py/objint.c - lite/micropython - Linaro Git Browser

 /*
  * This file is part of the MicroPython project, http://micropython.org/
  *
  * The MIT License (MIT)
  *
  * Copyright (c) 2013, 2014 Damien P. George
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */

 #include <stdlib.h>
 #include <assert.h>
 #include <string.h>

 #include "py/parsenum.h"
 #include "py/smallint.h"
 #include "py/objint.h"
 #include "py/objstr.h"
 #include "py/runtime.h"
 #include "py/binary.h"

 #if MICROPY_PY_BUILTINS_FLOAT
 #include <math.h>
 #endif

 // This dispatcher function is expected to be independent of the implementation of long int
 STATIC mp_obj_t mp_obj_int_make_new(const mp_obj_type_t *type_in, size_t n_args, size_t n_kw, const mp_obj_t *args) {
     (void)type_in;
     mp_arg_check_num(n_args, n_kw, 0, 2, false);

     switch (n_args) {
         case 0:
             return MP_OBJ_NEW_SMALL_INT(0);

         case 1:
             if (MP_OBJ_IS_INT(args[0])) {
                 // already an int (small or long), just return it
                 return args[0];
             } else if (MP_OBJ_IS_STR_OR_BYTES(args[0])) {
                 // a string, parse it
                 size_t l;
                 const char *s = mp_obj_str_get_data(args[0], &l);
                 return mp_parse_num_integer(s, l, 0, NULL);
 #if MICROPY_PY_BUILTINS_FLOAT
             } else if (mp_obj_is_float(args[0])) {
                 return mp_obj_new_int_from_float(mp_obj_float_get(args[0]));
 #endif
             } else {
                 // try to convert to small int (eg from bool)
                 return MP_OBJ_NEW_SMALL_INT(mp_obj_get_int(args[0]));
             }

         case 2:
         default: {
             // should be a string, parse it
             // TODO proper error checking of argument types
             size_t l;
             const char *s = mp_obj_str_get_data(args[0], &l);
             return mp_parse_num_integer(s, l, mp_obj_get_int(args[1]), NULL);
         }
     }
 }

 #if MICROPY_PY_BUILTINS_FLOAT

 typedef enum {
     MP_FP_CLASS_FIT_SMALLINT,
     MP_FP_CLASS_FIT_LONGINT,
     MP_FP_CLASS_OVERFLOW
 } mp_fp_as_int_class_t;

 STATIC mp_fp_as_int_class_t mp_classify_fp_as_int(mp_float_t val) {
     union {
         mp_float_t f;
 #if MICROPY_FLOAT_IMPL == MICROPY_FLOAT_IMPL_FLOAT
         uint32_t i;
 #elif MICROPY_FLOAT_IMPL == MICROPY_FLOAT_IMPL_DOUBLE
         uint32_t i[2];
 #endif
     } u = {val};

     uint32_t e;
 #if MICROPY_FLOAT_IMPL == MICROPY_FLOAT_IMPL_FLOAT
     e = u.i;
 #elif MICROPY_FLOAT_IMPL == MICROPY_FLOAT_IMPL_DOUBLE
     e = u.i[MP_ENDIANNESS_LITTLE];
 #endif
 #define MP_FLOAT_SIGN_SHIFT_I32 ((MP_FLOAT_FRAC_BITS + MP_FLOAT_EXP_BITS) % 32)
 #define MP_FLOAT_EXP_SHIFT_I32 (MP_FLOAT_FRAC_BITS % 32)

     if (e & (1U << MP_FLOAT_SIGN_SHIFT_I32)) {
 #if MICROPY_FLOAT_IMPL == MICROPY_FLOAT_IMPL_DOUBLE
         e |= u.i[MP_ENDIANNESS_BIG] != 0;
 #endif
         if ((e & ~(1 << MP_FLOAT_SIGN_SHIFT_I32)) == 0) {
             // handle case of -0 (when sign is set but rest of bits are zero)
             e = 0;
         } else {
             e += ((1 << MP_FLOAT_EXP_BITS) - 1) << MP_FLOAT_EXP_SHIFT_I32;
         }
     } else {
         e &= ~((1 << MP_FLOAT_EXP_SHIFT_I32) - 1);
     }
     // 8 * sizeof(uintptr_t) counts the number of bits for a small int
     // TODO provide a way to configure this properly
     if (e <= ((8 * sizeof(uintptr_t) + MP_FLOAT_EXP_BIAS - 3) << MP_FLOAT_EXP_SHIFT_I32)) {
         return MP_FP_CLASS_FIT_SMALLINT;
     }
 #if MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_LONGLONG
     if (e <= (((sizeof(long long) * BITS_PER_BYTE) + MP_FLOAT_EXP_BIAS - 2) << MP_FLOAT_EXP_SHIFT_I32)) {
         return MP_FP_CLASS_FIT_LONGINT;
     }
 #endif
 #if MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_MPZ
     return MP_FP_CLASS_FIT_LONGINT;
 #else
     return MP_FP_CLASS_OVERFLOW;
 #endif
 }
 #undef MP_FLOAT_SIGN_SHIFT_I32
 #undef MP_FLOAT_EXP_SHIFT_I32

