1 | /* Data structures and function declarations for the SSA value propagation |
2 | engine. |
3 | Copyright (C) 2004-2017 Free Software Foundation, Inc. |
4 | Contributed by Diego Novillo <dnovillo@redhat.com> |
5 | |
6 | This file is part of GCC. |
7 | |
8 | GCC is free software; you can redistribute it and/or modify |
9 | it under the terms of the GNU General Public License as published by |
10 | the Free Software Foundation; either version 3, or (at your option) |
11 | any later version. |
12 | |
13 | GCC is distributed in the hope that it will be useful, |
14 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
16 | GNU General Public License 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 _TREE_SSA_PROPAGATE_H |
23 | #define _TREE_SSA_PROPAGATE_H 1 |
24 | |
25 | /* If SIM_P is true, statement S will be simulated again. */ |
26 | |
27 | static inline void |
28 | prop_set_simulate_again (gimple *s, bool visit_p) |
29 | { |
30 | gimple_set_visited (s, visit_p); |
31 | } |
32 | |
33 | /* Return true if statement T should be simulated again. */ |
34 | |
35 | static inline bool |
36 | prop_simulate_again_p (gimple *s) |
37 | { |
38 | return gimple_visited_p (s); |
39 | } |
40 | |
41 | /* Lattice values used for propagation purposes. Specific instances |
42 | of a propagation engine must return these values from the statement |
43 | and PHI visit functions to direct the engine. */ |
44 | enum ssa_prop_result { |
45 | /* The statement produces nothing of interest. No edges will be |
46 | added to the work lists. */ |
47 | SSA_PROP_NOT_INTERESTING, |
48 | |
49 | /* The statement produces an interesting value. The set SSA_NAMEs |
50 | returned by SSA_PROP_VISIT_STMT should be added to |
51 | INTERESTING_SSA_EDGES. If the statement being visited is a |
52 | conditional jump, SSA_PROP_VISIT_STMT should indicate which edge |
53 | out of the basic block should be marked executable. */ |
54 | SSA_PROP_INTERESTING, |
55 | |
56 | /* The statement produces a varying (i.e., useless) value and |
57 | should not be simulated again. If the statement being visited |
58 | is a conditional jump, all the edges coming out of the block |
59 | will be considered executable. */ |
60 | SSA_PROP_VARYING |
61 | }; |
62 | |
63 | |
64 | extern bool valid_gimple_rhs_p (tree); |
65 | extern void move_ssa_defining_stmt_for_defs (gimple *, gimple *); |
66 | extern bool update_gimple_call (gimple_stmt_iterator *, tree, int, ...); |
67 | extern bool update_call_from_tree (gimple_stmt_iterator *, tree); |
68 | extern bool stmt_makes_single_store (gimple *); |
69 | extern bool may_propagate_copy (tree, tree); |
70 | extern bool may_propagate_copy_into_stmt (gimple *, tree); |
71 | extern bool may_propagate_copy_into_asm (tree); |
72 | extern void propagate_value (use_operand_p, tree); |
73 | extern void replace_exp (use_operand_p, tree); |
74 | extern void propagate_tree_value (tree *, tree); |
75 | extern void propagate_tree_value_into_stmt (gimple_stmt_iterator *, tree); |
76 | |
77 | /* Public interface into the SSA propagation engine. Clients should inherit |
78 | from this class and provide their own visitors. */ |
79 | |
80 | class ssa_propagation_engine |
81 | { |
82 | public: |
83 | |
84 | virtual ~ssa_propagation_engine (void) { } |
85 | |
86 | /* Virtual functions the clients must provide to visit statements |
87 | and phi nodes respectively. */ |
88 | virtual enum ssa_prop_result visit_stmt (gimple *, edge *, tree *) = 0; |
89 | virtual enum ssa_prop_result visit_phi (gphi *) = 0; |
90 | |
91 | /* Main interface into the propagation engine. */ |
92 | void ssa_propagate (void); |
93 | |
94 | private: |
95 | /* Internal implementation details. */ |
96 | void simulate_stmt (gimple *stmt); |
97 | void process_ssa_edge_worklist (void); |
98 | void simulate_block (basic_block); |
99 | |
100 | }; |
101 | |
102 | class substitute_and_fold_engine |
103 | { |
104 | public: |
105 | virtual ~substitute_and_fold_engine (void) { } |
106 | virtual bool fold_stmt (gimple_stmt_iterator *) { return false; } |
107 | virtual tree get_value (tree) { return NULL_TREE; } |
108 | |
109 | bool substitute_and_fold (void); |
110 | bool replace_uses_in (gimple *); |
111 | bool replace_phi_args_in (gphi *); |
112 | }; |
113 | |
114 | #endif /* _TREE_SSA_PROPAGATE_H */ |
115 | |