution
))
7976 fprintf (file
, " oldsolution: {");
7977 EXECUTE_IF_SET_IN_BITMAP (vi
->oldsolution
, 0, i
, bi
)
7978 fprintf (file
, " %u", i
);
7979 fprintf (file
, " }\n");
7983 /* Dump varinfo VI to stderr. */
7986 debug_varinfo (varinfo_t vi
)
7988 dump_varinfo (stderr
, vi
);
7991 /* Dump varmap to FILE. */
7994 dump_varmap (FILE *file
)
7996 if (varmap
.length () == 0)
7999 fprintf (file
, "variables:\n");
8001 for (unsigned int i
= 0; i
< varmap
.length (); ++i
)
8003 varinfo_t vi
= get_varinfo (i
);
8004 dump_varinfo (file
, vi
);
8007 fprintf (file
, "\n");
8010 /* Dump varmap to stderr. */
8015 dump_varmap (stderr
);
8018 /* Compute whether node is refered to non-locally. Worker for
8019 cgraph_for_symbol_thunks_and_aliases. */
8021 refered_from_nonlocal_fn (struct cgraph_node
*node
, void *data
)
8023 bool *nonlocal_p
= (bool *)data
;
8024 *nonlocal_p
|= (node
->used_from_other_partition
8025 || node
->externally_visible
8026 || node
->force_output
8027 || lookup_attribute ("noipa", DECL_ATTRIBUTES (node
->decl
)));
8031 /* Same for varpool nodes. */
8033 refered_from_nonlocal_var (struct varpool_node
*node
, void *data
)
8035 bool *nonlocal_p
= (bool *)data
;
8036 *nonlocal_p
|= (node
->used_from_other_partition
8037 || node
->externally_visible
8038 || node
->force_output
);
8042 /* Execute the driver for IPA PTA. */
8044 ipa_pta_execute (void)
8046 struct cgraph_node
*node
;
8048 unsigned int from
= 0;
8054 if (dump_file
&& (dump_flags
& TDF_DETAILS
))
8056 symtab
->dump (dump_file
);
8057 fprintf (dump_file
, "\n");
8062 fprintf (dump_file
, "Generating generic constraints\n\n");
8063 dump_constraints (dump_file
, from
);
8064 fprintf (dump_file
, "\n");
8065 from
= constraints
.length ();
8068 /* Build the constraints. */
8069 FOR_EACH_DEFINED_FUNCTION (node
)
8072 /* Nodes without a body are not interesting. Especially do not
8073 visit clones at this point for now - we get duplicate decls
8074 there for inline clones at least. */
8075 if (!node
->has_gimple_body_p () || node
->global
.inlined_to
)
8079 gcc_assert (!node
->clone_of
);
8081 /* For externally visible or attribute used annotated functions use
8082 local constraints for their arguments.
8083 For local functions we see all callers and thus do not need initial
8084 constraints for parameters. */
8085 bool nonlocal_p
= (node
->used_from_other_partition
8086 || node
->externally_visible
8087 || node
->force_output
8088 || lookup_attribute ("noipa",
8089 DECL_ATTRIBUTES (node
->decl
)));
8090 node
->call_for_symbol_thunks_and_aliases (refered_from_nonlocal_fn
,
8093 vi
= create_function_info_for (node
->decl
,
8094 alias_get_name (node
->decl
), false,
8097 && from
!= constraints
.length ())
8100 "Generating intial constraints for %s", node
->name ());
8101 if (DECL_ASSEMBLER_NAME_SET_P (node
->decl
))
8102 fprintf (dump_file
, " (%s)",
8104 (DECL_ASSEMBLER_NAME (node
->decl
)));
8105 fprintf (dump_file
, "\n\n");
8106 dump_constraints (dump_file
, from
);
8107 fprintf (dump_file
, "\n");
8109 from
= constraints
.length ();
8112 node
->call_for_symbol_thunks_and_aliases
8113 (associate_varinfo_to_alias
, vi
, true);
8116 /* Create constraints for global variables and their initializers. */
8117 FOR_EACH_VARIABLE (var
)
8119 if (var
->alias
&& var
->analyzed
)
