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/*
* Copyright (C) 2021 Tomasz Kramkowski <tk@the-tk.com>
* SPDX-License-Identifier: MIT
*/
#include <math.h>
#include <stdbool.h>
#include "common.h"
#include "ieee754b.h"
#define GEN_IEEE754B_DESER(type, total, nexp, nfrac) \
type ieee754b##total##_deserialise(uintmax_t b) \
{ \
bool isneg; \
int exp; \
type n; \
\
isneg = (b >> (total - 1)) & 0x1; \
exp = (b >> nfrac) & BITMASK(nexp); \
n = b & BITMASK(nfrac); \
\
if (exp == BITMASK(nexp)) { \
if (n) { \
return NAN; \
} else { \
return isneg ? -INFINITY : INFINITY; \
} \
} else if (exp == 0) { \
if (n == 0) \
return isneg ? -0.0 : 0.0; \
exp = -(int)(BITMASK(nexp) / 2 - 1); \
} else { \
n += 0x1p##nfrac##f; \
exp -= BITMASK(nexp) / 2; \
} \
\
n = ldexpf(n, exp - nfrac); \
\
return isneg ? -n : n; \
}
GEN_IEEE754B_DESER(float, 32, 8, 23)
GEN_IEEE754B_DESER(double, 64, 11, 52)
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