ocaml/runtime/floats.c

1050 lines
27 KiB
C

/**************************************************************************/
/* */
/* OCaml */
/* */
/* Xavier Leroy, projet Cristal, INRIA Rocquencourt */
/* */
/* Copyright 1996 Institut National de Recherche en Informatique et */
/* en Automatique. */
/* */
/* All rights reserved. This file is distributed under the terms of */
/* the GNU Lesser General Public License version 2.1, with the */
/* special exception on linking described in the file LICENSE. */
/* */
/**************************************************************************/
#define CAML_INTERNALS
/* The interface of this file is in "caml/mlvalues.h" and "caml/alloc.h" */
/* Needed for uselocale */
#define _XOPEN_SOURCE 700
/* Needed for strtod_l */
#define _GNU_SOURCE
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <float.h>
#include <limits.h>
#include "caml/alloc.h"
#include "caml/fail.h"
#include "caml/memory.h"
#include "caml/mlvalues.h"
#include "caml/misc.h"
#include "caml/reverse.h"
#include "caml/stacks.h"
#if defined(HAS_LOCALE) || defined(__MINGW32__)
#if defined(HAS_LOCALE_H) || defined(__MINGW32__)
#include <locale.h>
#endif
#if defined(HAS_XLOCALE_H)
#include <xlocale.h>
#endif
#if defined(_MSC_VER)
#ifndef locale_t
#define locale_t _locale_t
#endif
#ifndef freelocale
#define freelocale _free_locale
#endif
#ifndef strtod_l
#define strtod_l _strtod_l
#endif
#endif
#endif /* defined(HAS_LOCALE) */
#ifdef _MSC_VER
#include <float.h>
#ifndef isnan
#define isnan _isnan
#endif
#ifndef isfinite
#define isfinite _finite
#endif
#ifndef nextafter
#define nextafter _nextafter
#endif
#endif
#ifdef ARCH_ALIGN_DOUBLE
CAMLexport double caml_Double_val(value val)
{
union { value v[2]; double d; } buffer;
CAMLassert(sizeof(double) == 2 * sizeof(value));
buffer.v[0] = Field(val, 0);
buffer.v[1] = Field(val, 1);
return buffer.d;
}
CAMLexport void caml_Store_double_val(value val, double dbl)
{
union { value v[2]; double d; } buffer;
CAMLassert(sizeof(double) == 2 * sizeof(value));
buffer.d = dbl;
Field(val, 0) = buffer.v[0];
Field(val, 1) = buffer.v[1];
}
#endif
/*
OCaml runtime itself doesn't call setlocale, i.e. it is using
standard "C" locale by default, but it is possible that
third-party code loaded into process does.
*/
#ifdef HAS_LOCALE
locale_t caml_locale = (locale_t)0;
#endif
#if defined(_MSC_VER) || defined(__MINGW32__)
/* there is no analogue to uselocale in MSVC so just set locale for thread */
#define USE_LOCALE setlocale(LC_NUMERIC,"C")
#define RESTORE_LOCALE do {} while(0)
#elif defined(HAS_LOCALE)
#define USE_LOCALE locale_t saved_locale = uselocale(caml_locale)
#define RESTORE_LOCALE uselocale(saved_locale)
#else
#define USE_LOCALE do {} while(0)
#define RESTORE_LOCALE do {} while(0)
#endif
void caml_init_locale(void)
{
#if defined(_MSC_VER) || defined(__MINGW32__)
_configthreadlocale(_ENABLE_PER_THREAD_LOCALE);
#endif
#ifdef HAS_LOCALE
if ((locale_t)0 == caml_locale)
{
#if defined(_MSC_VER)
caml_locale = _create_locale(LC_NUMERIC, "C");
#else
caml_locale = newlocale(LC_NUMERIC_MASK,"C",(locale_t)0);
#endif
}
#endif
}
void caml_free_locale(void)
{
#ifdef HAS_LOCALE
if ((locale_t)0 != caml_locale) freelocale(caml_locale);
caml_locale = (locale_t)0;
#endif
}
CAMLexport value caml_copy_double(double d)
{
value res;
#define Setup_for_gc
#define Restore_after_gc
Alloc_small(res, Double_wosize, Double_tag);
#undef Setup_for_gc
#undef Restore_after_gc
Store_double_val(res, d);
return res;
}
#ifndef FLAT_FLOAT_ARRAY