8122 varinfo_t vi
= get_vi_for_tree (var
->decl
);
8124 /* For the purpose of IPA PTA unit-local globals are not
8126 bool nonlocal_p
= (var
->used_from_other_partition
8127 || var
->externally_visible
8128 || var
->force_output
);
8129 var
->call_for_symbol_and_aliases (refered_from_nonlocal_var
,
8132 vi
->is_ipa_escape_point
= true;
8136 && from
!= constraints
.length ())
8139 "Generating constraints for global initializers\n\n");
8140 dump_constraints (dump_file
, from
);
8141 fprintf (dump_file
, "\n");
8142 from
= constraints
.length ();
8145 FOR_EACH_DEFINED_FUNCTION (node
)
8147 struct function
*func
;
8150 /* Nodes without a body are not interesting. */
8151 if (!node
->has_gimple_body_p () || node
->clone_of
)
8157 "Generating constraints for %s", node
->name ());
8158 if (DECL_ASSEMBLER_NAME_SET_P (node
->decl
))
8159 fprintf (dump_file
, " (%s)",
8161 (DECL_ASSEMBLER_NAME (node
->decl
)));
8162 fprintf (dump_file
, "\n");
8165 func
= DECL_STRUCT_FUNCTION (node
->decl
);
8166 gcc_assert (cfun
== NULL
);
8168 /* Build constriants for the function body. */
8169 FOR_EACH_BB_FN (bb
, func
)
8171 for (gphi_iterator gsi
= gsi_start_phis (bb
); !gsi_end_p (gsi
);
8174 gphi
*phi
= gsi
.phi ();
8176 if (! virtual_operand_p (gimple_phi_result (phi
)))
8177 find_func_aliases (func
, phi
);
8180 for (gimple_stmt_iterator gsi
= gsi_start_bb (bb
); !gsi_end_p (gsi
);
8183 gimple
*stmt
= gsi_stmt (gsi
);
8185 find_func_aliases (func
, stmt
);
8186 find_func_clobbers (func
, stmt
);
8192 fprintf (dump_file
, "\n");
8193 dump_constraints (dump_file
, from
);
8194 fprintf (dump_file
, "\n");
8195 from
= constraints
.length ();
8199 /* From the constraints compute the points-to sets. */
8200 solve_constraints ();
8203 dump_sa_points_to_info (dump_file
);
8205 /* Now post-process solutions to handle locals from different
8206 runtime instantiations coming in through recursive invocations. */
8207 unsigned shadow_var_cnt
= 0;
8208 for (unsigned i
= 1; i
< varmap
.length (); ++i
)
8210 varinfo_t fi
= get_varinfo (i
);
8213 /* Automatic variables pointed to by their containing functions
8214 parameters need this treatment. */
8215 for (varinfo_t ai
= first_vi_for_offset (fi
, fi_parm_base
);
8216 ai
; ai
= vi_next (ai
))
8218 varinfo_t vi
= get_varinfo (find (ai
->id
));
8221 EXECUTE_IF_SET_IN_BITMAP (vi
->solution
, 0, j
, bi
)
8223 varinfo_t pt
= get_varinfo (j
);
8224 if (pt
->shadow_var_uid
== 0
8226 && auto_var_in_fn_p (pt
->decl
, fi
->decl
))
8228 pt
->shadow_var_uid
= allocate_decl_uid ();
8233 /* As well as global variables which are another way of passing
8234 arguments to recursive invocations. */
8235 else if (fi
->is_global_var
)
8237 for (varinfo_t ai
= fi
; ai
; ai
= vi_next (ai
))
8239 varinfo_t vi
= get_varinfo (find (ai
->id
));
8242 EXECUTE_IF_SET_IN_BITMAP (vi
->solution
, 0, j
, bi
)
8244 varinfo_t pt
= get_varinfo (j
);
8245 if (pt
->shadow_var_uid
== 0
8247 && auto_var_p (pt
->decl
))
8249 pt
->shadow_var_uid
= allocate_decl_uid ();
8256 if (shadow_var_cnt
&& dump_file
&& (dump_flags
& TDF_DETAILS
))
8257 fprintf (dump_file
, "Allocated %u shadow variables for locals "
8258 "maybe leaking into recursive invocations of their containing "
8259 "functions\n", shadow_var_cnt
);
8261 /* Compute the global points-to sets for ESCAPED.