 mp_obj_t mp_obj_new_int_from_float(mp_float_t val) {
     int cl = fpclassify(val);
     if (cl == FP_INFINITE) {
         nlr_raise(mp_obj_new_exception_msg(&mp_type_OverflowError, "can't convert inf to int"));
     } else if (cl == FP_NAN) {
         mp_raise_ValueError("can't convert NaN to int");
     } else {
         mp_fp_as_int_class_t icl = mp_classify_fp_as_int(val);
         if (icl == MP_FP_CLASS_FIT_SMALLINT) {
             return MP_OBJ_NEW_SMALL_INT((mp_int_t)val);
         #if MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_MPZ
         } else {
             mp_obj_int_t *o = mp_obj_int_new_mpz();
             mpz_set_from_float(&o->mpz, val);
             return MP_OBJ_FROM_PTR(o);
         }
         #else
         #if MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_LONGLONG
         } else if (icl == MP_FP_CLASS_FIT_LONGINT) {
             return mp_obj_new_int_from_ll((long long)val);
         #endif
         } else {
             mp_raise_ValueError("float too big");
         }
         #endif
     }
 }

 #endif

 #if MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_LONGLONG
 typedef mp_longint_impl_t fmt_int_t;
 typedef unsigned long long fmt_uint_t;
 #else
 typedef mp_int_t fmt_int_t;
 typedef mp_uint_t fmt_uint_t;
 #endif

 void mp_obj_int_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
     (void)kind;
     // The size of this buffer is rather arbitrary. If it's not large
     // enough, a dynamic one will be allocated.
     char stack_buf[sizeof(fmt_int_t) * 4];
     char *buf = stack_buf;
     size_t buf_size = sizeof(stack_buf);
     size_t fmt_size;

     char *str = mp_obj_int_formatted(&buf, &buf_size, &fmt_size, self_in, 10, NULL, '\0', '\0');
     mp_print_str(print, str);

     if (buf != stack_buf) {
         m_del(char, buf, buf_size);
     }
 }

 STATIC const uint8_t log_base2_floor[] = {
     0, 1, 1, 2,
     2, 2, 2, 3,
     3, 3, 3, 3,
     3, 3, 3, 4,
     /* if needed, these are the values for higher bases
     4, 4, 4, 4,
     4, 4, 4, 4,
     4, 4, 4, 4,
     4, 4, 4, 5
     */
 };

 size_t mp_int_format_size(size_t num_bits, int base, const char *prefix, char comma) {
     assert(2 <= base && base <= 16);
     size_t num_digits = num_bits / log_base2_floor[base - 1] + 1;
     size_t num_commas = comma ? num_digits / 3 : 0;
     size_t prefix_len = prefix ? strlen(prefix) : 0;
     return num_digits + num_commas + prefix_len + 2; // +1 for sign, +1 for null byte
 }

 // This routine expects you to pass in a buffer and size (in *buf and *buf_size).
 // If, for some reason, this buffer is too small, then it will allocate a
 // buffer and return the allocated buffer and size in *buf and *buf_size. It
 // is the callers responsibility to free this allocated buffer.
 //
 // The resulting formatted string will be returned from this function and the
 // formatted size will be in *fmt_size.
 char *mp_obj_int_formatted(char **buf, size_t *buf_size, size_t *fmt_size, mp_const_obj_t self_in,
                            int base, const char *prefix, char base_char, char comma) {
     fmt_int_t num;
     if (MP_OBJ_IS_SMALL_INT(self_in)) {
         // A small int; get the integer value to format.
         num = MP_OBJ_SMALL_INT_VALUE(self_in);
 #if MICROPY_LONGINT_IMPL != MICROPY_LONGINT_IMPL_NONE
     } else if (MP_OBJ_IS_TYPE(self_in, &mp_type_int)) {
         // Not a small int.
 #if MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_LONGLONG
         const mp_obj_int_t *self = self_in;
         // Get the value to format; mp_obj_get_int truncates to mp_int_t.
         num = self->val;
 #else
         // Delegate to the implementation for the long int.
         return mp_obj_int_formatted_impl(buf, buf_size, fmt_size, self_in, base, prefix, base_char, comma);
 #endif
 #endif
     } else {
         // Not an int.
         **buf = '\0';
         *fmt_size = 0;
         return *buf;
     }

