rt_gccstream/gcc/tree-ssa-propagate.h

126 lines
4.1 KiB
C

/* Data structures and function declarations for the SSA value propagation
engine.
Copyright (C) 2004, 2005, 2007, 2008 Free Software Foundation, Inc.
Contributed by Diego Novillo <dnovillo@redhat.com>
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.
GCC is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING3. If not see
<http://www.gnu.org/licenses/>. */
#ifndef _TREE_SSA_PROPAGATE_H
#define _TREE_SSA_PROPAGATE_H 1
/* If SIM_P is true, statement S will be simulated again. */
static inline void
prop_set_simulate_again (gimple s, bool visit_p)
{
gimple_set_visited (s, visit_p);
}
/* Return true if statement T should be simulated again. */
static inline bool
prop_simulate_again_p (gimple s)
{
return gimple_visited_p (s);
}
/* 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. */
SSA_PROP_NOT_INTERESTING,
/* The statement produces an interesting value. The set SSA_NAMEs
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 executable. */
SSA_PROP_INTERESTING,
/* The statement produces a varying (i.e., useless) value and
should not be simulated again. If the statement being visited
is a conditional jump, all the edges coming out of the block
will be considered executable. */
SSA_PROP_VARYING
};
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;
};
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) (gimple, edge *, tree *);
typedef enum ssa_prop_result (*ssa_prop_visit_phi_fn) (gimple);
typedef bool (*ssa_prop_fold_stmt_fn) (gimple_stmt_iterator *gsi);
/* In tree-ssa-propagate.c */
void ssa_propagate (ssa_prop_visit_stmt_fn, ssa_prop_visit_phi_fn);
bool valid_gimple_rhs_p (tree);
bool valid_gimple_call_p (tree);
void move_ssa_defining_stmt_for_defs (gimple, gimple);
bool update_call_from_tree (gimple_stmt_iterator *, tree);
bool stmt_makes_single_store (gimple);
bool substitute_and_fold (prop_value_t *, ssa_prop_fold_stmt_fn);
#endif /* _TREE_SSA_PROPAGATE_H */