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-rw-r--r--libraries/integer-gmp/cbits/float.c249
1 files changed, 0 insertions, 249 deletions
diff --git a/libraries/integer-gmp/cbits/float.c b/libraries/integer-gmp/cbits/float.c
deleted file mode 100644
index 73a89f577a..0000000000
--- a/libraries/integer-gmp/cbits/float.c
+++ /dev/null
@@ -1,249 +0,0 @@
-/* -----------------------------------------------------------------------------
- *
- * (c) Lennart Augustsson
- * (c) The GHC Team, 1998-2000
- *
- * Support for floating-point <-> gmp integer primitives
- *
- * ---------------------------------------------------------------------------*/
-
-/* TODO: do we need PosixSource.h ? it lives in rts/ not public includes/ */
-/* #include "PosixSource.h" */
-#include "Rts.h"
-#include "gmp.h"
-#include "GmpDerivedConstants.h"
-
-#include <math.h>
-
-#define IEEE_FLOATING_POINT 1
-
-/*
- * Encoding and decoding Doubles. Code based on the HBC code
- * (lib/fltcode.c).
- */
-
-#define SIZEOF_LIMB_T SIZEOF_MP_LIMB_T
-
-#if SIZEOF_LIMB_T == 4
-#define GMP_BASE 4294967296.0
-#define LIMBBITS_LOG_2 5
-#elif SIZEOF_LIMB_T == 8
-#define GMP_BASE 18446744073709551616.0
-#define LIMBBITS_LOG_2 6
-#else
-#error Cannot cope with SIZEOF_LIMB_T -- please add definition of GMP_BASE
-#endif
-
-#define DNBIGIT ((SIZEOF_DOUBLE+SIZEOF_LIMB_T-1)/SIZEOF_LIMB_T)
-#define FNBIGIT ((SIZEOF_FLOAT +SIZEOF_LIMB_T-1)/SIZEOF_LIMB_T)
-
-#if IEEE_FLOATING_POINT
-#define MY_DMINEXP ((DBL_MIN_EXP) - (DBL_MANT_DIG) - 1)
-/* DMINEXP is defined in values.h on Linux (for example) */
-#define DHIGHBIT 0x00100000
-#define DMSBIT 0x80000000
-
-#define MY_FMINEXP ((FLT_MIN_EXP) - (FLT_MANT_DIG) - 1)
-#define FHIGHBIT 0x00800000
-#define FMSBIT 0x80000000
-#endif
-
-#if defined(WORDS_BIGENDIAN) || defined(FLOAT_WORDS_BIGENDIAN)
-#define L 1
-#define H 0
-#else
-#define L 0
-#define H 1
-#endif
-
-#define __abs(a) (( (a) >= 0 ) ? (a) : (-(a)))
-
-StgDouble
-integer_cbits_encodeDouble (I_ size, StgByteArray ba, I_ e) /* result = s * 2^e */
-{
- StgDouble r;
- const mp_limb_t *const arr = (const mp_limb_t *)ba;
- I_ i;
-
- /* Convert MP_INT to a double; knows a lot about internal rep! */
- i = __abs(size)-1;
- if ((i < 15) || (e >= 0)) /* overflows only if the final result does */
- {
- /* This would cause overflow if a large MP_INT is passed, even if the
- * exponent would scale it back into range, so we do it only when it's safe. */
- for(r = 0.0; i >= 0; i--)
- r = (r * GMP_BASE) + arr[i];
-
- } else { /* possibly more than 1024 bits in the MP_INT, but gets scaled down */
-
- /* Find the first nonzero limb; normally it would be the first */
- r = 0.0;
- while((i >= 0) && (r == 0.0))
- {
- r = arr[i--];
- }
- if (i >= 0)
- r = (r * GMP_BASE) + arr[i];
-#if SIZEOF_LIMB_T < 8
- if (i > 0)
- r = (r * GMP_BASE) + arr[--i];
-#endif
- /* Now we have at least the 65 leading bits of the MP_INT or all of it.
- * Any further bits would be rounded down, so from now on everything is
- * multiplication by powers of 2.
