circuitpython/py/objfloat.c
Paul Sokolovsky 9950865c39 py/objfloat: Fix binary ops with incompatible objects.
These are now returned as "operation not supported" instead of raising
TypeError. In particular, this fixes equality for float vs incompatible
types, which now properly results in False instead of exception. This
also paves the road to support reverse operation (e.g. __radd__) with
float objects.

This is achieved by introducing mp_obj_get_float_maybe(), similar to
existing mp_obj_get_int_maybe().
2017-09-02 23:05:24 +03:00

319 lines
11 KiB
C

/*
* 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 <stdio.h>
#include <string.h>
#include <assert.h>
#include "py/nlr.h"
#include "py/parsenum.h"
#include "py/runtime0.h"
#include "py/runtime.h"
#if MICROPY_PY_BUILTINS_FLOAT
#include <math.h>
#include "py/formatfloat.h"
#if MICROPY_OBJ_REPR != MICROPY_OBJ_REPR_C && MICROPY_OBJ_REPR != MICROPY_OBJ_REPR_D
// M_E and M_PI are not part of the math.h standard and may not be defined
#ifndef M_E
#define M_E (2.7182818284590452354)
#endif
#ifndef M_PI
#define M_PI (3.14159265358979323846)
#endif
typedef struct _mp_obj_float_t {
mp_obj_base_t base;
mp_float_t value;
} mp_obj_float_t;
const mp_obj_float_t mp_const_float_e_obj = {{&mp_type_float}, M_E};
const mp_obj_float_t mp_const_float_pi_obj = {{&mp_type_float}, M_PI};
#endif
#if MICROPY_FLOAT_HIGH_QUALITY_HASH
// must return actual integer value if it fits in mp_int_t
mp_int_t mp_float_hash(mp_float_t src) {
#if MICROPY_FLOAT_IMPL == MICROPY_FLOAT_IMPL_DOUBLE
typedef uint64_t mp_float_uint_t;
#elif MICROPY_FLOAT_IMPL == MICROPY_FLOAT_IMPL_FLOAT
typedef uint32_t mp_float_uint_t;
#endif
union {
mp_float_t f;
#if MP_ENDIANNESS_LITTLE
struct { mp_float_uint_t frc:MP_FLOAT_FRAC_BITS, exp:MP_FLOAT_EXP_BITS, sgn:1; } p;
#else
struct { mp_float_uint_t sgn:1, exp:MP_FLOAT_EXP_BITS, frc:MP_FLOAT_FRAC_BITS; } p;
#endif
mp_float_uint_t i;
} u = {.f = src};
mp_int_t val;
const int adj_exp = (int)u.p.exp - MP_FLOAT_EXP_BIAS;
if (adj_exp < 0) {
// value < 1; must be sure to handle 0.0 correctly (ie return 0)
val = u.i;
} else {
// if adj_exp is max then: u.p.frc==0 indicates inf, else NaN
// else: 1 <= value
mp_float_uint_t frc = u.p.frc | ((mp_float_uint_t)1 << MP_FLOAT_FRAC_BITS);
if (adj_exp <= MP_FLOAT_FRAC_BITS) {
// number may have a fraction; xor the integer part with the fractional part
val = (frc >> (MP_FLOAT_FRAC_BITS - adj_exp))
^ (frc & ((1 << (MP_FLOAT_FRAC_BITS - adj_exp)) - 1));
} else if ((unsigned int)adj_exp < BITS_PER_BYTE * sizeof(mp_int_t) - 1) {
// the number is a (big) whole integer and will fit in val's signed-width
val = (mp_int_t)frc << (adj_exp - MP_FLOAT_FRAC_BITS);
} else {
// integer part will overflow val's width so just use what bits we can
val = frc;
}
}
if (u.p.sgn) {
val = -val;
}
return val;
}
#endif
