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/* Support routines for Value Range Propagation (VRP).
Copyright (C) 2016-2017 Free Software Foundation, Inc.
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 GCC_VR_VALUES_H
#define GCC_VR_VALUES_H
/* The VR_VALUES class holds the current view of range information
for all the SSA_NAMEs in the IL.
It can be used to hold context sensitive range information during
a dominator walk or it may be used to hold range information in the
standard VRP pass as ranges are propagated through the lattice to a
steady state.
This information is independent of the range information that gets
attached to SSA_NAMEs. A pass such as VRP may choose to transfer
the global information it produces into global range information that
gets attached to an SSA_NAME. It's unclear how useful that global
information will be in a world where we can compute context sensitive
range information fast or perform on-demand queries. */
class vr_values
{
public:
vr_values (void);
~vr_values (void);
value_range *get_value_range (const_tree);
void set_vr_value (tree, value_range *);
void set_defs_to_varying (gimple *);
bool update_value_range (const_tree, value_range *);
tree op_with_constant_singleton_value_range (tree);
void adjust_range_with_scev (value_range *, struct loop *, gimple *, tree);
tree vrp_evaluate_conditional (tree_code, tree, tree, gimple *);
void dump_all_value_ranges (FILE *);
void extract_range_for_var_from_comparison_expr (tree, enum tree_code,
tree, tree, value_range *);
void extract_range_from_phi_node (gphi *, value_range *);
void extract_range_basic (value_range *, gimple *);
void extract_range_from_stmt (gimple *, edge *, tree *, value_range *);
void vrp_visit_cond_stmt (gcond *, edge *);
void simplify_cond_using_ranges_2 (gcond *);
bool simplify_stmt_using_ranges (gimple_stmt_iterator *);
/* Indicate that propagation through the lattice is complete. */
void set_lattice_propagation_complete (void) { values_propagated = true; }
/* Allocate a new value_range object. */
value_range *allocate_value_range (void)
{ return vrp_value_range_pool.allocate (); }
private:
void add_equivalence (bitmap *, const_tree);
bool vrp_stmt_computes_nonzero (gimple *);
bool op_with_boolean_value_range_p (tree);
bool check_for_binary_op_overflow (enum tree_code, tree, tree, tree, bool *);
value_range get_vr_for_comparison (int);
tree compare_name_with_value (enum tree_code, tree, tree, bool *, bool);
tree compare_names (enum tree_code, tree, tree, bool *);
bool two_valued_val_range_p (tree, tree *, tree *);
tree vrp_evaluate_conditional_warnv_with_ops_using_ranges (enum tree_code,
tree, tree,
bool *);
tree vrp_evaluate_conditional_warnv_with_ops (enum tree_code,
tree, tree, bool,
bool *, bool *);
void extract_range_from_assignment (value_range *, gassign *);
void extract_range_from_assert (value_range *, tree);
void extract_range_from_ssa_name (value_range *, tree);
void extract_range_from_binary_expr (value_range *, enum tree_code,
tree, tree, tree);
void extract_range_from_unary_expr (value_range *, enum tree_code,
tree, tree);
void extract_range_from_cond_expr (value_range *, gassign *);
void extract_range_from_comparison (value_range *, enum tree_code,
tree, tree, tree);
void vrp_visit_assignment_or_call (gimple*, tree *, value_range *);
void vrp_visit_switch_stmt (gswitch *, edge *);
bool simplify_truth_ops_using_ranges (gimple_stmt_iterator *, gimple *);
bool simplify_div_or_mod_using_ranges (gimple_stmt_iterator *, gimple *);
bool simplify_abs_using_ranges (gimple_stmt_iterator *, gimple *);
bool simplify_bit_ops_using_ranges (gimple_stmt_iterator *, gimple *);
bool simplify_min_or_max_using_ranges (gimple_stmt_iterator *, gimple *);
bool simplify_cond_using_ranges_1 (gcond *);
bool simplify_switch_using_ranges (gswitch *);
bool simplify_float_conversion_using_ranges (gimple_stmt_iterator *,
gimple *);
bool simplify_internal_call_using_ranges (gimple_stmt_iterator *, gimple *);
/* Allocation pools for value_range objects. */
object_allocator<value_range> vrp_value_range_pool;
/* This probably belongs in the lattice rather than in here. */
bool values_propagated;
/* Allocations for equivalences all come from this obstack. */
bitmap_obstack vrp_equiv_obstack;
/* Value range array. After propagation, VR_VALUE[I] holds the range
of values that SSA name N_I may take. */
unsigned int num_vr_values;
value_range **vr_value;
/* For a PHI node which sets SSA name N_I, VR_COUNTS[I] holds the
number of executable edges we saw the last time we visited the
node. */
int *vr_phi_edge_counts;
};
#define VR_INITIALIZER { VR_UNDEFINED, NULL_TREE, NULL_TREE, NULL }
extern tree get_output_for_vrp (gimple *);
#endif /* GCC_VR_VALUES_H */