1 | /* Tree SCC value numbering |
---|---|

2 | Copyright (C) 2007-2017 Free Software Foundation, Inc. |

3 | Contributed by Daniel Berlin <dberlin@dberlin.org> |

4 | |

5 | This file is part of GCC. |

6 | |

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. |

11 | |

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. |

16 | |

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/>. */ |

20 | |

21 | #ifndef TREE_SSA_SCCVN_H |

22 | #define TREE_SSA_SCCVN_H |

23 | |

24 | /* In tree-ssa-sccvn.c */ |

25 | bool expressions_equal_p (tree, tree); |

26 | |

27 | |

28 | /* TOP of the VN lattice. */ |

29 | extern tree VN_TOP; |

30 | |

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 |

34 | repeatedly. */ |

35 | |

36 | typedef struct vn_nary_op_s |

37 | { |

38 | /* Unique identify that all expressions with the same value have. */ |

39 | unsigned int value_id; |

40 | ENUM_BITFIELD(tree_code) opcode : 16; |

41 | unsigned length : 16; |

42 | hashval_t hashcode; |

43 | tree result; |

44 | tree type; |

45 | tree op[1]; |

46 | } *vn_nary_op_t; |

47 | typedef const struct vn_nary_op_s *const_vn_nary_op_t; |

48 | |

49 | /* Return the size of a vn_nary_op_t with LENGTH operands. */ |

50 | |

51 | static inline size_t |

52 | sizeof_vn_nary_op (unsigned int length) |

53 | { |

54 | return sizeof (struct vn_nary_op_s) + sizeof (tree) * length - sizeof (tree); |

