#ifndef HALIDE_FAST_INTEGER_DIVIDE_H
#define HALIDE_FAST_INTEGER_DIVIDE_H
#include "IR.h"
namespace Halide {
/** Built-in images used for fast_integer_divide below. Use of
* fast_integer_divide will automatically embed the appropriate tables
* in your object file. They are declared here in case you want to do
* something non-default with them. */
namespace IntegerDivideTable {
EXPORT Buffer<uint8_t> integer_divide_table_u8();
EXPORT Buffer<uint8_t> integer_divide_table_s8();
EXPORT Buffer<uint16_t> integer_divide_table_u16();
EXPORT Buffer<uint16_t> integer_divide_table_s16();
EXPORT Buffer<uint32_t> integer_divide_table_u32();
EXPORT Buffer<uint32_t> integer_divide_table_s32();
}
/** Integer division by small values can be done exactly as multiplies
* and shifts. This function does integer division for numerators of
* various integer types (8, 16, 32 bit signed and unsigned)
* numerators and uint8 denominators. The type of the result is the
* type of the numerator. The unsigned version is faster than the
* signed version, so cast the numerator to an unsigned int if you
* know it's positive.
*
* If your divisor is compile-time constant, Halide performs a
* slightly better optimization automatically, so there's no need to
* use this function (but it won't hurt).
*
* This function vectorizes well on arm, and well on x86 for 16 and 8
* bit vectors. For 32-bit vectors on x86 you're better off using
* native integer division.
*
* Also, this routine treats division by zero as division by
* 256. I.e. it interprets the uint8 divisor as a number from 1 to 256
* inclusive.
*/
EXPORT Expr fast_integer_divide(Expr numerator, Expr denominator);
/** Use the fast integer division tables to implement a modulo
* operation via the Euclidean identity: a%b = a - (a/b)*b
*/
EXPORT Expr fast_integer_modulo(Expr numerator, Expr denominator);
}
#endif