8262 ??? Note that the computed escape set is not correct
8263 for the whole unit as we fail to consider graph edges to
8264 externally visible functions. */
8265 ipa_escaped_pt
= find_what_var_points_to (NULL
, get_varinfo (escaped_id
));
8267 /* Make sure the ESCAPED solution (which is used as placeholder in
8268 other solutions) does not reference itself. This simplifies
8269 points-to solution queries. */
8270 ipa_escaped_pt
.ipa_escaped
= 0;
8272 /* Assign the points-to sets to the SSA names in the unit. */
8273 FOR_EACH_DEFINED_FUNCTION (node
)
8276 struct function
*fn
;
8280 /* Nodes without a body are not interesting. */
8281 if (!node
->has_gimple_body_p () || node
->clone_of
)
8284 fn
= DECL_STRUCT_FUNCTION (node
->decl
);
8286 /* Compute the points-to sets for pointer SSA_NAMEs. */
8287 FOR_EACH_VEC_ELT (*fn
->gimple_df
->ssa_names
, i
, ptr
)
8290 && POINTER_TYPE_P (TREE_TYPE (ptr
)))
8291 find_what_p_points_to (node
->decl
, ptr
);
8294 /* Compute the call-use and call-clobber sets for indirect calls
8295 and calls to external functions. */
8296 FOR_EACH_BB_FN (bb
, fn
)
8298 gimple_stmt_iterator gsi
;
8300 for (gsi
= gsi_start_bb (bb
); !gsi_end_p (gsi
); gsi_next (&gsi
))
8303 struct pt_solution
*pt
;
8307 stmt
= dyn_cast
<gcall
*> (gsi_stmt (gsi
));
8311 /* Handle direct calls to functions with body. */
8312 decl
= gimple_call_fndecl (stmt
);
8315 tree called_decl
= NULL_TREE
;
8316 if (gimple_call_builtin_p (stmt
, BUILT_IN_GOMP_PARALLEL
))
8317 called_decl
= TREE_OPERAND (gimple_call_arg (stmt
, 0), 0);
8318 else if (gimple_call_builtin_p (stmt
, BUILT_IN_GOACC_PARALLEL
))
8319 called_decl
= TREE_OPERAND (gimple_call_arg (stmt
, 1), 0);
8321 if (called_decl
!= NULL_TREE
8322 && !fndecl_maybe_in_other_partition (called_decl
))
8327 && (fi
= lookup_vi_for_tree (decl
))
8330 *gimple_call_clobber_set (stmt
)
8331 = find_what_var_points_to
8332 (node
->decl
, first_vi_for_offset (fi
, fi_clobbers
));
8333 *gimple_call_use_set (stmt
)
8334 = find_what_var_points_to
8335 (node
->decl
, first_vi_for_offset (fi
, fi_uses
));
8337 /* Handle direct calls to external functions. */
8338 else if (decl
&& (!fi
|| fi
->decl
))
8340 pt
= gimple_call_use_set (stmt
);
8341 if (gimple_call_flags (stmt
) & ECF_CONST
)
8342 memset (pt
, 0, sizeof (struct pt_solution
));
8343 else if ((vi
= lookup_call_use_vi (stmt
)) != NULL
)
8345 *pt
= find_what_var_points_to (node
->decl
, vi
);
8346 /* Escaped (and thus nonlocal) variables are always
8347 implicitly used by calls. */
8348 /* ??? ESCAPED can be empty even though NONLOCAL
8351 pt
->ipa_escaped
= 1;
8355 /* If there is nothing special about this call then
8356 we have made everything that is used also escape. */
8357 *pt
= ipa_escaped_pt
;
8361 pt
= gimple_call_clobber_set (stmt
);
8362 if (gimple_call_flags (stmt
) & (ECF_CONST
|ECF_PURE
|ECF_NOVOPS
))
8363 memset (pt
, 0, sizeof (struct pt_solution
));
8364 else if ((vi
= lookup_call_clobber_vi (stmt
)) != NULL
)
8366 *pt