CAMLexport void caml_Store_double_array_field(value val, mlsize_t i, double dbl)
{
CAMLparam1 (val);
value d = caml_copy_double (dbl);
CAMLassert (Tag_val (val) != Double_array_tag);
caml_modify (&Field(val, i), d);
CAMLreturn0;
}
#endif /* ! FLAT_FLOAT_ARRAY */
CAMLprim value caml_format_float(value fmt, value arg)
{
value res;
double d = Double_val(arg);
#ifdef HAS_BROKEN_PRINTF
if (isfinite(d)) {
#endif
USE_LOCALE;
res = caml_alloc_sprintf(String_val(fmt), d);
RESTORE_LOCALE;
#ifdef HAS_BROKEN_PRINTF
} else {
if (isnan(d)) {
res = caml_copy_string("nan");
} else {
if (d > 0)
res = caml_copy_string("inf");
else
res = caml_copy_string("-inf");
}
}
#endif
return res;
}
CAMLprim value caml_hexstring_of_float(value arg, value vprec, value vstyle)
{
union { uint64_t i; double d; } u;
int sign, exp;
uint64_t m;
char buffer[64];
char * buf, * p;
intnat prec;
int d;
value res;
/* Allocate output buffer */
prec = Long_val(vprec);
/* 12 chars for sign, 0x, decimal point, exponent */
buf = (prec + 12 <= 64 ? buffer : caml_stat_alloc(prec + 12));
/* Extract sign, mantissa, and exponent */
u.d = Double_val(arg);
sign = u.i >> 63;
exp = (u.i >> 52) & 0x7FF;
m = u.i & (((uint64_t) 1 << 52) - 1);
/* Put sign */
p = buf;
if (sign) {
*p++ = '-';
} else {
switch (Int_val(vstyle)) {
case '+': *p++ = '+'; break;
case ' ': *p++ = ' '; break;
}
}
/* Treat special cases */
if (exp == 0x7FF) {
char * txt;
if (m == 0) txt = "infinity"; else txt = "nan";
memcpy(p, txt, strlen(txt));
p[strlen(txt)] = 0;
res = caml_copy_string(buf);
} else {
/* Output "0x" prefix */
*p++ = '0'; *p++ = 'x';
/* Normalize exponent and mantissa */
if (exp == 0) {
if (m != 0) exp = -1022; /* denormal */
} else {
exp = exp - 1023;
m = m | ((uint64_t) 1 << 52);
}
/* If a precision is given, and is small, round mantissa accordingly */
prec = Long_val(vprec);
if (prec >= 0 && prec < 13) {
int i = 52 - prec * 4;
uint64_t unit = (uint64_t) 1 << i;
uint64_t half = unit >> 1;
uint64_t mask = unit - 1;
uint64_t frac = m & mask;
m = m & ~mask;
/* Round to nearest, ties to even */
if (frac > half || (frac == half && (m & unit) != 0)) {
m += unit;
}
}
/* Leading digit */
d = m >> 52;
*p++ = (d < 10 ? d + '0' : d - 10 + 'a');
m = (m << 4) & (((uint64_t) 1 << 56) - 1);
/* Fractional digits. If a precision is given, print that number of
digits. Otherwise, print as many digits as needed to represent
the mantissa exactly. */
if (prec >= 0 ? prec > 0 : m != 0) {
*p++ = '.';
while (prec >= 0 ? prec > 0 : m != 0) {
d = m >> 52;
*p++ = (d < 10 ? d + '0' : d - 10 + 'a');
m = (m << 4) & (((uint64_t) 1 << 56) - 1);
prec--;
}
}
*p = 0;
/* Add exponent */
res = caml_alloc_sprintf("%sp%+d", buf, exp);
}
if (buf != buffer) caml_stat_free(buf);
return res;
}
static int caml_float_of_hex(const char * s, const char * end, double * res)
{
int64_t m = 0; /* the mantissa - top 60 bits at most */
int n_bits = 0; /* total number of bits read */
int m_bits = 0; /* number of bits in mantissa */
int x_bits = 0; /* number of bits after mantissa */
int dec_point = -1; /* bit count corresponding to decimal point */
/* -1 if no decimal point seen */
int exp = 0; /* exponent */
char * p; /* for converting the exponent */
double f;
while (s < end) {
char c = *s++;
switch (c) {
case '.':
if (dec_point >= 0) return -1; /* multiple decimal points */
dec_point = n_bits;
break;
case 'p': case 'P': {
long e;
if (*s == 0) return -1; /* nothing after exponent mark */
e = strtol(s, &p, 10);
if (p != end) return -1; /* ill-formed exponent */
/* Handle exponents larger than int by returning 0/infinity directly.