55 | } |

56 | |

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. */ |

62 | |

63 | typedef struct vn_phi_s |

64 | { |

65 | /* Unique identifier that all expressions with the same value have. */ |

66 | unsigned int value_id; |

67 | hashval_t hashcode; |

68 | vec<tree> phiargs; |

69 | basic_block block; |

70 | /* Controlling condition lhs/rhs. */ |

71 | tree cclhs; |

72 | tree ccrhs; |

73 | tree type; |

74 | tree result; |

75 | } *vn_phi_t; |

76 | typedef const struct vn_phi_s *const_vn_phi_t; |

77 | |

78 | /* Reference operands only exist in reference operations structures. |

79 | They consist of an opcode, type, and some number of operands. For |

80 | a given opcode, some, all, or none of the operands may be used. |

81 | The operands are there to store the information that makes up the |

82 | portion of the addressing calculation that opcode performs. */ |

83 | |

84 | typedef struct vn_reference_op_struct |

85 | { |

86 | ENUM_BITFIELD(tree_code) opcode : 16; |

87 | /* Dependence info, used for [TARGET_]MEM_REF only. */ |

88 | unsigned short clique; |

89 | unsigned short base; |

90 | /* 1 for instrumented calls. */ |

91 | unsigned with_bounds : 1; |

92 | unsigned reverse : 1; |

93 | /* For storing TYPE_ALIGN for array ref element size computation. */ |

94 | unsigned align : 6; |

95 | /* Constant offset this op adds or -1 if it is variable. */ |

96 | HOST_WIDE_INT off; |

97 | tree type; |

98 | tree op0; |

99 | tree op1; |

100 | tree op2; |

101 | } vn_reference_op_s; |

102 | typedef vn_reference_op_s *vn_reference_op_t; |

103 | typedef const vn_reference_op_s *const_vn_reference_op_t; |

104 | |

105 | inline unsigned |

106 | vn_ref_op_align_unit (vn_reference_op_t op) |

107 | { |

108 | return op->align ? ((unsigned)1 << (op->align - 1)) / BITS_PER_UNIT : 0; |

109 | } |

110 | |

111 | /* A reference operation in the hashtable is representation as |

112 | the vuse, representing the memory state at the time of |

113 | the operation, and a collection of operands that make up the |

114 | addressing calculation. If two vn_reference_t's have the same set |

115 | of operands, they access the same memory location. We also store |

116 | the resulting value number, and the hashcode. */ |

117 | |

118 | typedef struct vn_reference_s |

119 | { |

120 | /* Unique identifier that all expressions with the same value have. */ |

121 | unsigned int value_id; |

122 | hashval_t hashcode; |

123 | tree vuse; |

124 | alias_set_type set; |

125 | tree type; |

126 | vec<vn_reference_op_s> operands; |

127 | tree result; |

128 | tree result_vdef; |

129 | } *vn_reference_t; |

130 | typedef const struct vn_reference_s *const_vn_reference_t; |

131 | |

132 | typedef struct vn_constant_s |

133 | { |

134 | unsigned int value_id; |

135 | hashval_t hashcode; |

136 | tree constant; |

137 | } *vn_constant_t; |

138 | |

139 | enum vn_kind { VN_NONE, VN_CONSTANT, VN_NARY, VN_REFERENCE, VN_PHI }; |

140 | enum vn_kind vn_get_stmt_kind (gimple *); |

141 | |

142 | /* Hash the type TYPE using bits that distinguishes it in the |

143 | types_compatible_p sense. */ |

144 | |

145 | static inline hashval_t |

146 | vn_hash_type (tree type) |

147 | { |

148 | return (INTEGRAL_TYPE_P (type) |

149 | + (INTEGRAL_TYPE_P (type) |

150 | ? TYPE_PRECISION (type) + TYPE_UNSIGNED (type) : 0)); |

151 | } |

152 | |

153 | /* Hash the constant CONSTANT with distinguishing type incompatible |

154 | constants in the types_compatible_p sense. */ |

155 | |

156 | static inline hashval_t |

157 | vn_hash_constant_with_type (tree constant) |

158 | { |

159 | inchash::hash hstate; |

160 | inchash::add_expr (constant, hstate); |

161 | hstate.merge_hash (vn_hash_type (TREE_TYPE (constant))); |

162 | return hstate.end (); |

163 | } |

164 | |

165 | /* Compare the constants C1 and C2 with distinguishing type incompatible |

166 | constants in the types_compatible_p sense. */ |

167 | |

168 | static inline bool |

169 | vn_constant_eq_with_type (tree c1, tree c2) |

170 | { |

171 | return (expressions_equal_p (c1, c2) |

172 | && types_compatible_p (TREE_TYPE (c1), TREE_TYPE (c2))); |

173 | } |

174 | |

175 | typedef struct vn_ssa_aux |

176 | { |

177 | /* Value number. This may be an SSA name or a constant. */ |

178 | tree valnum; |

179 | /* Statements to insert if needs_insertion is true. */ |

180 | gimple_seq expr; |

181 | |

182 | /* Saved SSA name info. */ |

183 | tree_ssa_name::ssa_name_info_type info; |

184 | |

185 | /* Unique identifier that all expressions with the same value have. */ |

