1 | /* Header file for gimple range GORI structures. |
2 | Copyright (C) 2017-2023 Free Software Foundation, Inc. |
3 | Contributed by Andrew MacLeod <amacleod@redhat.com> |
4 | and Aldy Hernandez <aldyh@redhat.com>. |
5 | |
6 | This file is part of GCC. |
7 | |
8 | GCC is free software; you can redistribute it and/or modify it under |
9 | the terms of the GNU General Public License as published by the Free |
10 | Software Foundation; either version 3, or (at your option) any later |
11 | version. |
12 | |
13 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
14 | WARRANTY; without even the implied warranty of MERCHANTABILITY or |
15 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
16 | for more details. |
17 | |
18 | You should have received a copy of the GNU General Public License |
19 | along with GCC; see the file COPYING3. If not see |
20 | <http://www.gnu.org/licenses/>. */ |
21 | |
22 | #ifndef GCC_GIMPLE_RANGE_GORI_H |
23 | #define GCC_GIMPLE_RANGE_GORI_H |
24 | |
25 | // RANGE_DEF_CHAIN is used to determine which SSA names in a block can |
26 | // have range information calculated for them, and what the |
27 | // dependencies on each other are. |
28 | |
29 | class range_def_chain |
30 | { |
31 | public: |
32 | range_def_chain (); |
33 | ~range_def_chain (); |
34 | tree depend1 (tree name) const; |
35 | tree depend2 (tree name) const; |
36 | bool in_chain_p (tree name, tree def); |
37 | bool chain_import_p (tree name, tree import); |
38 | void register_dependency (tree name, tree ssa1, basic_block bb = NULL); |
39 | void dump (FILE *f, basic_block bb, const char *prefix = NULL); |
40 | protected: |
41 | bool has_def_chain (tree name); |
42 | bool def_chain_in_bitmap_p (tree name, bitmap b); |
43 | void add_def_chain_to_bitmap (bitmap b, tree name); |
44 | bitmap get_def_chain (tree name); |
45 | bitmap get_imports (tree name); |
46 | bitmap_obstack m_bitmaps; |
47 | private: |
48 | struct rdc { |
49 | unsigned int ssa1; // First direct dependency |
50 | unsigned int ssa2; // Second direct dependency |
51 | bitmap bm; // All dependencies |
52 | bitmap m_import; |
53 | }; |
54 | vec<rdc> m_def_chain; // SSA_NAME : def chain components. |
55 | void set_import (struct rdc &data, tree imp, bitmap b); |
56 | int m_logical_depth; |
57 | }; |
58 | |
59 | // Return the first direct dependency for NAME, if there is one. |
60 | // Direct dependencies are those which occur on the definition statement. |
61 | // Only the first 2 such names are cached. |
62 | |
63 | inline tree |
64 | range_def_chain::depend1 (tree name) const |
65 | { |
66 | unsigned v = SSA_NAME_VERSION (name); |
67 | if (v >= m_def_chain.length ()) |
68 | return NULL_TREE; |
69 | unsigned v1 = m_def_chain[v].ssa1; |
70 | if (!v1) |
71 | return NULL_TREE; |
72 | return ssa_name (v1); |
73 | } |
74 | |
75 | // Return the second direct dependency for NAME, if there is one. |
76 | |
77 | inline tree |
78 | range_def_chain::depend2 (tree name) const |
79 | { |
80 | unsigned v = SSA_NAME_VERSION (name); |
81 | if (v >= m_def_chain.length ()) |
82 | return NULL_TREE; |
83 | unsigned v2 = m_def_chain[v].ssa2; |
84 | if (!v2) |
85 | return NULL_TREE; |
86 | return ssa_name (v2); |
87 | } |
88 | |
89 | // GORI_MAP is used to accumulate what SSA names in a block can |
90 | // generate range information, and provides tools for the block ranger |
91 | // to enable it to efficiently calculate these ranges. |
92 | |
93 | class gori_map : public range_def_chain |
94 | { |
95 | public: |
96 | gori_map (); |
97 | ~gori_map (); |
98 | |
99 | bool is_export_p (tree name, basic_block bb = NULL); |
100 | bool is_import_p (tree name, basic_block bb); |
