1 /* Tree SCC value numbering
2 Copyright (C) 2007-2015 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/>. */
21 #ifndef TREE_SSA_SCCVN_H
22 #define TREE_SSA_SCCVN_H
24 /* In tree-ssa-sccvn.c */
25 bool expressions_equal_p (tree
, tree
);
28 /* TOP of the VN lattice. */
31 /* N-ary operations in the hashtable consist of length operands, an
32 opcode, and a type. Result is the value number of the operation,
33 and hashcode is stored to avoid having to calculate it
36 typedef struct vn_nary_op_s
38 /* Unique identify that all expressions with the same value have. */
39 unsigned int value_id
;
40 ENUM_BITFIELD(tree_code
) opcode
: 16;
47 typedef const struct vn_nary_op_s
*const_vn_nary_op_t
;
49 /* Return the size of a vn_nary_op_t with LENGTH operands. */
52 sizeof_vn_nary_op (unsigned int length
)
54 return sizeof (struct vn_nary_op_s
) + sizeof (tree
) * length
- sizeof (tree
);
57 /* Phi nodes in the hashtable consist of their non-VN_TOP phi
58 arguments, and the basic block the phi is in. Result is the value
59 number of the operation, and hashcode is stored to avoid having to
60 calculate it repeatedly. Phi nodes not in the same block are never
61 considered equivalent. */
63 typedef struct vn_phi_s
65 /* Unique identifier that all expressions with the same value have. */
66 unsigned int value_id
;
73 typedef const struct vn_phi_s
*const_vn_phi_t
;
75 /* Reference operands only exist in reference operations structures.
76 They consist of an opcode, type, and some number of operands. For
77 a given opcode, some, all, or none of the operands may be used.
78 The operands are there to store the information that makes up the
79 portion of the addressing calculation that opcode performs. */
81 typedef struct vn_reference_op_struct
83 ENUM_BITFIELD(tree_code
) opcode
: 16;
84 /* 1 for instrumented calls. */
85 unsigned with_bounds
: 1;
86 /* Dependence info, used for [TARGET_]MEM_REF only. */
87 unsigned short clique
;
89 /* Constant offset this op adds or -1 if it is variable. */
97 typedef vn_reference_op_s
*vn_reference_op_t
;
98 typedef const vn_reference_op_s
*const_vn_reference_op_t
;
101 /* A reference operation in the hashtable is representation as
102 the vuse, representing the memory state at the time of
103 the operation, and a collection of operands that make up the
104 addressing calculation. If two vn_reference_t's have the same set
105 of operands, they access the same memory location. We also store
106 the resulting value number, and the hashcode. */
108 typedef struct vn_reference_s
110 /* Unique identifier that all expressions with the same value have. */
111 unsigned int value_id
;
116 vec
<vn_reference_op_s
> operands
;
120 typedef const struct vn_reference_s
*const_vn_reference_t
;
122 typedef struct vn_constant_s
124 unsigned int value_id
;
129 enum vn_kind
{ VN_NONE
, VN_CONSTANT
, VN_NARY
, VN_REFERENCE
, VN_PHI
};
130 enum vn_kind
vn_get_stmt_kind (gimple
*);
132 /* Hash the type TYPE using bits that distinguishes it in the
133 types_compatible_p sense. */
135 static inline hashval_t
136 vn_hash_type (tree type
)
138 return (INTEGRAL_TYPE_P (type
)
139 + (INTEGRAL_TYPE_P (type
)
140 ? TYPE_PRECISION (type
) + TYPE_UNSIGNED (type
) : 0));
143 /* Hash the constant CONSTANT with distinguishing type incompatible
144 constants in the types_compatible_p sense. */