     char sign = '\0';
     if (num < 0) {
         num = -num;
         sign = '-';
     }

     size_t needed_size = mp_int_format_size(sizeof(fmt_int_t) * 8, base, prefix, comma);
     if (needed_size > *buf_size) {
         *buf = m_new(char, needed_size);
         *buf_size = needed_size;
     }
     char *str = *buf;

     char *b = str + needed_size;
     *(--b) = '\0';
     char *last_comma = b;

     if (num == 0) {
         *(--b) = '0';
     } else {
         do {
             // The cast to fmt_uint_t is because num is positive and we want unsigned arithmetic
             int c = (fmt_uint_t)num % base;
             num = (fmt_uint_t)num / base;
             if (c >= 10) {
                 c += base_char - 10;
             } else {
                 c += '0';
             }
             *(--b) = c;
             if (comma && num != 0 && b > str && (last_comma - b) == 3) {
                 *(--b) = comma;
                 last_comma = b;
             }
         }
         while (b > str && num != 0);
     }
     if (prefix) {
         size_t prefix_len = strlen(prefix);
         char *p = b - prefix_len;
         if (p > str) {
             b = p;
             while (*prefix) {
                 *p++ = *prefix++;
             }
         }
     }
     if (sign && b > str) {
         *(--b) = sign;
     }
     *fmt_size = *buf + needed_size - b - 1;

     return b;
 }

 #if MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_NONE

 int mp_obj_int_sign(mp_obj_t self_in) {
     mp_int_t val = mp_obj_get_int(self_in);
     if (val < 0) {
         return -1;
     } else if (val > 0) {
         return 1;
     } else {
         return 0;
     }
 }

 // This is called for operations on SMALL_INT that are not handled by mp_unary_op
 mp_obj_t mp_obj_int_unary_op(mp_unary_op_t op, mp_obj_t o_in) {
     return MP_OBJ_NULL; // op not supported
 }

 // This is called for operations on SMALL_INT that are not handled by mp_binary_op
 mp_obj_t mp_obj_int_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     return mp_obj_int_binary_op_extra_cases(op, lhs_in, rhs_in);
 }

 // This is called only with strings whose value doesn't fit in SMALL_INT
 mp_obj_t mp_obj_new_int_from_str_len(const char **str, size_t len, bool neg, unsigned int base) {
     mp_raise_msg(&mp_type_OverflowError, "long int not supported in this build");
     return mp_const_none;
 }

 // This is called when an integer larger than a SMALL_INT is needed (although val might still fit in a SMALL_INT)
 mp_obj_t mp_obj_new_int_from_ll(long long val) {
     mp_raise_msg(&mp_type_OverflowError, "small int overflow");
     return mp_const_none;
 }

 // This is called when an integer larger than a SMALL_INT is needed (although val might still fit in a SMALL_INT)
 mp_obj_t mp_obj_new_int_from_ull(unsigned long long val) {
     mp_raise_msg(&mp_type_OverflowError, "small int overflow");
     return mp_const_none;
 }

 mp_obj_t mp_obj_new_int_from_uint(mp_uint_t value) {
     // SMALL_INT accepts only signed numbers, so make sure the input
     // value fits completely in the small-int positive range.
     if ((value & ~MP_SMALL_INT_POSITIVE_MASK) == 0) {
         return MP_OBJ_NEW_SMALL_INT(value);
     }
     mp_raise_msg(&mp_type_OverflowError, "small int overflow");
     return mp_const_none;
 }

 mp_obj_t mp_obj_new_int(mp_int_t value) {
     if (MP_SMALL_INT_FITS(value)) {
         return MP_OBJ_NEW_SMALL_INT(value);
     }
     mp_raise_msg(&mp_type_OverflowError, "small int overflow");
     return mp_const_none;
 }

 mp_int_t mp_obj_int_get_truncated(mp_const_obj_t self_in) {
     return MP_OBJ_SMALL_INT_VALUE(self_in);
 }

 mp_int_t mp_obj_int_get_checked(mp_const_obj_t self_in) {
     return MP_OBJ_SMALL_INT_VALUE(self_in);
 }