Mind that INT_MIN/INT_MAX are included in the test so as to capture
the overflow case of strtol on Win64 -- long and int have the same
size there. */
if (e <= INT_MIN) {
*res = 0.;
return 0;
}
else if (e >= INT_MAX) {
*res = m == 0 ? 0. : HUGE_VAL;
return 0;
}
/* regular exponent value */
exp = e;
s = p; /* stop at next loop iteration */
break;
}
default: { /* Nonzero digit */
int d;
if (c >= '0' && c <= '9') d = c - '0';
else if (c >= 'A' && c <= 'F') d = c - 'A' + 10;
else if (c >= 'a' && c <= 'f') d = c - 'a' + 10;
else return -1; /* bad digit */
n_bits += 4;
if (d == 0 && m == 0) break; /* leading zeros are skipped */
if (m_bits < 60) {
/* There is still room in m. Add this digit to the mantissa. */
m = (m << 4) + d;
m_bits += 4;
} else {
/* We've already collected 60 significant bits in m.
Now all we care about is whether there is a nonzero bit
after. In this case, round m to odd so that the later
rounding of m to FP produces the correct result. */
if (d != 0) m |= 1; /* round to odd */
x_bits += 4;
}
break;
}
}
}
if (n_bits == 0) return -1;
/* Convert mantissa to FP. We use a signed conversion because we can
(m has 60 bits at most) and because it is faster
on several architectures. */
f = (double) (int64_t) m;
/* Adjust exponent to take decimal point and extra digits into account */
{
int adj = x_bits;
if (dec_point >= 0) adj = adj + (dec_point - n_bits);
/* saturated addition exp + adj */
if (adj > 0 && exp > INT_MAX - adj)
exp = INT_MAX;
else if (adj < 0 && exp < INT_MIN - adj)
exp = INT_MIN;
else
exp = exp + adj;
}
/* Apply exponent if needed */
if (exp != 0) f = ldexp(f, exp);
/* Done! */
*res = f;
return 0;
}
CAMLprim value caml_float_of_string(value vs)
{
char parse_buffer[64];
char * buf, * dst, * end;
const char *src;
mlsize_t len;
int sign;
double d;
/* Remove '_' characters before conversion */
len = caml_string_length(vs);
buf = len < sizeof(parse_buffer) ? parse_buffer : caml_stat_alloc(len + 1);
src = String_val(vs);
dst = buf;
while (len--) {
char c = *src++;
if (c != '_') *dst++ = c;
}
*dst = 0;
if (dst == buf) goto error;
/* Check for hexadecimal FP constant */
src = buf;
sign = 1;
if (*src == '-') { sign = -1; src++; }
else if (*src == '+') { src++; };
if (src[0] == '0' && (src[1] == 'x' || src[1] == 'X')) {
/* Convert using our hexadecimal FP parser */
if (caml_float_of_hex(src + 2, dst, &d) == -1) goto error;
if (sign < 0) d = -d;
} else {
/* Convert using strtod */
#if defined(HAS_STRTOD_L) && defined(HAS_LOCALE)
d = strtod_l((const char *) buf, &end, caml_locale);
#else
USE_LOCALE;
d = strtod((const char *) buf, &end);
RESTORE_LOCALE;
#endif /* HAS_STRTOD_L */
if (end != dst) goto error;
}
if (buf != parse_buffer) caml_stat_free(buf);
return caml_copy_double(d);
error:
if (buf != parse_buffer) caml_stat_free(buf);
caml_failwith("float_of_string");
return Val_unit; /* not reached */
}
CAMLprim value caml_int_of_float(value f)
{
return Val_long((intnat) Double_val(f));
}
CAMLprim value caml_float_of_int(value n)
{
