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15 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
16 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * @brief peephole optimisation framework
23 * @author Matthias Braun
30 extern ir_node **register_values;
32 static inline ir_node *be_peephole_get_value(unsigned register_idx)
34 return register_values[register_idx];
37 static inline ir_node *be_peephole_get_reg_value(const arch_register_t *reg)
39 unsigned register_idx = reg->global_index;
40 return be_peephole_get_value(register_idx);
44 * Datatype of the generic op handler for optimisation.
46 typedef void (*peephole_opt_func) (ir_node *node);
49 * Notify the peephole phase about a newly added node, so it can update its
50 * internal state. This is not needed for the new node, when
51 * be_peephole_exchange() is used.
52 * Note: Contrary to normal exchange you mustn't remove the node from the
53 * schedule either before exchange. Exchange will do that for you.
55 void be_peephole_new_node(ir_node *nw);
58 * When doing peephole optimisation use this function instead of plain
59 * exchange(), so it can update its internal state. */
60 void be_peephole_exchange(ir_node *old, ir_node *nw);
63 * Tries to optimize a beIncSp node with its previous IncSP node.
64 * Must be run from a be_peephole_opt() context.
66 * @param node a be_IncSP node
68 * @return the new IncSP node or node itself
70 ir_node *be_peephole_IncSP_IncSP(ir_node *node);
72 bool be_has_only_one_user(ir_node *node);
75 * In a scheduled program with registers assigned,
76 * checks wether @p node can be moved before @p before without changing program
79 * Note: It is allowed to use this function without being in a peephole
82 bool be_can_move_down(ir_heights_t *heights, const ir_node *node,
83 const ir_node *before);
85 bool be_can_move_up(ir_heights_t *heights, const ir_node *node,
86 const ir_node *after);
89 * Do peephole optimisations. It traverses the schedule of all blocks in
90 * backward direction. The register_values variable indicates which (live)
91 * values are stored in which register.
92 * The generic op handler is called for each node if it exists. That's where
93 * backend specific optimisations should be performed based on the
94 * register-liveness information.
96 void be_peephole_opt(ir_graph *irg);