186 | unsigned int value_id; |

187 | |

188 | /* SCC information. */ |

189 | unsigned int dfsnum; |

190 | unsigned int low; |

191 | unsigned visited : 1; |

192 | unsigned on_sccstack : 1; |

193 | |

194 | /* Whether the SSA_NAME has been value numbered already. This is |

195 | only saying whether visit_use has been called on it at least |

196 | once. It cannot be used to avoid visitation for SSA_NAME's |

197 | involved in non-singleton SCC's. */ |

198 | unsigned use_processed : 1; |

199 | |

200 | /* Whether the SSA_NAME has no defining statement and thus an |

201 | insertion of such with EXPR as definition is required before |

202 | a use can be created of it. */ |

203 | unsigned needs_insertion : 1; |

204 | |

205 | /* Whether range-info is anti-range. */ |

206 | unsigned range_info_anti_range_p : 1; |

207 | } *vn_ssa_aux_t; |

208 | |

209 | enum vn_lookup_kind { VN_NOWALK, VN_WALK, VN_WALKREWRITE }; |

210 | |

211 | /* Return the value numbering info for an SSA_NAME. */ |

212 | bool has_VN_INFO (tree); |

213 | extern vn_ssa_aux_t VN_INFO (tree); |

214 | extern vn_ssa_aux_t VN_INFO_GET (tree); |

215 | tree vn_get_expr_for (tree); |

216 | void run_scc_vn (vn_lookup_kind); |

217 | unsigned int vn_eliminate (bitmap); |

218 | void free_scc_vn (void); |

219 | void scc_vn_restore_ssa_info (void); |

220 | tree vn_nary_op_lookup (tree, vn_nary_op_t *); |

221 | tree vn_nary_op_lookup_stmt (gimple *, vn_nary_op_t *); |

222 | tree vn_nary_op_lookup_pieces (unsigned int, enum tree_code, |

223 | tree, tree *, vn_nary_op_t *); |

224 | vn_nary_op_t vn_nary_op_insert (tree, tree); |

225 | vn_nary_op_t vn_nary_op_insert_pieces (unsigned int, enum tree_code, |

226 | tree, tree *, tree, unsigned int); |

227 | bool ao_ref_init_from_vn_reference (ao_ref *, alias_set_type, tree, |

228 | vec<vn_reference_op_s> ); |

229 | vec<vn_reference_op_s> vn_reference_operands_for_lookup (tree); |

230 | tree vn_reference_lookup_pieces (tree, alias_set_type, tree, |

231 | vec<vn_reference_op_s> , |

232 | vn_reference_t *, vn_lookup_kind); |

233 | tree vn_reference_lookup (tree, tree, vn_lookup_kind, vn_reference_t *, bool); |

234 | void vn_reference_lookup_call (gcall *, vn_reference_t *, vn_reference_t); |

235 | vn_reference_t vn_reference_insert_pieces (tree, alias_set_type, tree, |

236 | vec<vn_reference_op_s> , |

237 | tree, unsigned int); |

238 | |

239 | bool vn_nary_op_eq (const_vn_nary_op_t const vno1, |

240 | const_vn_nary_op_t const vno2); |

241 | bool vn_nary_may_trap (vn_nary_op_t); |

242 | bool vn_reference_eq (const_vn_reference_t const, const_vn_reference_t const); |

243 | unsigned int get_max_value_id (void); |

244 | unsigned int get_next_value_id (void); |

245 | unsigned int get_constant_value_id (tree); |

246 | unsigned int get_or_alloc_constant_value_id (tree); |

247 | bool value_id_constant_p (unsigned int); |

248 | tree fully_constant_vn_reference_p (vn_reference_t); |

249 | tree vn_nary_simplify (vn_nary_op_t); |

250 | |

251 | /* Valueize NAME if it is an SSA name, otherwise just return it. */ |

252 | |

253 | static inline tree |

254 | vn_valueize (tree name) |

255 | { |

256 | if (TREE_CODE (name) == SSA_NAME) |

257 | { |

258 | tree tem = VN_INFO (name)->valnum; |

259 | return tem == VN_TOP ? name : tem; |

260 | } |

261 | return name; |

262 | } |

263 | |

264 | /* Get at the original range info for NAME. */ |

265 | |

266 | inline range_info_def * |

267 | VN_INFO_RANGE_INFO (tree name) |

268 | { |

269 | return (VN_INFO (name)->info.range_info |

270 | ? VN_INFO (name)->info.range_info |

271 | : SSA_NAME_RANGE_INFO (name)); |

272 | } |

273 | |

274 | /* Whether the original range info of NAME is an anti-range. */ |

275 | |

276 | inline bool |

277 | VN_INFO_ANTI_RANGE_P (tree name) |

278 | { |

279 | return (VN_INFO (name)->info.range_info |

280 | ? VN_INFO (name)->range_info_anti_range_p |

281 | : SSA_NAME_ANTI_RANGE_P (name)); |

282 | } |

283 | |

284 | /* Get at the original range info kind for NAME. */ |

285 | |

286 | inline value_range_type |

287 | VN_INFO_RANGE_TYPE (tree name) |

288 | { |

289 | return VN_INFO_ANTI_RANGE_P (name) ? VR_ANTI_RANGE : VR_RANGE; |

290 | } |

291 | |

292 | /* Get at the original pointer info for NAME. */ |

293 | |

294 | inline ptr_info_def * |

295 | VN_INFO_PTR_INFO (tree name) |

296 | { |

297 | return (VN_INFO (name)->info.ptr_info |

298 | ? VN_INFO (name)->info.ptr_info |

299 | : SSA_NAME_PTR_INFO (name)); |

300 | } |

301 | |

302 | #endif /* TREE_SSA_SCCVN_H */ |

303 |