return caml_copy_double((double) Long_val(n));
}
CAMLprim value caml_neg_float(value f)
{
return caml_copy_double(- Double_val(f));
}
CAMLprim value caml_abs_float(value f)
{
return caml_copy_double(fabs(Double_val(f)));
}
CAMLprim value caml_add_float(value f, value g)
{
return caml_copy_double(Double_val(f) + Double_val(g));
}
CAMLprim value caml_sub_float(value f, value g)
{
return caml_copy_double(Double_val(f) - Double_val(g));
}
CAMLprim value caml_mul_float(value f, value g)
{
return caml_copy_double(Double_val(f) * Double_val(g));
}
CAMLprim value caml_div_float(value f, value g)
{
return caml_copy_double(Double_val(f) / Double_val(g));
}
CAMLprim value caml_exp_float(value f)
{
return caml_copy_double(exp(Double_val(f)));
}
CAMLexport double caml_trunc(double x)
{
#ifdef HAS_C99_FLOAT_OPS
return trunc(x);
#else
return (x >= 0.0)? floor(x) : ceil(x);
#endif
}
CAMLprim value caml_trunc_float(value f)
{
return caml_copy_double(caml_trunc(Double_val(f)));
}
CAMLexport double caml_round(double f)
{
#ifdef HAS_C99_FLOAT_OPS
return round(f);
#else
union { uint64_t i; double d; } u, pred_one_half; /* predecessor of 0.5 */
int e; /* exponent */
u.d = f;
e = (u.i >> 52) & 0x7ff; /* - 0x3ff for the actual exponent */
pred_one_half.i = 0x3FDFFFFFFFFFFFFF; /* 0x1.FFFFFFFFFFFFFp-2 */
if (isfinite(f) && f != 0.) {
if (e >= 52 + 0x3ff) return f; /* f is an integer already */
if (f > 0.0)
/* If we added 0.5 instead of its predecessor, then the
predecessor of 0.5 would be rounded to 1. instead of 0. */
return floor(f + pred_one_half.d);
else
return ceil(f - pred_one_half.d);
}
else
return f;
#endif
}
CAMLprim value caml_round_float(value f)
{
return caml_copy_double(caml_round(Double_val(f)));
}
CAMLprim value caml_floor_float(value f)
{
return caml_copy_double(floor(Double_val(f)));
}
CAMLexport double caml_nextafter(double x, double y)
{
return nextafter(x, y);
}
CAMLprim value caml_nextafter_float(value x, value y)
{
return caml_copy_double(caml_nextafter(Double_val(x), Double_val(y)));
}
#ifndef HAS_WORKING_FMA
union double_as_int64 { double d; uint64_t i; };
#define IEEE754_DOUBLE_BIAS 0x3ff
#define IEEE_EXPONENT(N) (((N) >> 52) & 0x7ff)
#define IEEE_NEGATIVE(N) ((N) >> 63)
//C99 hexa float literals cannot be used, use pow() instead.
#define FL53 (pow(2,53)) //0x1p53
#define FLM53 (pow(2,-53)) //0x1p-53
#define FL54 (pow(2,54)) //0x1p54
#define FLM54 (pow(2,-54)) //0x1p-54
#define FL108 (pow(2,108)) //0x1p108
#define FLM108 (pow(2,-108)) //0x1p-108
#define FLM1074 (pow(2,-1074)) //0x1p-1074
#endif
CAMLexport double caml_fma(double x, double y, double z)
{
#ifdef HAS_WORKING_FMA
return fma(x, y, z);
#else // Emulation of FMA, from S. Boldo and G. Melquiond, "Emulation
// of a FMA and Correctly Rounded Sums: Proved Algorithms Using
// Rounding to Odd," in IEEE Transactions on Computers, vol. 57,
// no. 4, pp. 462-471, April 2008. Special cases implementation
// comes from glibc's IEEE754 FMA emulation.
// Only valid for double precision and round-to-nearest mode.