= find_what_var_points_to (node
->decl
, vi
);
8367 /* Escaped (and thus nonlocal) variables are always
8368 implicitly clobbered by calls. */
8369 /* ??? ESCAPED can be empty even though NONLOCAL
8372 pt
->ipa_escaped
= 1;
8376 /* If there is nothing special about this call then
8377 we have made everything that is used also escape. */
8378 *pt
= ipa_escaped_pt
;
8382 /* Handle indirect calls. */
8383 else if ((fi
= get_fi_for_callee (stmt
)))
8385 /* We need to accumulate all clobbers/uses of all possible
8387 fi
= get_varinfo (find (fi
->id
));
8388 /* If we cannot constrain the set of functions we'll end up
8389 calling we end up using/clobbering everything. */
8390 if (bitmap_bit_p (fi
->solution
, anything_id
)
8391 || bitmap_bit_p (fi
->solution
, nonlocal_id
)
8392 || bitmap_bit_p (fi
->solution
, escaped_id
))
8394 pt_solution_reset (gimple_call_clobber_set (stmt
));
8395 pt_solution_reset (gimple_call_use_set (stmt
));
8401 struct pt_solution
*uses
, *clobbers
;
8403 uses
= gimple_call_use_set (stmt
);
8404 clobbers
= gimple_call_clobber_set (stmt
);
8405 memset (uses
, 0, sizeof (struct pt_solution
));
8406 memset (clobbers
, 0, sizeof (struct pt_solution
));
8407 EXECUTE_IF_SET_IN_BITMAP (fi
->solution
, 0, i
, bi
)
8409 struct pt_solution sol
;
8411 vi
= get_varinfo (i
);
8412 if (!vi
->is_fn_info
)
8414 /* ??? We could be more precise here? */
8416 uses
->ipa_escaped
= 1;
8417 clobbers
->nonlocal
= 1;
8418 clobbers
->ipa_escaped
= 1;
8422 if (!uses
->anything
)
8424 sol
= find_what_var_points_to
8426 first_vi_for_offset (vi
, fi_uses
));
8427 pt_solution_ior_into (uses
, &sol
);
8429 if (!clobbers
->anything
)
8431 sol
= find_what_var_points_to
8433 first_vi_for_offset (vi
, fi_clobbers
));
8434 pt_solution_ior_into (clobbers
, &sol
);
8444 fn
->gimple_df
->ipa_pta
= true;
8446 /* We have to re-set the final-solution cache after each function
8447 because what is a "global" is dependent on function context. */
8448 final_solutions
->empty ();
8449 obstack_free (&final_solutions_obstack
, NULL
);
8450 gcc_obstack_init (&final_solutions_obstack
);
8453 delete_points_to_sets ();
8462 const pass_data pass_data_ipa_pta
=
8464 SIMPLE_IPA_PASS
, /* type */
8466 OPTGROUP_NONE
, /* optinfo_flags */
8467 TV_IPA_PTA
, /* tv_id */
8468 0, /* properties_required */
8469 0, /* properties_provided */
8470 0, /* properties_destroyed */
8471 0, /* todo_flags_start */
8472 0, /* todo_flags_finish */
8475 class pass_ipa_pta
: public simple_ipa_opt_pass
8478 pass_ipa_pta (gcc::context
*ctxt
)
8479 : simple_ipa_opt_pass (pass_data_ipa_pta
, ctxt
)
8482 /* opt_pass methods: */
8483 virtual bool gate (function
*)
8487 /* Don't bother doing anything if the program has errors. */
8491 opt_pass
* clone () { return new pass_ipa_pta (m_ctxt
); }
8493 virtual unsigned int execute (function
*) { return ipa_pta_execute (); }
8495 }; // class pass_ipa_pta
8499 simple_ipa_opt_pass
*
8500 make_pass_ipa_pta (gcc::context
*ctxt
)
8502 return new pass_ipa_pta (ctxt
);