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#include "platform.h"
#if HAS_FPCLASSIFY
Int Real32_class (Real32 f) {
return fpclassify (f);
}
#elif HAS_FPCLASSIFY32
Int Real32_class (Real32 f) {
return fpclassify32 (f);
}
#else
/* masks for word 0 */
#define EXPONENT_MASK32 0x7F800000
#define MANTISSA_MASK32 0x007FFFFF
#define SIGNBIT_MASK32 0x80000000
#define MANTISSA_HIGHBIT_MASK32 0x00400000
Int Real32_class (Real32 f) {
uint word0;
int res;
word0 = ((uint *)&f)[0]; /* this generates a gcc warning */
if ((word0 & EXPONENT_MASK32) == EXPONENT_MASK32) {
if (word0 & MANTISSA_MASK32)
res = FP_NAN;
else
res = FP_INFINITE;
} else if (word0 & EXPONENT_MASK32)
res = FP_NORMAL;
else if (word0 & MANTISSA_MASK32)
res = FP_SUBNORMAL;
else
res = FP_ZERO;
return res;
}
#endif
#if HAS_FPCLASSIFY
Int Real64_class (Real64 d) {
return fpclassify (d);
}
#elif HAS_FPCLASSIFY64
Int Real64_class (Real64 d) {
return fpclassify64 (d);
}
#else
#if (defined __i386__)
/* This code assumes IEEE 754/854 and little endian.
*
* In memory, the 64 bits of a double are layed out as follows.
*
* d[0] bits 7-0 of mantissa
* d[1] bits 15-8 of mantissa
* d[2] bits 23-16 of mantissa
* d[3] bits 31-24 of mantissa
* d[4] bits 39-32 of mantissa
* d[5] bits 47-40 of mantissa
* d[6] bits 3-0 of exponent
* bits 51-48 of mantissa
* d[7] sign bit
* bits 10-4 of exponent
*
*
* In memory, the 32 bits of a float are layed out as follows.
*
* d[0] bits 7-0 of mantissa
* d[1] bits 15-8 of mantissa
* d[2] bit 0 of exponent
* bits 22-16 of mantissa
* d[7] sign bit
* bits 7-2 of exponent
*/
/* masks for word 1 */
#define EXPONENT_MASK64 0x7FF00000
#define MANTISSA_MASK64 0x000FFFFF
#define SIGNBIT_MASK64 0x80000000
#define MANTISSA_HIGHBIT_MASK64 0x00080000
Int Real64_class (Real64 d) {
Word word0, word1;
Int res;
word0 = ((Word *)&d)[0];
word1 = ((Word *)&d)[1];
if ((word1 & EXPONENT_MASK64) == EXPONENT_MASK64) {
if (word0 or (word1 & MANTISSA_MASK64))
res = FP_NAN;
else
res = FP_INFINITE;
} else if (word1 & EXPONENT_MASK64)
res = FP_NORMAL;
else if (word0 or (word1 & MANTISSA_MASK64))
res = FP_SUBNORMAL;
else
res = FP_ZERO;
return res;
}
#else
#error Real64_class not implemented
#endif
#endif
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