101 | bitmap exports (basic_block bb); |
102 | bitmap imports (basic_block bb); |
103 | void set_range_invariant (tree name, bool invariant = true); |
104 | |
105 | void dump (FILE *f); |
106 | void dump (FILE *f, basic_block bb, bool verbose = true); |
107 | private: |
108 | vec<bitmap> m_outgoing; // BB: Outgoing ranges calculable on edges |
109 | vec<bitmap> m_incoming; // BB: Incoming ranges which can affect exports. |
110 | bitmap m_maybe_variant; // Names which might have outgoing ranges. |
111 | void maybe_add_gori (tree name, basic_block bb); |
112 | void calculate_gori (basic_block bb); |
113 | }; |
114 | |
115 | |
116 | // This class is used to determine which SSA_NAMES can have ranges |
117 | // calculated for them on outgoing edges from basic blocks. This represents |
118 | // ONLY the effect of the basic block edge->src on a range. |
119 | // |
120 | // There are 2 primary entry points: |
121 | // |
122 | // has_edge_range_p (tree name, edge e) |
123 | // returns true if the outgoing edge *may* be able to produce range |
124 | // information for ssa_name NAME on edge E. |
125 | // FALSE is returned if this edge does not affect the range of NAME. |
126 | // if no edge is specified, return TRUE if name may have a value calculated |
127 | // on *ANY* edge that has been seen. FALSE indicates that the global value |
128 | // is applicable everywhere that has been processed. |
129 | // |
130 | // outgoing_edge_range_p (vrange &range, edge e, tree name) |
131 | // Actually does the calculation of RANGE for name on E |
132 | // This represents application of whatever static range effect edge E |
133 | // may have on NAME, not any cumulative effect. |
134 | |
135 | // There are also some internal APIs |
136 | // |
137 | // ssa_range_in_bb () is an internal routine which is used to start any |
138 | // calculation chain using SSA_NAMES which come from outside the block. ie |
139 | // a_2 = b_4 - 8 |
140 | // if (a_2 < 30) |
141 | // on the true edge, a_2 is known to be [0, 29] |
142 | // b_4 can be calculated as [8, 37] |
143 | // during this calculation, b_4 is considered an "import" and ssa_range_in_bb |
144 | // is queried for a starting range which is used in the calculation. |
145 | // A default value of VARYING provides the raw static info for the edge. |
146 | // |
147 | // If there is any known range for b_4 coming into this block, it can refine |
148 | // the results. This allows for cascading results to be propagated. |
149 | // if b_4 is [100, 200] on entry to the block, feeds into the calculation |
150 | // of a_2 = [92, 192], and finally on the true edge the range would be |
151 | // an empty range [] because it is not possible for the true edge to be taken. |
152 | // |
153 | // expr_range_in_bb is simply a wrapper which calls ssa_range_in_bb for |
154 | // SSA_NAMES and otherwise simply calculates the range of the expression. |
155 | // |
156 | // The constructor takes a flag value to use on edges to check for the |
157 | // NON_EXECUTABLE_EDGE property. The zero default means no flag is checked. |
158 | // All value requests from NON_EXECUTABLE_EDGE edges are returned UNDEFINED. |
159 | // |
160 | // The remaining routines are internal use only. |
161 | |
162 | class value_relation; |
163 | |
164 | class gori_compute : public gori_map |
165 | { |
166 | public: |
167 | gori_compute (int not_executable_flag = 0); |
168 | bool outgoing_edge_range_p (vrange &r, edge e, tree name, range_query &q); |
169 | bool condexpr_adjust (vrange &r1, vrange &r2, gimple *s, tree cond, tree op1, |
170 | tree op2, fur_source &src); |
171 | bool has_edge_range_p (tree name, basic_block bb = NULL); |