STATIC void float_print(const mp_print_t *print, mp_obj_t o_in, mp_print_kind_t kind) {
(void)kind;
mp_float_t o_val = mp_obj_float_get(o_in);
#if MICROPY_FLOAT_IMPL == MICROPY_FLOAT_IMPL_FLOAT
char buf[16];
#if MICROPY_OBJ_REPR == MICROPY_OBJ_REPR_C
const int precision = 6;
#else
const int precision = 7;
#endif
#else
char buf[32];
const int precision = 16;
#endif
mp_format_float(o_val, buf, sizeof(buf), 'g', precision, '\0');
mp_print_str(print, buf);
if (strchr(buf, '.') == NULL && strchr(buf, 'e') == NULL && strchr(buf, 'n') == NULL) {
// Python floats always have decimal point (unless inf or nan)
mp_print_str(print, ".0");
}
}
STATIC mp_obj_t float_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, 1, false);
switch (n_args) {
case 0:
return mp_obj_new_float(0);
case 1:
default:
if (MP_OBJ_IS_STR(args[0])) {
// a string, parse it
size_t l;
const char *s = mp_obj_str_get_data(args[0], &l);
return mp_parse_num_decimal(s, l, false, false, NULL);
} else if (mp_obj_is_float(args[0])) {
// a float, just return it
return args[0];
} else {
// something else, try to cast it to a float
return mp_obj_new_float(mp_obj_get_float(args[0]));
}
}
}
STATIC mp_obj_t float_unary_op(mp_unary_op_t op, mp_obj_t o_in) {
mp_float_t val = mp_obj_float_get(o_in);
switch (op) {
case MP_UNARY_OP_BOOL: return mp_obj_new_bool(val != 0);
case MP_UNARY_OP_HASH: return MP_OBJ_NEW_SMALL_INT(mp_float_hash(val));
case MP_UNARY_OP_POSITIVE: return o_in;
case MP_UNARY_OP_NEGATIVE: return mp_obj_new_float(-val);
default: return MP_OBJ_NULL; // op not supported
}
}
STATIC mp_obj_t float_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
mp_float_t lhs_val = mp_obj_float_get(lhs_in);
#if MICROPY_PY_BUILTINS_COMPLEX
if (MP_OBJ_IS_TYPE(rhs_in, &mp_type_complex)) {
return mp_obj_complex_binary_op(op, lhs_val, 0, rhs_in);
} else
#endif
{
return mp_obj_float_binary_op(op, lhs_val, rhs_in);
}
}
const mp_obj_type_t mp_type_float = {
{ &mp_type_type },
.name = MP_QSTR_float,
.print = float_print,
.make_new = float_make_new,
.unary_op = float_unary_op,
.binary_op = float_binary_op,
};
#if MICROPY_OBJ_REPR != MICROPY_OBJ_REPR_C && MICROPY_OBJ_REPR != MICROPY_OBJ_REPR_D
mp_obj_t mp_obj_new_float(mp_float_t value) {
mp_obj_float_t *o = m_new(mp_obj_float_t, 1);
o->base.type = &mp_type_float;
o->value = value;
return MP_OBJ_FROM_PTR(o);
}
mp_float_t mp_obj_float_get(mp_obj_t self_in) {
assert(mp_obj_is_float(self_in));
mp_obj_float_t *self = MP_OBJ_TO_PTR(self_in);
return self->value;
}
#endif
STATIC void mp_obj_float_divmod(mp_float_t *x, mp_float_t *y) {
// logic here follows that of CPython
// https://docs.python.org/3/reference/expressions.html#binary-arithmetic-operations
// x == (x//y)*y + (x%y)
// divmod(x, y) == (x//y, x%y)
mp_float_t mod = MICROPY_FLOAT_C_FUN(fmod)(*x, *y);
mp_float_t div = (*x - mod) / *y;
