EliminateBoolVectors.h

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#ifndef HALIDE_IR_ELIMINATE_BOOL_VECTORS_H
#define HALIDE_IR_ELIMINATE_BOOL_VECTORS_H
 
/** \file
 * Method to eliminate vectors of booleans from IR.
 */
 
#include "Expr.h"
 
namespace Halide {
namespace Internal {
 
/** Some targets treat vectors of bools as integers of the same type that the
 * boolean operation is being used to operate on. For example, instead of
 * select(i1x8, u16x8, u16x8), the target would prefer to see select(u16x8,
 * u16x8, u16x8), where the first argument is a vector of integers representing
 * a mask. This pass converts vectors of bools to vectors of integers to meet
 * this requirement. This is done by injecting intrinsics to convert bools to
 * architecture-specific masks, and using a select_mask intrinsic instead of a
 * Select node. This also converts any intrinsics that operate on vectorized
 * conditions to a *_mask equivalent (if_then_else, require). Because the masks
 * are architecture specific, they may not be stored or loaded. On Stores, the
 * masks are converted to UInt(8) with a value of 0 or 1, which is our canonical
 * in-memory representation of a bool. */
///@{
Stmt eliminate_bool_vectors(const Stmt &s);
Expr eliminate_bool_vectors(const Expr &s);
///@}
 
/** If a type is a boolean vector, find the type that it has been
 * changed to by eliminate_bool_vectors. */
inline Type eliminated_bool_type(Type bool_type, Type other_type) {
    if (bool_type.is_vector() && bool_type.bits() == 1) {
        bool_type = bool_type.with_code(Type::Int).with_bits(other_type.bits());
    }
    return bool_type;
}
 
}  // namespace Internal
}  // namespace Halide
 
#endif