 #endif // MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_NONE

 // This dispatcher function is expected to be independent of the implementation of long int
 // It handles the extra cases for integer-like arithmetic
 mp_obj_t mp_obj_int_binary_op_extra_cases(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     if (rhs_in == mp_const_false) {
         // false acts as 0
         return mp_binary_op(op, lhs_in, MP_OBJ_NEW_SMALL_INT(0));
     } else if (rhs_in == mp_const_true) {
         // true acts as 0
         return mp_binary_op(op, lhs_in, MP_OBJ_NEW_SMALL_INT(1));
     } else if (op == MP_BINARY_OP_MULTIPLY) {
         if (MP_OBJ_IS_STR(rhs_in) || MP_OBJ_IS_TYPE(rhs_in, &mp_type_bytes) || MP_OBJ_IS_TYPE(rhs_in, &mp_type_tuple) || MP_OBJ_IS_TYPE(rhs_in, &mp_type_list)) {
             // multiply is commutative for these types, so delegate to them
             return mp_binary_op(op, rhs_in, lhs_in);
         }
     }
     return MP_OBJ_NULL; // op not supported
 }

 // this is a classmethod
 STATIC mp_obj_t int_from_bytes(size_t n_args, const mp_obj_t *args) {
     // TODO: Support signed param (assumes signed=False at the moment)
     (void)n_args;

     // get the buffer info
     mp_buffer_info_t bufinfo;
     mp_get_buffer_raise(args[1], &bufinfo, MP_BUFFER_READ);

     const byte* buf = (const byte*)bufinfo.buf;
     int delta = 1;
     if (args[2] == MP_OBJ_NEW_QSTR(MP_QSTR_little)) {
         buf += bufinfo.len - 1;
         delta = -1;
     }

     mp_uint_t value = 0;
     size_t len = bufinfo.len;
     for (; len--; buf += delta) {
         #if MICROPY_LONGINT_IMPL != MICROPY_LONGINT_IMPL_NONE
         if (value > (MP_SMALL_INT_MAX >> 8)) {
             // Result will overflow a small-int so construct a big-int
             return mp_obj_int_from_bytes_impl(args[2] != MP_OBJ_NEW_QSTR(MP_QSTR_little), bufinfo.len, bufinfo.buf);
         }
         #endif
         value = (value << 8) | *buf;
     }
     return mp_obj_new_int_from_uint(value);
 }

 STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(int_from_bytes_fun_obj, 3, 4, int_from_bytes);
 STATIC MP_DEFINE_CONST_CLASSMETHOD_OBJ(int_from_bytes_obj, MP_ROM_PTR(&int_from_bytes_fun_obj));

 STATIC mp_obj_t int_to_bytes(size_t n_args, const mp_obj_t *args) {
     // TODO: Support signed param (assumes signed=False)
     (void)n_args;

     mp_int_t len = mp_obj_get_int(args[1]);
     if (len < 0) {
         mp_raise_ValueError(NULL);
     }
     bool big_endian = args[2] != MP_OBJ_NEW_QSTR(MP_QSTR_little);

     vstr_t vstr;
     vstr_init_len(&vstr, len);
     byte *data = (byte*)vstr.buf;
     memset(data, 0, len);

     #if MICROPY_LONGINT_IMPL != MICROPY_LONGINT_IMPL_NONE
     if (!MP_OBJ_IS_SMALL_INT(args[0])) {
         mp_obj_int_to_bytes_impl(args[0], big_endian, len, data);
     } else
     #endif
     {
         mp_int_t val = MP_OBJ_SMALL_INT_VALUE(args[0]);
         size_t l = MIN((size_t)len, sizeof(val));
         mp_binary_set_int(l, big_endian, data + (big_endian ? (len - l) : 0), val);
     }

     return mp_obj_new_str_from_vstr(&mp_type_bytes, &vstr);
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(int_to_bytes_obj, 3, 4, int_to_bytes);

 STATIC const mp_rom_map_elem_t int_locals_dict_table[] = {
     { MP_ROM_QSTR(MP_QSTR_from_bytes), MP_ROM_PTR(&int_from_bytes_obj) },
     { MP_ROM_QSTR(MP_QSTR_to_bytes), MP_ROM_PTR(&int_to_bytes_obj) },
 };

 STATIC MP_DEFINE_CONST_DICT(int_locals_dict, int_locals_dict_table);

 const mp_obj_type_t mp_type_int = {
     { &mp_type_type },
     .name = MP_QSTR_int,
     .print = mp_obj_int_print,
     .make_new = mp_obj_int_make_new,
     .unary_op = mp_obj_int_unary_op,
     .binary_op = mp_obj_int_binary_op,
     .locals_dict = (mp_obj_dict_t*)&int_locals_dict,
 };
	/*
	* This file is part of the MicroPython project, http://micropython.org/
	*
	* The MIT License (MIT)
	*
	* Copyright (c) 2013, 2014 Damien P. George
	*
	* Permission is hereby granted, free of charge, to any person obtaining a copy
	* of this software and associated documentation files (the "Software"), to deal
	* in the Software without restriction, including without limitation the rights
	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	* copies of the Software, and to permit persons to whom the Software is
	* furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included in
	* all copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	* THE SOFTWARE.
	*/