172 | bool has_edge_range_p (tree name, edge e); |
173 | void dump (FILE *f); |
174 | bool compute_operand_range (vrange &r, gimple *stmt, const vrange &lhs, |
175 | tree name, class fur_source &src, |
176 | value_relation *rel = NULL); |
177 | private: |
178 | bool refine_using_relation (tree op1, vrange &op1_range, |
179 | tree op2, vrange &op2_range, |
180 | fur_source &src, relation_kind k); |
181 | bool may_recompute_p (tree name, edge e, int depth = -1); |
182 | bool may_recompute_p (tree name, basic_block bb = NULL, int depth = -1); |
183 | bool compute_operand_range_switch (vrange &r, gswitch *s, const vrange &lhs, |
184 | tree name, fur_source &src); |
185 | bool compute_operand1_range (vrange &r, gimple_range_op_handler &handler, |
186 | const vrange &lhs, fur_source &src, |
187 | value_relation *rel = NULL); |
188 | bool compute_operand2_range (vrange &r, gimple_range_op_handler &handler, |
189 | const vrange &lhs, fur_source &src, |
190 | value_relation *rel = NULL); |
191 | bool compute_operand1_and_operand2_range (vrange &r, |
192 | gimple_range_op_handler &handler, |
193 | const vrange &lhs, tree name, |
194 | fur_source &src, |
195 | value_relation *rel = NULL); |
196 | void compute_logical_operands (vrange &true_range, vrange &false_range, |
197 | gimple_range_op_handler &handler, |
198 | const irange &lhs, tree name, fur_source &src, |
199 | tree op, bool op_in_chain); |
200 | bool logical_combine (vrange &r, enum tree_code code, const irange &lhs, |
201 | const vrange &op1_true, const vrange &op1_false, |
202 | const vrange &op2_true, const vrange &op2_false); |
203 | int_range<2> m_bool_zero; // Boolean false cached. |
204 | int_range<2> m_bool_one; // Boolean true cached. |
205 | |
206 | gimple_outgoing_range outgoing; // Edge values for COND_EXPR & SWITCH_EXPR. |
207 | range_tracer tracer; |
208 | int m_not_executable_flag; |
209 | }; |
210 | |
211 | // These APIs are used to query GORI if there are ranges generated on an edge. |
212 | // GORI_ON_EDGE is used to get all the ranges at once (returned in an |
213 | // ssa_cache structure). |
214 | // GORI_NAME_ON_EDGE is used to simply ask if NAME has a range on edge E |
215 | |
216 | // Fill ssa-cache R with any outgoing ranges on edge E, using OGR and QUERY. |
217 | bool gori_on_edge (class ssa_cache &r, edge e, |
218 | range_query *query = NULL, |
219 | gimple_outgoing_range *ogr = NULL); |
220 | |
221 | // Query if NAME has an outgoing range on edge E, and return it in R if so. |
222 | // Note this doesnt use ranger, its a static GORI analysis of the range in |
223 | // block e->src and is based on any branch at the exit of that block. |
224 | bool gori_name_on_edge (vrange &r, tree name, edge e, range_query *q = NULL); |
225 | |
226 | // For each name that is an import into BB's exports.. |
227 | #define FOR_EACH_GORI_IMPORT_NAME(gori, bb, name) \ |
228 | for (gori_export_iterator iter ((gori).imports ((bb))); \ |
229 | ((name) = iter.get_name ()); \ |
230 | iter.next ()) |
231 | |
232 | // For each name possibly exported from block BB. |
233 | #define FOR_EACH_GORI_EXPORT_NAME(gori, bb, name) \ |
234 | for (gori_export_iterator iter ((gori).exports ((bb))); \ |
235 | ((name) = iter.get_name ()); \ |
236 | iter.next ()) |
237 | |
238 | // Used to assist with iterating over the GORI export list in various ways |
239 | class gori_export_iterator { |
240 | public: |
241 | gori_export_iterator (bitmap b); |
242 | void next (); |
243 | tree get_name (); |
244 | protected: |
245 | bitmap bm; |
246 | bitmap_iterator bi; |
247 | unsigned y; |
248 | }; |
249 | |
250 | #endif // GCC_GIMPLE_RANGE_GORI_H |
251 | |