blob: 78e2d1b81fa190d617323b0a8acd91d955b13675 [file] [log] [blame]
/* Support routines for value queries.
Copyright (C) 2020-2022 Free Software Foundation, Inc.
Contributed by Aldy Hernandez <aldyh@redhat.com> and
Andrew Macleod <amacleod@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 GCC_QUERY_H
#define GCC_QUERY_H
#include "value-relation.h"
// The value_query class is used by optimization passes that require
// valueizing SSA names in terms of a tree value, but have no neeed
// for ranges.
//
// value_of_expr must be provided. The default for value_on_edge and
// value_of_stmt is to call value_of_expr.
//
// This implies the valuation is global in nature. If a pass can make
// use of more specific information, it can override the other queries.
//
// Proper usage of the correct query in passes will enable other
// valuation mechanisms to produce more precise results.
class value_query
{
public:
value_query () { }
// Return the singleton expression for EXPR at a gimple statement,
// or NULL if none found.
virtual tree value_of_expr (tree expr, gimple * = NULL) = 0;
// Return the singleton expression for EXPR at an edge, or NULL if
// none found.
virtual tree value_on_edge (edge, tree expr);
// Return the singleton expression for the LHS of a gimple
// statement, assuming an (optional) initial value of NAME. Returns
// NULL if none found.
//
// Note that this method calculates the range the LHS would have
// *after* the statement has executed.
virtual tree value_of_stmt (gimple *, tree name = NULL);
private:
DISABLE_COPY_AND_ASSIGN (value_query);
};
// The range_query class is used by optimization passes which are
// range aware.
//
// range_of_expr must be provided. The default for range_on_edge and
// range_of_stmt is to call range_of_expr. If a pass can make use of
// more specific information, then it can override the other queries.
//
// The default for the value_* routines is to call the equivalent
// range_* routines, check if the range is a singleton, and return it
// if so.
//
// The get_value_range method is currently provided for compatibility
// with vr-values. It will be deprecated when possible.
class range_query : public value_query
{
public:
range_query ();
virtual ~range_query ();
virtual tree value_of_expr (tree expr, gimple * = NULL) OVERRIDE;
virtual tree value_on_edge (edge, tree expr) OVERRIDE;
virtual tree value_of_stmt (gimple *, tree name = NULL) OVERRIDE;
// These are the range equivalents of the value_* methods. Instead
// of returning a singleton, they calculate a range and return it in
// R. TRUE is returned on success or FALSE if no range was found.
//
// Note that range_of_expr must always return TRUE unless ranges are
// unsupported for EXPR's type (supports_type_p is false).
virtual bool range_of_expr (irange &r, tree expr, gimple * = NULL) = 0;
virtual bool range_on_edge (irange &r, edge, tree expr);
virtual bool range_of_stmt (irange &r, gimple *, tree name = NULL);
// Query if there is any relation between SSA1 and SSA2.
relation_kind query_relation (gimple *s, tree ssa1, tree ssa2,
bool get_range = true);
relation_kind query_relation (edge e, tree ssa1, tree ssa2,
bool get_range = true);
// If present, Access relation oracle for more advanced uses.
inline relation_oracle *oracle () const { return m_oracle; }
// DEPRECATED: This method is used from vr-values. The plan is to
// rewrite all uses of it to the above API.
virtual const class value_range_equiv *get_value_range (const_tree,
gimple * = NULL);
virtual void dump (FILE *);
protected:
class value_range_equiv *allocate_value_range_equiv ();
void free_value_range_equiv (class value_range_equiv *);
bool get_tree_range (irange &r, tree expr, gimple *stmt);
bool get_arith_expr_range (irange &r, tree expr, gimple *stmt);
relation_oracle *m_oracle;
private:
class equiv_allocator *equiv_alloc;
};
// Global ranges for SSA names using SSA_NAME_RANGE_INFO.
class global_range_query : public range_query
{
public:
bool range_of_expr (irange &r, tree expr, gimple * = NULL) OVERRIDE;
};
extern global_range_query global_ranges;
inline range_query *
get_global_range_query ()
{
return &global_ranges;
}
/* Returns the currently active range access class. When there is no active
range class, global ranges are used. Never returns null. */
ATTRIBUTE_RETURNS_NONNULL inline range_query *
get_range_query (const struct function *fun)
{
return fun->x_range_query ? fun->x_range_query : &global_ranges;
}
extern value_range gimple_range_global (tree name);
extern bool update_global_range (irange &r, tree name);
#endif // GCC_QUERY_H