#include "PosixSource.h"
#include "Rts.h"
+#include "StgPrimFloat.h"
+
#include <math.h>
+#include <float.h>
+
+#define IEEE_FLOATING_POINT 1
/*
* Encoding and decoding Doubles. Code based on the HBC code
}
}
-union stg_ieee754_flt
-{
- float f;
- struct {
-
-#if WORDS_BIGENDIAN
- unsigned int negative:1;
- unsigned int exponent:8;
- unsigned int mantissa:23;
-#else
- unsigned int mantissa:23;
- unsigned int exponent:8;
- unsigned int negative:1;
-#endif
- } ieee;
- struct {
-
-#if WORDS_BIGENDIAN
- unsigned int negative:1;
- unsigned int exponent:8;
- unsigned int quiet_nan:1;
- unsigned int mantissa:22;
-#else
- unsigned int mantissa:22;
- unsigned int quiet_nan:1;
- unsigned int exponent:8;
- unsigned int negative:1;
-#endif
- } ieee_nan;
-};
-
-/*
-
- To recap, here's the representation of a double precision
- IEEE floating point number:
-
- sign 63 sign bit (0==positive, 1==negative)
- exponent 62-52 exponent (biased by 1023)
- fraction 51-0 fraction (bits to right of binary point)
-*/
-
-union stg_ieee754_dbl
-{
- double d;
- struct {
-
-#if WORDS_BIGENDIAN
- unsigned int negative:1;
- unsigned int exponent:11;
- unsigned int mantissa0:20;
- unsigned int mantissa1:32;
-#else
-#if FLOAT_WORDS_BIGENDIAN
- unsigned int mantissa0:20;
- unsigned int exponent:11;
- unsigned int negative:1;
- unsigned int mantissa1:32;
-#else
- unsigned int mantissa1:32;
- unsigned int mantissa0:20;
- unsigned int exponent:11;
- unsigned int negative:1;
-#endif
-#endif
- } ieee;
- /* This format makes it easier to see if a NaN is a signalling NaN. */
- struct {
-
-#if WORDS_BIGENDIAN
- unsigned int negative:1;
- unsigned int exponent:11;
- unsigned int quiet_nan:1;
- unsigned int mantissa0:19;
- unsigned int mantissa1:32;
-#else
-#if FLOAT_WORDS_BIGENDIAN
- unsigned int mantissa0:19;
- unsigned int quiet_nan:1;
- unsigned int exponent:11;
- unsigned int negative:1;
- unsigned int mantissa1:32;
-#else
- unsigned int mantissa1:32;
- unsigned int mantissa0:19;
- unsigned int quiet_nan:1;
- unsigned int exponent:11;
- unsigned int negative:1;
-#endif
-#endif
- } ieee_nan;
-};
-
-/*
- * Predicates for testing for extreme IEEE fp values. Used
- * by the bytecode evaluator and the Prelude.
- *
- */
-
-/* In case you don't suppport IEEE, you'll just get dummy defs.. */
-#ifdef IEEE_FLOATING_POINT
-
-StgInt
-isDoubleNaN(StgDouble d)
-{
- union stg_ieee754_dbl u;
-
- u.d = d;
-
- return (
- u.ieee.exponent == 2047 /* 2^11 - 1 */ && /* Is the exponent all ones? */
- (u.ieee.mantissa0 != 0 || u.ieee.mantissa1 != 0)
- /* and the mantissa non-zero? */
- );
-}
-
-StgInt
-isDoubleInfinite(StgDouble d)
-{
- union stg_ieee754_dbl u;
-
- u.d = d;
-
- /* Inf iff exponent is all ones, mantissa all zeros */
- return (
- u.ieee.exponent == 2047 /* 2^11 - 1 */ &&
- u.ieee.mantissa0 == 0 &&
- u.ieee.mantissa1 == 0
- );
-}
-
-StgInt
-isDoubleDenormalized(StgDouble d)
-{
- union stg_ieee754_dbl u;
-
- u.d = d;
-
- /* A (single/double/quad) precision floating point number
- is denormalised iff:
- - exponent is zero
- - mantissa is non-zero.
- - (don't care about setting of sign bit.)
-
- */
- return (
- u.ieee.exponent == 0 &&
- (u.ieee.mantissa0 != 0 ||
- u.ieee.mantissa1 != 0)
- );
-
-}
-
-StgInt
-isDoubleNegativeZero(StgDouble d)
-{
- union stg_ieee754_dbl u;
-
- u.d = d;
- /* sign (bit 63) set (only) => negative zero */
-
- return (
- u.ieee.negative == 1 &&
- u.ieee.exponent == 0 &&
- u.ieee.mantissa0 == 0 &&
- u.ieee.mantissa1 == 0);
-}
-
-/* Same tests, this time for StgFloats. */
-
-/*
- To recap, here's the representation of a single precision
- IEEE floating point number:
-
- sign 31 sign bit (0 == positive, 1 == negative)
- exponent 30-23 exponent (biased by 127)
- fraction 22-0 fraction (bits to right of binary point)
-*/
-
-
-StgInt
-isFloatNaN(StgFloat f)
-{
- union stg_ieee754_flt u;
- u.f = f;
-
- /* Floating point NaN iff exponent is all ones, mantissa is
- non-zero (but see below.) */
- return (
- u.ieee.exponent == 255 /* 2^8 - 1 */ &&
- u.ieee.mantissa != 0);
-}
-
-StgInt
-isFloatInfinite(StgFloat f)
-{
- union stg_ieee754_flt u;
- u.f = f;
-
- /* A float is Inf iff exponent is max (all ones),
- and mantissa is min(all zeros.) */
- return (
- u.ieee.exponent == 255 /* 2^8 - 1 */ &&
- u.ieee.mantissa == 0);
-}
-
-StgInt
-isFloatDenormalized(StgFloat f)
-{
- union stg_ieee754_flt u;
- u.f = f;
-
- /* A (single/double/quad) precision floating point number
- is denormalised iff:
- - exponent is zero
- - mantissa is non-zero.
- - (don't care about setting of sign bit.)
-
- */
- return (
- u.ieee.exponent == 0 &&
- u.ieee.mantissa != 0);
-}
-
-StgInt
-isFloatNegativeZero(StgFloat f)
-{
- union stg_ieee754_flt u;
- u.f = f;
-
- /* sign (bit 31) set (only) => negative zero */
- return (
- u.ieee.negative &&
- u.ieee.exponent == 0 &&
- u.ieee.mantissa == 0);
-}
-
-#else /* ! IEEE_FLOATING_POINT */
-
-/* Dummy definitions of predicates - they all return false */
-StgInt isDoubleNaN(d) StgDouble d; { return 0; }
-StgInt isDoubleInfinite(d) StgDouble d; { return 0; }
-StgInt isDoubleDenormalized(d) StgDouble d; { return 0; }
-StgInt isDoubleNegativeZero(d) StgDouble d; { return 0; }
-StgInt isFloatNaN(f) StgFloat f; { return 0; }
-StgInt isFloatInfinite(f) StgFloat f; { return 0; }
-StgInt isFloatDenormalized(f) StgFloat f; { return 0; }
-StgInt isFloatNegativeZero(f) StgFloat f; { return 0; }
-
-#endif /* ! IEEE_FLOATING_POINT */
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