146 static inline hashval_t
147 vn_hash_constant_with_type (tree constant
)
149 inchash::hash hstate
;
150 inchash::add_expr (constant
, hstate
);
151 hstate
.merge_hash (vn_hash_type (TREE_TYPE (constant
)));
152 return hstate
.end ();
155 /* Compare the constants C1 and C2 with distinguishing type incompatible
156 constants in the types_compatible_p sense. */
159 vn_constant_eq_with_type (tree c1
, tree c2
)
161 return (expressions_equal_p (c1
, c2
)
162 && types_compatible_p (TREE_TYPE (c1
), TREE_TYPE (c2
)));
165 typedef struct vn_ssa_aux
167 /* Value number. This may be an SSA name or a constant. */
169 /* Statements to insert if needs_insertion is true. */
172 /* Unique identifier that all expressions with the same value have. */
173 unsigned int value_id
;
175 /* SCC information. */
178 unsigned visited
: 1;
179 unsigned on_sccstack
: 1;
181 /* Whether the SSA_NAME has been value numbered already. This is
182 only saying whether visit_use has been called on it at least
183 once. It cannot be used to avoid visitation for SSA_NAME's
184 involved in non-singleton SCC's. */
185 unsigned use_processed
: 1;
187 /* Whether the SSA_NAME has no defining statement and thus an
188 insertion of such with EXPR as definition is required before
189 a use can be created of it. */
190 unsigned needs_insertion
: 1;
193 enum vn_lookup_kind
{ VN_NOWALK
, VN_WALK
, VN_WALKREWRITE
};
195 /* Return the value numbering info for an SSA_NAME. */
196 extern vn_ssa_aux_t
VN_INFO (tree
);
197 extern vn_ssa_aux_t
VN_INFO_GET (tree
);
198 tree
vn_get_expr_for (tree
);
199 bool run_scc_vn (vn_lookup_kind
);
200 void free_scc_vn (void);
201 tree
vn_nary_op_lookup (tree
, vn_nary_op_t
*);
202 tree
vn_nary_op_lookup_stmt (gimple
*, vn_nary_op_t
*);
203 tree
vn_nary_op_lookup_pieces (unsigned int, enum tree_code
,
204 tree
, tree
*, vn_nary_op_t
*);
205 vn_nary_op_t
vn_nary_op_insert (tree
, tree
);
206 vn_nary_op_t
vn_nary_op_insert_pieces (unsigned int, enum tree_code
,
207 tree
, tree
*, tree
, unsigned int);
208 bool ao_ref_init_from_vn_reference (ao_ref
*, alias_set_type
, tree
,
209 vec
<vn_reference_op_s
> );
210 tree
vn_reference_lookup_pieces (tree
, alias_set_type
, tree
,
211 vec
<vn_reference_op_s
> ,
212 vn_reference_t
*, vn_lookup_kind
);
213 tree
vn_reference_lookup (tree
, tree
, vn_lookup_kind
, vn_reference_t
*);
214 void vn_reference_lookup_call (gcall
*, vn_reference_t
*, vn_reference_t
);
215 vn_reference_t
vn_reference_insert_pieces (tree
, alias_set_type
, tree
,
216 vec
<vn_reference_op_s
> ,
219 bool vn_nary_op_eq (const_vn_nary_op_t
const vno1
,
220 const_vn_nary_op_t
const vno2
);
221 bool vn_nary_may_trap (vn_nary_op_t
);
222 bool vn_reference_eq (const_vn_reference_t
const, const_vn_reference_t
const);
223 unsigned int get_max_value_id (void);
224 unsigned int get_next_value_id (void);
225 unsigned int get_constant_value_id (tree
);
226 unsigned int get_or_alloc_constant_value_id (tree
);
227 bool value_id_constant_p (unsigned int);
228 tree
fully_constant_vn_reference_p (vn_reference_t
);
230 /* Valueize NAME if it is an SSA name, otherwise just return it. */
233 vn_valueize (tree name
)
235 if (TREE_CODE (name
) == SSA_NAME
)
237 tree tem
= VN_INFO (name
)->valnum
;
238 return tem
== VN_TOP
? name
: tem
;
243 #endif /* TREE_SSA_SCCVN_H */