// Python specs require that mod has same sign as second operand
if (mod == 0.0) {
mod = MICROPY_FLOAT_C_FUN(copysign)(0.0, *y);
} else {
if ((mod < 0.0) != (*y < 0.0)) {
mod += *y;
div -= 1.0;
}
}
mp_float_t floordiv;
if (div == 0.0) {
// if division is zero, take the correct sign of zero
floordiv = MICROPY_FLOAT_C_FUN(copysign)(0.0, *x / *y);
} else {
// Python specs require that x == (x//y)*y + (x%y)
floordiv = MICROPY_FLOAT_C_FUN(floor)(div);
if (div - floordiv > 0.5) {
floordiv += 1.0;
}
}
// return results
*x = floordiv;
*y = mod;
}
mp_obj_t mp_obj_float_binary_op(mp_binary_op_t op, mp_float_t lhs_val, mp_obj_t rhs_in) {
mp_float_t rhs_val;
if (!mp_obj_get_float_maybe(rhs_in, &rhs_val)) {
return MP_OBJ_NULL; // op not supported
}
switch (op) {
case MP_BINARY_OP_ADD:
case MP_BINARY_OP_INPLACE_ADD: lhs_val += rhs_val; break;
case MP_BINARY_OP_SUBTRACT:
case MP_BINARY_OP_INPLACE_SUBTRACT: lhs_val -= rhs_val; break;
case MP_BINARY_OP_MULTIPLY:
case MP_BINARY_OP_INPLACE_MULTIPLY: lhs_val *= rhs_val; break;
case MP_BINARY_OP_FLOOR_DIVIDE:
case MP_BINARY_OP_INPLACE_FLOOR_DIVIDE:
if (rhs_val == 0) {
zero_division_error:
mp_raise_msg(&mp_type_ZeroDivisionError, "division by zero");
}
// Python specs require that x == (x//y)*y + (x%y) so we must
// call divmod to compute the correct floor division, which
// returns the floor divide in lhs_val.
mp_obj_float_divmod(&lhs_val, &rhs_val);
break;
case MP_BINARY_OP_TRUE_DIVIDE:
case MP_BINARY_OP_INPLACE_TRUE_DIVIDE:
if (rhs_val == 0) {
goto zero_division_error;
}
lhs_val /= rhs_val;
break;
case MP_BINARY_OP_MODULO:
case MP_BINARY_OP_INPLACE_MODULO:
if (rhs_val == 0) {
goto zero_division_error;
}
lhs_val = MICROPY_FLOAT_C_FUN(fmod)(lhs_val, rhs_val);
// Python specs require that mod has same sign as second operand
if (lhs_val == 0.0) {
lhs_val = MICROPY_FLOAT_C_FUN(copysign)(0.0, rhs_val);
} else {
if ((lhs_val < 0.0) != (rhs_val < 0.0)) {
lhs_val += rhs_val;
}
}
break;
case MP_BINARY_OP_POWER:
case MP_BINARY_OP_INPLACE_POWER:
if (lhs_val == 0 && rhs_val < 0) {
goto zero_division_error;
}
lhs_val = MICROPY_FLOAT_C_FUN(pow)(lhs_val, rhs_val);
break;
case MP_BINARY_OP_DIVMOD: {
if (rhs_val == 0) {
goto zero_division_error;
}
mp_obj_float_divmod(&lhs_val, &rhs_val);
mp_obj_t tuple[2] = {
mp_obj_new_float(lhs_val),
mp_obj_new_float(rhs_val),
};
return mp_obj_new_tuple(2, tuple);
}
case MP_BINARY_OP_LESS: return mp_obj_new_bool(lhs_val < rhs_val);
case MP_BINARY_OP_MORE: return mp_obj_new_bool(lhs_val > rhs_val);
case MP_BINARY_OP_EQUAL: return mp_obj_new_bool(lhs_val == rhs_val);
case MP_BINARY_OP_LESS_EQUAL: return mp_obj_new_bool(lhs_val <= rhs_val);
case MP_BINARY_OP_MORE_EQUAL: return mp_obj_new_bool(lhs_val >= rhs_val);
default:
return MP_OBJ_NULL; // op not supported
}
return mp_obj_new_float(lhs_val);
}
#endif // MICROPY_PY_BUILTINS_FLOAT