union double_as_int64 u, v, w;
union double_as_int64 ora;
double mh, ml, xh, xl, yh, yl, t;
double ah, al;
double orah, oral;
double t1, t2;
double tiny;
int neg, adjust = 0;
u.d = x;
v.d = y;
w.d = z;
if ( IEEE_EXPONENT(u.i) + IEEE_EXPONENT(v.i) >= 0x7FF +
IEEE754_DOUBLE_BIAS - DBL_MANT_DIG
|| IEEE_EXPONENT(u.i) >= 0x7ff - DBL_MANT_DIG
|| IEEE_EXPONENT(v.i) >= 0x7ff - DBL_MANT_DIG
|| IEEE_EXPONENT(w.i) >= 0x7ff - DBL_MANT_DIG
|| IEEE_EXPONENT(u.i) + IEEE_EXPONENT(v.i) <=
IEEE754_DOUBLE_BIAS + DBL_MANT_DIG )
{
/* If z is Inf, but x and y are finite, the result should be z
* rather than NaN. */
if (IEEE_EXPONENT(w.i) == 0x7ff &&
IEEE_EXPONENT(u.i) != 0x7ff &&
IEEE_EXPONENT(v.i) != 0x7ff)
return (z + x) + y;
/* If z is zero and x and y are nonzero, compute the result as
x * y to avoid the wrong sign of a zero result if x * y
underflows to 0. */
if (z == 0 && x != 0 && y != 0)
return x * y;
/* If x or y or z is Inf/NaN, or if x * y is zero, compute as
x * y + z. */
if (IEEE_EXPONENT(u.i) == 0x7ff
|| IEEE_EXPONENT(v.i) == 0x7ff
|| IEEE_EXPONENT(w.i) == 0x7ff
|| x == 0
|| y == 0)
return x * y + z;
/* If fma will certainly overflow, compute as x * y. */
if ((IEEE_EXPONENT(u.i) + IEEE_EXPONENT(v.i))
> 0x7ff + IEEE754_DOUBLE_BIAS)
return x * y;
/* If x * y is less than 1/4 of DBL_TRUE_MIN, neither the result
nor whether there is underflow depends on its exact value,
only on its sign. */
if (IEEE_EXPONENT(u.i) + IEEE_EXPONENT(v.i)
< IEEE754_DOUBLE_BIAS - DBL_MANT_DIG - 2)
{
neg = IEEE_NEGATIVE(u.i) ^ IEEE_NEGATIVE(v.i) ;
tiny = neg ? -FLM1074 : FLM1074;
if (IEEE_EXPONENT(w.i) >= 3)
return tiny + z;
/* Scaling up, adding TINY and scaling down produces the
correct result, because in round-to-nearest mode adding
TINY has no effect and in other modes double rounding is
harmless. But it may not produce required underflow
exceptions. */
v.d = z * FL54 + tiny;
return v.d * FLM54;
}
if (IEEE_EXPONENT(u.i) + IEEE_EXPONENT(v.i)
>= 0x7ff + IEEE754_DOUBLE_BIAS - DBL_MANT_DIG)
{
/* Compute 1p-53 times smaller result and multiply at the
end. */
if (IEEE_EXPONENT(u.i) > IEEE_EXPONENT(v.i))
x *= FLM53;
else
y *= FLM53;
/* If x + y exponent is very large and z exponent is very small,
it doesn't matter if we don't adjust it. */
if (IEEE_EXPONENT(w.i) > DBL_MANT_DIG)
z *= FLM53;
adjust = 1;
}
else if (IEEE_EXPONENT(w.i) >= 0x7ff - DBL_MANT_DIG)
{
/* Similarly. If z exponent is very large and x and y
exponents are very small, adjust them up to avoid
spurious underflows, rather than down. */
if (IEEE_EXPONENT(u.i) + IEEE_EXPONENT(v.i)
<= IEEE754_DOUBLE_BIAS + 2 * DBL_MANT_DIG)
{
if (IEEE_EXPONENT(u.i) > IEEE_EXPONENT(v.i))
x *= FL108;
else
y *= FL108;
}
else if (IEEE_EXPONENT(u.i) > IEEE_EXPONENT(v.i))
{
if (IEEE_EXPONENT(u.i) > DBL_MANT_DIG)
x *= FLM53;
}
else if (IEEE_EXPONENT(v.i) > DBL_MANT_DIG)
y *= FLM53;
z *= FLM53;
adjust = 1;
}
else if (IEEE_EXPONENT(u.i) >= 0x7ff - DBL_MANT_DIG)
{
x *= FLM53;
y *= FL53;
}
else if (IEEE_EXPONENT(v.i) >= 0x7ff - DBL_MANT_DIG)
{
y *= FLM53;
x *= FL53;
}
else /* if (IEEE_EXPONENT(u.i) + IEEE_EXPONENT(v.i) <=
IEEE754_DOUBLE_BIAS + DBL_MANT_DIG) */
{
if (IEEE_EXPONENT(u.i) > IEEE_EXPONENT(v.i))
x *= FL108;
else
y *= FL108;
if (IEEE_EXPONENT(w.i) <= 4 * DBL_MANT_DIG + 6)
{
z *= FL108;
adjust = -1;
}
}
}
/* Ensure correct sign of exact 0 + 0. */
if ((x == 0 || y == 0) && z == 0)
return x * y + z;
// Error-free multiplication: mh + ml = x * y
mh = x * y;
t = x * 134217729.0;
xh = t - (t - x);
xl = x - xh;
t = y * 134217729.0;
yh = t - (t - y);
yl = y - yh;
ml = xl * yl - (((mh - xh * yh) - xl * yh) - xh * yl);
// Error-free addition: ah + al = z + mh
ah = z + mh;
t = ah - z;
al = (z - (ah - t)) + (mh - t);
/* If the result is an exact zero, ensure it has the correct sign. */
if (ah == 0 && ml == 0)
return z + mh;
// Normalize ah, al, ml.
