/* Data structures and function declarations for the SSA value propagation
engine.
- Copyright (C) 2001, 2003, 2004 Free Software Foundation, Inc.
+ Copyright (C) 2004, 2005 Free Software Foundation, Inc.
Contributed by Diego Novillo <dnovillo@redhat.com>
This file is part of GCC.
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING. If not, write to
-the Free Software Foundation, 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA. */
+the Free Software Foundation, 51 Franklin Street, Fifth Floor,
+Boston, MA 02110-1301, USA. */
#ifndef _TREE_SSA_PROPAGATE_H
#define _TREE_SSA_PROPAGATE_H 1
/* Lattice values used for propagation purposes. Specific instances
of a propagation engine must return these values from the statement
and PHI visit functions to direct the engine. */
-
enum ssa_prop_result {
/* The statement produces nothing of interest. No edges will be
added to the work lists. */
returned by SSA_PROP_VISIT_STMT should be added to
INTERESTING_SSA_EDGES. If the statement being visited is a
conditional jump, SSA_PROP_VISIT_STMT should indicate which edge
- out of the basic block should be marked exectuable. */
+ out of the basic block should be marked executable. */
SSA_PROP_INTERESTING,
/* The statement produces a varying (i.e., useless) value and
};
+struct prop_value_d {
+ /* Lattice value. Each propagator is free to define its own
+ lattice and this field is only meaningful while propagating.
+ It will not be used by substitute_and_fold. */
+ unsigned lattice_val;
+
+ /* Propagated value. */
+ tree value;
+
+ /* If this value is held in an SSA name for a non-register
+ variable, this field holds the actual memory reference
+ associated with this value. This field is taken from
+ the LHS of the assignment that generated the associated SSA
+ name. However, in the case of PHI nodes, this field is copied
+ from the PHI arguments (assuming that all the arguments have
+ the same memory reference). See replace_vuses_in for a more
+ detailed description. */
+ tree mem_ref;
+};
+
+typedef struct prop_value_d prop_value_t;
+
+
+/* Type of value ranges. See value_range_d for a description of these
+ types. */
+enum value_range_type { VR_UNDEFINED, VR_RANGE, VR_ANTI_RANGE, VR_VARYING };
+
+/* Range of values that can be associated with an SSA_NAME after VRP
+ has executed. */
+struct value_range_d
+{
+ /* Lattice value represented by this range. */
+ enum value_range_type type;
+
+ /* Minimum and maximum values represented by this range. These
+ values should be interpreted as follows:
+
+ - If TYPE is VR_UNDEFINED or VR_VARYING then MIN and MAX must
+ be NULL.
+
+ - If TYPE == VR_RANGE then MIN holds the minimum value and
+ MAX holds the maximum value of the range [MIN, MAX].
+
+ - If TYPE == ANTI_RANGE the variable is known to NOT
+ take any values in the range [MIN, MAX]. */
+ tree min;
+ tree max;
+
+ /* Set of SSA names whose value ranges are equivalent to this one.
+ This set is only valid when TYPE is VR_RANGE or VR_ANTI_RANGE. */
+ bitmap equiv;
+};
+
+typedef struct value_range_d value_range_t;
+
+
/* Call-back functions used by the value propagation engine. */
typedef enum ssa_prop_result (*ssa_prop_visit_stmt_fn) (tree, edge *, tree *);
typedef enum ssa_prop_result (*ssa_prop_visit_phi_fn) (tree);
+
+/* In tree-ssa-propagate.c */
void ssa_propagate (ssa_prop_visit_stmt_fn, ssa_prop_visit_phi_fn);
tree get_rhs (tree);
bool set_rhs (tree *, tree);
+tree first_vdef (tree);
+bool stmt_makes_single_load (tree);
+bool stmt_makes_single_store (tree);
+prop_value_t *get_value_loaded_by (tree, prop_value_t *);
+bool replace_uses_in (tree, bool *, prop_value_t *);
+void substitute_and_fold (prop_value_t *, bool);
#endif /* _TREE_SSA_PROPAGATE_H */
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