	#include <stdlib.h>
	#include <assert.h>
	#include <string.h>

	#include "py/parsenum.h"
	#include "py/smallint.h"
	#include "py/objint.h"
	#include "py/objstr.h"
	#include "py/runtime.h"
	#include "py/binary.h"

	#if MICROPY_PY_BUILTINS_FLOAT
	#include <math.h>
	#endif

	// This dispatcher function is expected to be independent of the implementation of long int
	STATIC mp_obj_t mp_obj_int_make_new(const mp_obj_type_t type_in, size_t n_args, size_t n_kw, const mp_obj_t args) {
	(void)type_in;
	mp_arg_check_num(n_args, n_kw, 0, 2, false);

	switch (n_args) {
	case 0:
	return MP_OBJ_NEW_SMALL_INT(0);

	case 1:
	if (MP_OBJ_IS_INT(args[0])) {
	// already an int (small or long), just return it
	return args[0];
	} else if (MP_OBJ_IS_STR_OR_BYTES(args[0])) {
	// a string, parse it
	size_t l;
	const char *s = mp_obj_str_get_data(args[0], &l);
	return mp_parse_num_integer(s, l, 0, NULL);
	#if MICROPY_PY_BUILTINS_FLOAT
	} else if (mp_obj_is_float(args[0])) {
	return mp_obj_new_int_from_float(mp_obj_float_get(args[0]));
	#endif
	} else {
	// try to convert to small int (eg from bool)
	return MP_OBJ_NEW_SMALL_INT(mp_obj_get_int(args[0]));
	}

	case 2:
	default: {
	// should be a string, parse it
	// TODO proper error checking of argument types
	size_t l;
	const char *s = mp_obj_str_get_data(args[0], &l);
	return mp_parse_num_integer(s, l, mp_obj_get_int(args[1]), NULL);
	}
	}
	}

	#if MICROPY_PY_BUILTINS_FLOAT

	typedef enum {
	MP_FP_CLASS_FIT_SMALLINT,
	MP_FP_CLASS_FIT_LONGINT,
	MP_FP_CLASS_OVERFLOW
	} mp_fp_as_int_class_t;

	STATIC mp_fp_as_int_class_t mp_classify_fp_as_int(mp_float_t val) {
	union {
	mp_float_t f;
	#if MICROPY_FLOAT_IMPL == MICROPY_FLOAT_IMPL_FLOAT
	uint32_t i;
	#elif MICROPY_FLOAT_IMPL == MICROPY_FLOAT_IMPL_DOUBLE
	uint32_t i[2];
	#endif
	} u = {val};

	uint32_t e;
	#if MICROPY_FLOAT_IMPL == MICROPY_FLOAT_IMPL_FLOAT
	e = u.i;
	#elif MICROPY_FLOAT_IMPL == MICROPY_FLOAT_IMPL_DOUBLE
	e = u.i[MP_ENDIANNESS_LITTLE];
	#endif
	#define MP_FLOAT_SIGN_SHIFT_I32 ((MP_FLOAT_FRAC_BITS + MP_FLOAT_EXP_BITS) % 32)
	#define MP_FLOAT_EXP_SHIFT_I32 (MP_FLOAT_FRAC_BITS % 32)

	if (e & (1U << MP_FLOAT_SIGN_SHIFT_I32)) {
	#if MICROPY_FLOAT_IMPL == MICROPY_FLOAT_IMPL_DOUBLE
	e \|= u.i[MP_ENDIANNESS_BIG] != 0;
	#endif
	if ((e & ~(1 << MP_FLOAT_SIGN_SHIFT_I32)) == 0) {
	// handle case of -0 (when sign is set but rest of bits are zero)
	e = 0;
	} else {
	e += ((1 << MP_FLOAT_EXP_BITS) - 1) << MP_FLOAT_EXP_SHIFT_I32;
	}
	} else {
	e &= ~((1 << MP_FLOAT_EXP_SHIFT_I32) - 1);
	}
	// 8 * sizeof(uintptr_t) counts the number of bits for a small int
	// TODO provide a way to configure this properly
	if (e <= ((8 * sizeof(uintptr_t) + MP_FLOAT_EXP_BIAS - 3) << MP_FLOAT_EXP_SHIFT_I32)) {
	return MP_FP_CLASS_FIT_SMALLINT;
	}
	#if MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_LONGLONG
	if (e <= (((sizeof(long long) * BITS_PER_BYTE) + MP_FLOAT_EXP_BIAS - 2) << MP_FLOAT_EXP_SHIFT_I32)) {
	return MP_FP_CLASS_FIT_LONGINT;
	}
	#endif
	#if MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_MPZ
	return MP_FP_CLASS_FIT_LONGINT;
	#else
	return MP_FP_CLASS_OVERFLOW;
	#endif
	}
	#undef MP_FLOAT_SIGN_SHIFT_I32
	#undef MP_FLOAT_EXP_SHIFT_I32