t1 = al + ml;
t = t1 - al;
t2 = (al - (t1 - t)) + (ml - t);
al = t1;
ml = t2;
t1 = ah + al;
t = t1 - ah;
t2 = (ah - (t1 - t)) + (al - t);
ah = t1;
al = t2;
// Odd-rounded addition: ora = al + ml.
orah = al + ml;
oral = (al - orah) + ml;
if ( oral != 0.0 )
{
ora.d = orah;
if ( !(ora.i & 1) )
{
if ( (oral > 0.0) ^ (orah < 0.0) )
ora.i++;
else
ora.i--;
orah = ora.d;
}
}
// Rounded addition: ra = ah + orah.
if ( adjust > 0 )
return (ah + orah) * FL53;
else if ( adjust < 0 )
return (ah + orah) * FLM108;
else
return ah + orah;
#endif
}
CAMLprim value caml_fma_float(value f1, value f2, value f3)
{
return caml_copy_double(caml_fma(Double_val(f1),
Double_val(f2), Double_val(f3)));
}
CAMLprim value caml_fmod_float(value f1, value f2)
{
return caml_copy_double(fmod(Double_val(f1), Double_val(f2)));
}
CAMLprim value caml_frexp_float(value f)
{
CAMLparam1 (f);
CAMLlocal2 (res, mantissa);
int exponent;
mantissa = caml_copy_double(frexp (Double_val(f), &exponent));
res = caml_alloc_tuple(2);
Field(res, 0) = mantissa;
Field(res, 1) = Val_int(exponent);
CAMLreturn (res);
}
// Seems dumb but intnat could not correspond to int type.
double caml_ldexp_float_unboxed(double f, intnat i)
{
return ldexp(f, (int) i);
}
CAMLprim value caml_ldexp_float(value f, value i)
{
return caml_copy_double(ldexp(Double_val(f), Int_val(i)));
}
CAMLprim value caml_log_float(value f)
{
return caml_copy_double(log(Double_val(f)));
}
CAMLprim value caml_log10_float(value f)
{
return caml_copy_double(log10(Double_val(f)));
}
CAMLprim value caml_modf_float(value f)
{
double frem;
CAMLparam1 (f);
CAMLlocal3 (res, quo, rem);
quo = caml_copy_double(modf (Double_val(f), &frem));
rem = caml_copy_double(frem);
res = caml_alloc_tuple(2);
Field(res, 0) = quo;
Field(res, 1) = rem;
CAMLreturn (res);
}
CAMLprim value caml_sqrt_float(value f)
{
return caml_copy_double(sqrt(Double_val(f)));
}
CAMLprim value caml_power_float(value f, value g)
{
return caml_copy_double(pow(Double_val(f), Double_val(g)));
}
CAMLprim value caml_sin_float(value f)
{
return caml_copy_double(sin(Double_val(f)));
}
CAMLprim value caml_sinh_float(value f)
{
return caml_copy_double(sinh(Double_val(f)));
}
CAMLprim value caml_cos_float(value f)
{
return caml_copy_double(cos(Double_val(f)));
}
CAMLprim value caml_cosh_float(value f)
{
return caml_copy_double(cosh(Double_val(f)));
}
CAMLprim value caml_tan_float(value f)
{
return caml_copy_double(tan(Double_val(f)));
}
CAMLprim value caml_tanh_float(value f)
{
return caml_copy_double(tanh(Double_val(f)));
}
CAMLprim value caml_asin_float(value f)
{
return caml_copy_double(asin(Double_val(f)));
}
CAMLprim value caml_acos_float(value f)
{
return caml_copy_double(acos(Double_val(f)));
}
CAMLprim value caml_atan_float(value f)
{
return caml_copy_double(atan(Double_val(f)));
}
CAMLprim value caml_atan2_float(value f, value g)
{
return caml_copy_double(atan2(Double_val(f), Double_val(g)));
}
CAMLprim value caml_ceil_float(value f)
{
return caml_copy_double(ceil(Double_val(f)));
}
CAMLexport double caml_hypot(double x, double y)
{
#ifdef HAS_C99_FLOAT_OPS
return hypot(x, y);
#else
double tmp, ratio;
x = fabs(x); y = fabs(y);
if (x != x) /* x is NaN */
return y > DBL_MAX ? y : x; /* PR#6321 */
if (y != y) /* y is NaN */
return x > DBL_MAX ? x : y; /* PR#6321 */
if (x < y) { tmp = x; x = y; y = tmp; }
if (x == 0.0) return 0.0;
ratio = y / x;
return x * sqrt(1.0 + ratio * ratio);
#endif
}
CAMLprim value caml_hypot_float(value f, value g)
{
return caml_copy_double(caml_hypot(Double_val(f), Double_val(g)));
}
/* These emulations of expm1() and log1p() are due to William Kahan.
