1/*
2 * This file is part of the MicroPython project, http://micropython.org/
3 *
4 * The MIT License (MIT)
5 *
6 * Copyright (c) 2013, 2014 Damien P. George
7 *
8 * Permission is hereby granted, free of charge, to any person obtaining a copy
9 * of this software and associated documentation files (the "Software"), to deal
10 * in the Software without restriction, including without limitation the rights
11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12 * copies of the Software, and to permit persons to whom the Software is
13 * furnished to do so, subject to the following conditions:
14 *
15 * The above copyright notice and this permission notice shall be included in
16 * all copies or substantial portions of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
21 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24 * THE SOFTWARE.
25 */
26#ifndef MICROPY_INCLUDED_PY_SMALLINT_H
27#define MICROPY_INCLUDED_PY_SMALLINT_H
28
29#include "py/mpconfig.h"
30#include "py/misc.h"
31
32// Functions for small integer arithmetic
33
34#ifndef MP_SMALL_INT_MIN
35
36// In SMALL_INT, next-to-highest bits is used as sign, so both must match for value in range
37#if MICROPY_OBJ_REPR == MICROPY_OBJ_REPR_A || MICROPY_OBJ_REPR == MICROPY_OBJ_REPR_C
38
39#define MP_SMALL_INT_MIN ((mp_int_t)(((mp_int_t)MP_OBJ_WORD_MSBIT_HIGH) >> 1))
40#define MP_SMALL_INT_FITS(n) ((((n) ^ ((n) << 1)) & MP_OBJ_WORD_MSBIT_HIGH) == 0)
41// Mask to truncate mp_int_t to positive value
42#define MP_SMALL_INT_POSITIVE_MASK ~(MP_OBJ_WORD_MSBIT_HIGH | (MP_OBJ_WORD_MSBIT_HIGH >> 1))
43
44#elif MICROPY_OBJ_REPR == MICROPY_OBJ_REPR_B
45
46#define MP_SMALL_INT_MIN ((mp_int_t)(((mp_int_t)MP_OBJ_WORD_MSBIT_HIGH) >> 2))
47#define MP_SMALL_INT_FITS(n) ((((n) & MP_SMALL_INT_MIN) == 0) || (((n) & MP_SMALL_INT_MIN) == MP_SMALL_INT_MIN))
48// Mask to truncate mp_int_t to positive value
49#define MP_SMALL_INT_POSITIVE_MASK ~(MP_OBJ_WORD_MSBIT_HIGH | (MP_OBJ_WORD_MSBIT_HIGH >> 1) | (MP_OBJ_WORD_MSBIT_HIGH >> 2))
50
51#elif MICROPY_OBJ_REPR == MICROPY_OBJ_REPR_D
52
53#define MP_SMALL_INT_MIN ((mp_int_t)(((mp_int_t)0xffff800000000000) >> 1))
54#define MP_SMALL_INT_FITS(n) ((((n) ^ ((n) << 1)) & 0xffff800000000000) == 0)
55// Mask to truncate mp_int_t to positive value
56#define MP_SMALL_INT_POSITIVE_MASK ~(0xffff800000000000 | (0xffff800000000000 >> 1))
57
58#endif
59
60#endif
61
62#define MP_SMALL_INT_MAX ((mp_int_t)(~(MP_SMALL_INT_MIN)))
63
64bool mp_small_int_mul_overflow(mp_int_t x, mp_int_t y);
65mp_int_t mp_small_int_modulo(mp_int_t dividend, mp_int_t divisor);
66mp_int_t mp_small_int_floor_divide(mp_int_t num, mp_int_t denom);
67
68#endif // MICROPY_INCLUDED_PY_SMALLINT_H
69