3 * File name: ir/ir/irflag.h
4 * Purpose: Flags to control optimizations.
5 * Author: Christian Schaefer, Goetz Lindenmaier
9 * Copyright: (c) 1999-2003 Universität Karlsruhe
10 * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
18 * @author Christian Schaefer
25 * A container type to load/restore all optimizations
27 typedef unsigned optimization_state_t;
30 * This function enables/disables optimizations globally.
32 * If optimize == 0 no optimizations are performed at all.
33 * Default: optimize == 1.
35 void set_optimize (int value);
36 int get_optimize(void);
38 /** Enables/Disables constant folding optimization.
40 * If opt_constant_folding == 1 perform
41 * - constant expression evaluation (2 + 5 ==> 7, 3 < 2 ==> false)
42 * - algebraic simplification (a * 0 ==> 0, a or a ==> a)
43 * - simplification of tests ( !(a < b) ==> (a >= b))
44 * - refining the memory representation
45 * - remove store after load
46 * Default: opt_constant_folding == 1.
48 void set_opt_constant_folding (int value);
50 /** Enables/Disables removal of redundant Loads and Stores.
52 * - Remove Store that overwrites a just stored value (WAW).
53 * - Remove Store if it stores a value just loaded (WAR with the same value).
54 * - Remove Load that loads a value just saved (RAW with the same value).
56 void set_opt_redundant_LoadStore(int value);
58 /** Enables/Disables constant subexpression elimination.
60 * If opt_cse == 1 perform constant subexpression elimination.
61 * Default: opt_cse == 1.
63 void set_opt_cse (int value);
65 /** Enables/Disables global constant subexpression elimination.
67 * If opt_global_cse == 1 and opt_cse == 1 perform intra procedure
68 * constant subexpression elimination for floating nodes. Intra
69 * procedure cse gets the graph into state "floating". It is necessary
70 * to run pre/code motion to get the graph back into state "op_pin_state_pinned".
71 * right after a call to local_optimize with global cse turned on.
72 * Default: opt_global_cse == 0.
74 void set_opt_global_cse (int value);
76 /** Enables/Disables strength reduction.
78 * If opt_strength_red == 1 perform strength reduction.
81 * Default: opt_strength_red = 1;
83 void set_opt_strength_red (int value);
85 /** Enables/Disables unreachable code elimination.
87 * If set, evaluate conditions of conditional branch and replace the
88 * branch with a Jmp/Bad Tuple.
90 * If opt_unreachable_code == 1 replace nodes (except Block,
91 * Phi and Tuple) with a Bad predecessor by the Bad node.
92 * Default: opt_unreachable_code == 1.
94 void set_opt_unreachable_code(int value);
96 /** Enables/Disables control flow optimizations.
98 * Performs Straightening, if simplifications and loop simplifications.
99 * Sets all separate control flow flags (control_flow_straightening,
100 * weak_simplification, strong_simplification and critical_edges).
102 void set_opt_control_flow(int value);
104 /** Enables/Disables Straightening. */
105 void set_opt_control_flow_straightening(int value);
107 /** Enables/Disables if simplifications in local optimizations. */
108 void set_opt_control_flow_weak_simplification(int value);
110 /** Enables/Disables strong if and loop simplification (in optimize_cf). */
111 void set_opt_control_flow_strong_simplification(int value);
113 /** Enables/Disables removal of critical control flow edges. */
114 void set_opt_critical_edges(int value);
116 /** Enables/Disables reassociation.
118 * If opt_reassociation == 1 reassociation is performed.
119 * Default: opt_reassociation == 1.
121 void set_opt_reassociation(int value);
123 /** Enables/Disables dead node elimination.
125 * If opt_dead_node_elimination == 1 deallocate all dead nodes
126 * by copying the firm graph.
127 * Default: opt_dead_node_elimination == 1. */
128 void set_opt_dead_node_elimination (int value);
130 /** Enables/Disables dead method elimination.
132 * If opt_dead_method_elimination == 1 methods never called are
134 * Default: opt_dead_method_elimination == 1. */
135 void set_opt_dead_method_elimination (int value);
136 void set_opt_dead_method_elimination_verbose (int value);
138 /** Enable/Disables inlining.
140 * If opt_inline == 1 the inlining transformation is performed.
142 void set_opt_inline (int value);
144 /** Enable/Disable optimization of dynamic method dispatch
146 * This flag enables/disables the optimization of dynamic method dispatch.
147 * If the flag is turned on Sel nodes can be replaced by Const nodes representing
148 * the address of a function.
150 void set_opt_dyn_meth_dispatch (int value);
152 /** Enable/Disable optimization of tail-recursion calls.
154 * This flag enables/disables the optimization tail-recursion call.
155 * If the flag is turned on tail-recursion calls are optimized into loops.
157 void set_opt_tail_recursion(int value);
160 /** Enable/Disable normalizations of the firm representation.
162 * This flag guards transformations that normalize the firm representation
163 * as removing Ids and Tuples, useless Phis, replacing SymConst(id) by
164 * Const(entity) and others.
165 * The transformations guarded by this flag are not guarded by flag
167 * Many algorithms operating on firm can not deal with constructs in
168 * the non-normalized representation.
170 * @@@ ATTENTION: not all such transformations are guarded by a flag.
172 void set_opt_normalize (int value);
175 /** Enable/Disable precise exception context. */
176 void set_opt_precise_exc_context(int value);
179 * Save the current optimization state.
181 void save_optimization_state(optimization_state_t *state);
184 * Restore the current optimization state.
186 void restore_optimization_state(const optimization_state_t *state);