	mp_obj_t mp_obj_new_int_from_float(mp_float_t val) {
	int cl = fpclassify(val);
	if (cl == FP_INFINITE) {
	nlr_raise(mp_obj_new_exception_msg(&mp_type_OverflowError, "can't convert inf to int"));
	} else if (cl == FP_NAN) {
	mp_raise_ValueError("can't convert NaN to int");
	} else {
	mp_fp_as_int_class_t icl = mp_classify_fp_as_int(val);
	if (icl == MP_FP_CLASS_FIT_SMALLINT) {
	return MP_OBJ_NEW_SMALL_INT((mp_int_t)val);
	#if MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_MPZ
	} else {
	mp_obj_int_t *o = mp_obj_int_new_mpz();
	mpz_set_from_float(&o->mpz, val);
	return MP_OBJ_FROM_PTR(o);
	}
	#else
	#if MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_LONGLONG
	} else if (icl == MP_FP_CLASS_FIT_LONGINT) {
	return mp_obj_new_int_from_ll((long long)val);
	#endif
	} else {
	mp_raise_ValueError("float too big");
	}
	#endif
	}
	}

	#endif

	#if MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_LONGLONG
	typedef mp_longint_impl_t fmt_int_t;
	typedef unsigned long long fmt_uint_t;
	#else
	typedef mp_int_t fmt_int_t;
	typedef mp_uint_t fmt_uint_t;
	#endif

	void mp_obj_int_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
	(void)kind;
	// The size of this buffer is rather arbitrary. If it's not large
	// enough, a dynamic one will be allocated.
	char stack_buf[sizeof(fmt_int_t) * 4];
	char *buf = stack_buf;
	size_t buf_size = sizeof(stack_buf);
	size_t fmt_size;

	char *str = mp_obj_int_formatted(&buf, &buf_size, &fmt_size, self_in, 10, NULL, '\0', '\0');
	mp_print_str(print, str);

	if (buf != stack_buf) {
	m_del(char, buf, buf_size);
	}
	}

	STATIC const uint8_t log_base2_floor[] = {
	0, 1, 1, 2,
	2, 2, 2, 3,
	3, 3, 3, 3,
	3, 3, 3, 4,
	/* if needed, these are the values for higher bases
	4, 4, 4, 4,
	4, 4, 4, 4,
	4, 4, 4, 4,
	4, 4, 4, 5
	*/
	};

	size_t mp_int_format_size(size_t num_bits, int base, const char *prefix, char comma) {
	assert(2 <= base && base <= 16);
	size_t num_digits = num_bits / log_base2_floor[base - 1] + 1;
	size_t num_commas = comma ? num_digits / 3 : 0;
	size_t prefix_len = prefix ? strlen(prefix) : 0;
	return num_digits + num_commas + prefix_len + 2; // +1 for sign, +1 for null byte
	}

	// This routine expects you to pass in a buffer and size (in buf and buf_size).
	// If, for some reason, this buffer is too small, then it will allocate a
	// buffer and return the allocated buffer and size in buf and buf_size. It
	// is the callers responsibility to free this allocated buffer.
	//
	// The resulting formatted string will be returned from this function and the
	// formatted size will be in *fmt_size.
	char mp_obj_int_formatted(char buf, size_t buf_size, size_t *fmt_size, mp_const_obj_t self_in,
	int base, const char *prefix, char base_char, char comma) {
	fmt_int_t num;
	if (MP_OBJ_IS_SMALL_INT(self_in)) {
	// A small int; get the integer value to format.
	num = MP_OBJ_SMALL_INT_VALUE(self_in);
	#if MICROPY_LONGINT_IMPL != MICROPY_LONGINT_IMPL_NONE
	} else if (MP_OBJ_IS_TYPE(self_in, &mp_type_int)) {
	// Not a small int.
	#if MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_LONGLONG
	const mp_obj_int_t *self = self_in;
	// Get the value to format; mp_obj_get_int truncates to mp_int_t.
	num = self->val;
	#else
	// Delegate to the implementation for the long int.
	return mp_obj_int_formatted_impl(buf, buf_size, fmt_size, self_in, base, prefix, base_char, comma);
	#endif
	#endif
	} else {
	// Not an int.
	**buf = '\0';
	*fmt_size = 0;
	return *buf;
	}