- * If i is positive, arr contains i limbs we haven't looked at yet, so
- * adjust the exponent by i*8*SIZEOF_LIMB_T. Unfortunately, we must
- * beware of overflow, so we can't simply add this to e. */
- if (i > 0)
- {
- /* first add the number of whole limbs that would be cancelled */
- i = i + e / (8 * SIZEOF_LIMB_T);
- /* check for overflow */
- if ((i > 0) && ((i >> (8*sizeof(I_) - 1 - LIMBBITS_LOG_2)) > 0))
- {
- /* overflow, give e a large dummy value */
- e = 2147483647;
- } else {
- /* no overflow, get the exact value */
- e = i * (8 * SIZEOF_LIMB_T) + (e % (8 * SIZEOF_LIMB_T));
- }
- }
- }
-
- /* Now raise to the exponent */
- if ( r != 0.0 ) /* Lennart suggests this avoids a bug in MIPS's ldexp */
- r = ldexp(r, e);
-
- /* sign is encoded in the size */
- if (size < 0)
- r = -r;
-
- return r;
-}
-
-StgFloat
-integer_cbits_encodeFloat (I_ size, StgByteArray ba, I_ e) /* result = s * 2^e */
-{
- StgFloat r;
- const mp_limb_t *arr = (const mp_limb_t *)ba;
- I_ i;
-
- /* Convert MP_INT to a float; knows a lot about internal rep! */
- i = __abs(size)-1;
- /* just in case StgFloat is a double, check sizes */
-#if SIZEOF_FLOAT == 4
- if ((i < 2) || (e >= 0))
-#else
- if ((i < 15) || (e >= 0))
-#endif
- {
- for(r = 0.0; i >= 0; i--)
- r = (r * GMP_BASE) + arr[i];
- } else {
-
- /* Find the first nonzero limb; normally it would be the first */
- r = 0.0;
- while((i >= 0) && (r == 0.0))
- {
- r = arr[i--];
- }
- if (i >= 0)
- r = (r * GMP_BASE) + arr[i];
-#if (SIZEOF_LIMB_T < 8) && (SIZEOF_FLOAT > 4)
- if (i > 0)
- r = (r * GMP_BASE) + arr[--i];
-#endif
- /* Now we have enough leading bits of the MP_INT.
- * Any further bits would be rounded down, so from now on everything is
- * multiplication by powers of 2.
- * If i is positive, arr contains i limbs we haven't looked at yet, so
- * adjust the exponent by i*8*SIZEOF_LIMB_T. Unfortunately, we must
- * beware of overflow, so we can't simply add this to e. */
- if (i > 0)
- {
- /* first add the number of whole limbs that would be cancelled */
- i = i + e / (8 * SIZEOF_LIMB_T);
- /* check for overflow */
- if ((i > 0) && ((i >> (8*sizeof(I_) - 1 - LIMBBITS_LOG_2)) > 0))
- {
- /* overflow, give e a large dummy value */
- e = 2147483647;
- } else {
- /* no overflow, get the exact value */
- e = i * (8 * SIZEOF_LIMB_T) + (e % (8 * SIZEOF_LIMB_T));
- }
- }
- }
-
- /* Now raise to the exponent */
- if ( r != 0.0 ) /* Lennart suggests this avoids a bug in MIPS's ldexp */
- r = ldexp(r, e);
-
- /* sign is encoded in the size */
- if (size < 0)
- r = -r;
-
- return r;
-}
-
-/* This only supports IEEE floating point */
-
-void
-integer_cbits_decodeDouble (MP_INT *man, I_ *exp, StgDouble dbl)
-{
- /* Do some bit fiddling on IEEE */
- unsigned int low, high; /* assuming 32 bit ints */
- int sign, iexp;
- union { double d; unsigned int i[2]; } u; /* assuming 32 bit ints, 64 bit double */
-
- ASSERT(sizeof(unsigned int ) == 4 );
- ASSERT(sizeof(dbl ) == SIZEOF_DOUBLE);
- ASSERT(sizeof(man->_mp_d[0]) == SIZEOF_LIMB_T);
- ASSERT(DNBIGIT*SIZEOF_LIMB_T >= SIZEOF_DOUBLE);
-
- u.d = dbl; /* grab chunks of the double */
- low = u.i[L];
- high = u.i[H];
-
- /* we know the MP_INT* passed in has size zero, so we realloc
- no matter what.
- */
- man->_mp_alloc = DNBIGIT;
-
- if (low == 0 && (high & ~DMSBIT) == 0) {
- man->_mp_size = 0;
- *exp = 0L;
- } else {
- man->_mp_size = DNBIGIT;
- iexp = ((high >> 20) & 0x7ff) + MY_DMINEXP;
- sign = high;
-
- high &= DHIGHBIT-1;
- if (iexp != MY_DMINEXP) /* don't add hidden bit to denorms */
- high |= DHIGHBIT;
- else {
- iexp++;
- /* A denorm, normalize the mantissa */
- while (! (high & DHIGHBIT)) {
- high <<= 1;
- if (low & DMSBIT)
- high++;
- low <<= 1;
- iexp--;
- }
- }
- *exp = (I_) iexp;
-#if DNBIGIT == 2
- man->_mp_d[0] = (mp_limb_t)low;
- man->_mp_d[1] = (mp_limb_t)high;
-#else
-#if DNBIGIT == 1
- man->_mp_d[0] = ((mp_limb_t)high) << 32 | (mp_limb_t)low;
-#else
-#error Cannot cope with DNBIGIT
-#endif
-#endif
- if (sign < 0)
- man->_mp_size = -man->_mp_size;
- }
-}
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