shithub: femtolisp

ref: e547019e603e4c3bc72117dd653662636a5cae29
dir: /ieee754.h/

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#pragma once

union ieee754_float {
	float f;

	struct {
#if BYTE_ORDER == BIG_ENDIAN
	unsigned int negative:1;
	unsigned int exponent:8;
	unsigned int mantissa:23;
#elif BYTE_ORDER == LITTLE_ENDIAN
	unsigned int mantissa:23;
	unsigned int exponent:8;
	unsigned int negative:1;
#else
#error which endian?
#endif
	}ieee;
};

#define IEEE754_FLOAT_BIAS 0x7f

union ieee754_double {
	double d;

	struct {
#if BYTE_ORDER == BIG_ENDIAN
	unsigned int negative:1;
	unsigned int exponent:11;
	unsigned int mantissa0:20;
	unsigned int mantissa1:32;
#else
	unsigned int mantissa1:32;
	unsigned int mantissa0:20;
	unsigned int exponent:11;
	unsigned int negative:1;
#endif
	}ieee;
};

#define IEEE754_DOUBLE_BIAS 0x3ff

union ieee854_long_double {
	long double d;

	struct {
#if BYTE_ORDER == BIG_ENDIAN
	unsigned int negative:1;
	unsigned int exponent:15;
	unsigned int empty:16;
	unsigned int mantissa0:32;
	unsigned int mantissa1:32;
#else
	unsigned int mantissa1:32;
	unsigned int mantissa0:32;
	unsigned int exponent:15;
	unsigned int negative:1;
	unsigned int empty:16;
#endif
	}ieee;
};

#define IEEE854_LONG_DOUBLE_BIAS 0x3fff