	char sign = '\0';
	if (num < 0) {
	num = -num;
	sign = '-';
	}

	size_t needed_size = mp_int_format_size(sizeof(fmt_int_t) * 8, base, prefix, comma);
	if (needed_size > *buf_size) {
	*buf = m_new(char, needed_size);
	*buf_size = needed_size;
	}
	char str = buf;

	char *b = str + needed_size;
	*(--b) = '\0';
	char *last_comma = b;

	if (num == 0) {
	*(--b) = '0';
	} else {
	do {
	// The cast to fmt_uint_t is because num is positive and we want unsigned arithmetic
	int c = (fmt_uint_t)num % base;
	num = (fmt_uint_t)num / base;
	if (c >= 10) {
	c += base_char - 10;
	} else {
	c += '0';
	}
	*(--b) = c;
	if (comma && num != 0 && b > str && (last_comma - b) == 3) {
	*(--b) = comma;
	last_comma = b;
	}
	}
	while (b > str && num != 0);
	}
	if (prefix) {
	size_t prefix_len = strlen(prefix);
	char *p = b - prefix_len;
	if (p > str) {
	b = p;
	while (*prefix) {
	p++ = prefix++;
	}
	}
	}
	if (sign && b > str) {
	*(--b) = sign;
	}
	fmt_size = buf + needed_size - b - 1;

	return b;
	}

	#if MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_NONE

	int mp_obj_int_sign(mp_obj_t self_in) {
	mp_int_t val = mp_obj_get_int(self_in);
	if (val < 0) {
	return -1;
	} else if (val > 0) {
	return 1;
	} else {
	return 0;
	}
	}

	// This is called for operations on SMALL_INT that are not handled by mp_unary_op
	mp_obj_t mp_obj_int_unary_op(mp_unary_op_t op, mp_obj_t o_in) {
	return MP_OBJ_NULL; // op not supported
	}

	// This is called for operations on SMALL_INT that are not handled by mp_binary_op
	mp_obj_t mp_obj_int_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
	return mp_obj_int_binary_op_extra_cases(op, lhs_in, rhs_in);
	}

	// This is called only with strings whose value doesn't fit in SMALL_INT
	mp_obj_t mp_obj_new_int_from_str_len(const char **str, size_t len, bool neg, unsigned int base) {
	mp_raise_msg(&mp_type_OverflowError, "long int not supported in this build");
	return mp_const_none;
	}

	// This is called when an integer larger than a SMALL_INT is needed (although val might still fit in a SMALL_INT)
	mp_obj_t mp_obj_new_int_from_ll(long long val) {
	mp_raise_msg(&mp_type_OverflowError, "small int overflow");
	return mp_const_none;
	}

	// This is called when an integer larger than a SMALL_INT is needed (although val might still fit in a SMALL_INT)
	mp_obj_t mp_obj_new_int_from_ull(unsigned long long val) {
	mp_raise_msg(&mp_type_OverflowError, "small int overflow");
	return mp_const_none;
	}

	mp_obj_t mp_obj_new_int_from_uint(mp_uint_t value) {
	// SMALL_INT accepts only signed numbers, so make sure the input
	// value fits completely in the small-int positive range.
	if ((value & ~MP_SMALL_INT_POSITIVE_MASK) == 0) {
	return MP_OBJ_NEW_SMALL_INT(value);
	}
	mp_raise_msg(&mp_type_OverflowError, "small int overflow");
	return mp_const_none;
	}

	mp_obj_t mp_obj_new_int(mp_int_t value) {
	if (MP_SMALL_INT_FITS(value)) {
	return MP_OBJ_NEW_SMALL_INT(value);
	}
	mp_raise_msg(&mp_type_OverflowError, "small int overflow");
	return mp_const_none;
	}

	mp_int_t mp_obj_int_get_truncated(mp_const_obj_t self_in) {
	return MP_OBJ_SMALL_INT_VALUE(self_in);
	}

	mp_int_t mp_obj_int_get_checked(mp_const_obj_t self_in) {
	return MP_OBJ_SMALL_INT_VALUE(self_in);
	}

