#ifndef SOLVE_H
#define SOLVE_H
/** Defines methods for manipulating and analyzing boolean expressions. */
#include "IR.h"
#include "Scope.h"
#include "Bounds.h"
namespace Halide {
namespace Internal {
struct SolverResult {
Expr result;
bool fully_solved;
};
/** Attempts to collect all instances of a variable in an expression
* tree and place it as far to the left as possible, and as far up the
* tree as possible (i.e. outside most parentheses). If the expression
* is an equality or comparison, this 'solves' the equation. Returns a
* pair of Expr and bool. The Expr is the mutated expression, and the
* bool indicates whether there is a single instance of the variable
* in the result. If it is false, the expression has only been partially
* solved, and there are still multiple instances of the variable. */
EXPORT SolverResult solve_expression(
Expr e, const std::string &variable,
const Scope<Expr> &scope = Scope<Expr>::empty_scope());
/** Find the smallest interval such that the condition is either true
* or false inside of it, but definitely false outside of it. Never
* returns undefined Exprs, instead it uses variables called "pos_inf"
* and "neg_inf" to represent positive and negative infinity. */
EXPORT Interval solve_for_outer_interval(Expr c, const std::string &variable);
/** Find the largest interval such that the condition is definitely
* true inside of it, and might be true or false outside of it. */
EXPORT Interval solve_for_inner_interval(Expr c, const std::string &variable);
/** Take a conditional that includes variables that vary over some
* domain, and convert it to a more conservative (less frequently
* true) condition that doesn't depend on those variables. Formally,
* the output expr implies the input expr.
*
* The condition may be a vector condition, in which case we also
* 'and' over the vector lanes, and return a scalar result. */
Expr and_condition_over_domain(Expr c, const Scope<Interval> &varying);
EXPORT void solve_test();
}
}
#endif