	#endif // MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_NONE

	// This dispatcher function is expected to be independent of the implementation of long int
	// It handles the extra cases for integer-like arithmetic
	mp_obj_t mp_obj_int_binary_op_extra_cases(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
	if (rhs_in == mp_const_false) {
	// false acts as 0
	return mp_binary_op(op, lhs_in, MP_OBJ_NEW_SMALL_INT(0));
	} else if (rhs_in == mp_const_true) {
	// true acts as 0
	return mp_binary_op(op, lhs_in, MP_OBJ_NEW_SMALL_INT(1));
	} else if (op == MP_BINARY_OP_MULTIPLY) {
	if (MP_OBJ_IS_STR(rhs_in) \|\| MP_OBJ_IS_TYPE(rhs_in, &mp_type_bytes) \|\| MP_OBJ_IS_TYPE(rhs_in, &mp_type_tuple) \|\| MP_OBJ_IS_TYPE(rhs_in, &mp_type_list)) {
	// multiply is commutative for these types, so delegate to them
	return mp_binary_op(op, rhs_in, lhs_in);
	}
	}
	return MP_OBJ_NULL; // op not supported
	}

	// this is a classmethod
	STATIC mp_obj_t int_from_bytes(size_t n_args, const mp_obj_t *args) {
	// TODO: Support signed param (assumes signed=False at the moment)
	(void)n_args;

	// get the buffer info
	mp_buffer_info_t bufinfo;
	mp_get_buffer_raise(args[1], &bufinfo, MP_BUFFER_READ);

	const byte* buf = (const byte*)bufinfo.buf;
	int delta = 1;
	if (args[2] == MP_OBJ_NEW_QSTR(MP_QSTR_little)) {
	buf += bufinfo.len - 1;
	delta = -1;
	}

	mp_uint_t value = 0;
	size_t len = bufinfo.len;
	for (; len--; buf += delta) {
	#if MICROPY_LONGINT_IMPL != MICROPY_LONGINT_IMPL_NONE
	if (value > (MP_SMALL_INT_MAX >> 8)) {
	// Result will overflow a small-int so construct a big-int
	return mp_obj_int_from_bytes_impl(args[2] != MP_OBJ_NEW_QSTR(MP_QSTR_little), bufinfo.len, bufinfo.buf);
	}
	#endif
	value = (value << 8) \| *buf;
	}
	return mp_obj_new_int_from_uint(value);
	}

	STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(int_from_bytes_fun_obj, 3, 4, int_from_bytes);
	STATIC MP_DEFINE_CONST_CLASSMETHOD_OBJ(int_from_bytes_obj, MP_ROM_PTR(&int_from_bytes_fun_obj));

	STATIC mp_obj_t int_to_bytes(size_t n_args, const mp_obj_t *args) {
	// TODO: Support signed param (assumes signed=False)
	(void)n_args;

	mp_int_t len = mp_obj_get_int(args[1]);
	if (len < 0) {
	mp_raise_ValueError(NULL);
	}
	bool big_endian = args[2] != MP_OBJ_NEW_QSTR(MP_QSTR_little);

	vstr_t vstr;
	vstr_init_len(&vstr, len);
	byte data = (byte)vstr.buf;
	memset(data, 0, len);

	#if MICROPY_LONGINT_IMPL != MICROPY_LONGINT_IMPL_NONE
	if (!MP_OBJ_IS_SMALL_INT(args[0])) {
	mp_obj_int_to_bytes_impl(args[0], big_endian, len, data);
	} else
	#endif
	{
	mp_int_t val = MP_OBJ_SMALL_INT_VALUE(args[0]);
	size_t l = MIN((size_t)len, sizeof(val));
	mp_binary_set_int(l, big_endian, data + (big_endian ? (len - l) : 0), val);
	}

	return mp_obj_new_str_from_vstr(&mp_type_bytes, &vstr);
	}
	STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(int_to_bytes_obj, 3, 4, int_to_bytes);

	STATIC const mp_rom_map_elem_t int_locals_dict_table[] = {
	{ MP_ROM_QSTR(MP_QSTR_from_bytes), MP_ROM_PTR(&int_from_bytes_obj) },
	{ MP_ROM_QSTR(MP_QSTR_to_bytes), MP_ROM_PTR(&int_to_bytes_obj) },
	};

	STATIC MP_DEFINE_CONST_DICT(int_locals_dict, int_locals_dict_table);

	const mp_obj_type_t mp_type_int = {
	{ &mp_type_type },
	.name = MP_QSTR_int,
	.print = mp_obj_int_print,
	.make_new = mp_obj_int_make_new,
	.unary_op = mp_obj_int_unary_op,
	.binary_op = mp_obj_int_binary_op,
	.locals_dict = (mp_obj_dict_t*)&int_locals_dict,
	};