See http://www.plunk.org/~hatch/rightway.php */
CAMLexport double caml_expm1(double x)
{
#ifdef HAS_C99_FLOAT_OPS
return expm1(x);
#else
double u = exp(x);
if (u == 1.)
return x;
if (u - 1. == -1.)
return -1.;
return (u - 1.) * x / log(u);
#endif
}
CAMLexport double caml_log1p(double x)
{
#ifdef HAS_C99_FLOAT_OPS
return log1p(x);
#else
double u = 1. + x;
if (u == 1.)
return x;
else
return log(u) * x / (u - 1.);
#endif
}
CAMLprim value caml_expm1_float(value f)
{
return caml_copy_double(caml_expm1(Double_val(f)));
}
CAMLprim value caml_log1p_float(value f)
{
return caml_copy_double(caml_log1p(Double_val(f)));
}
union double_as_two_int32 {
double d;
#if defined(ARCH_BIG_ENDIAN) || (defined(__arm__) && !defined(__ARM_EABI__))
struct { uint32_t h; uint32_t l; } i;
#else
struct { uint32_t l; uint32_t h; } i;
#endif
};
CAMLexport double caml_copysign(double x, double y)
{
#ifdef HAS_C99_FLOAT_OPS
return copysign(x, y);
#else
union double_as_two_int32 ux, uy;
ux.d = x;
uy.d = y;
ux.i.h &= 0x7FFFFFFFU;
ux.i.h |= (uy.i.h & 0x80000000U);
return ux.d;
#endif
}
CAMLprim value caml_copysign_float(value f, value g)
{
return caml_copy_double(caml_copysign(Double_val(f), Double_val(g)));
}
CAMLprim value caml_signbit(double x)
{
#ifdef HAS_C99_FLOAT_OPS
return Val_bool(signbit(x));
#else
union double_as_two_int32 ux;
ux.d = x;
return Val_bool(ux.i.h >> 31);
#endif
}
CAMLprim value caml_signbit_float(value f)
{
return caml_signbit(Double_val(f));
}
CAMLprim value caml_neq_float(value f, value g)
{
return Val_bool(Double_val(f) != Double_val(g));
}
#define DEFINE_NAN_CMP(op) (value f, value g) \
{ \
return Val_bool(Double_val(f) op Double_val(g)); \
}
intnat caml_float_compare_unboxed(double f, double g)
{
/* If one or both of f and g is NaN, order according to the convention
NaN = NaN and NaN < x for all other floats x. */
/* This branchless implementation is from GPR#164.
Note that [f == f] if and only if f is not NaN.
We expand each subresult of the expression to
avoid sign-extension on 64bit. GPR#2250.
See also translation of Pcompare_floats in asmcomp/cmmgen.ml */
intnat res =
(intnat)(f > g) - (intnat)(f < g) + (intnat)(f == f) - (intnat)(g == g);
return res;
}
CAMLprim value caml_eq_float DEFINE_NAN_CMP(==)
CAMLprim value caml_le_float DEFINE_NAN_CMP(<=)
CAMLprim value caml_lt_float DEFINE_NAN_CMP(<)
CAMLprim value caml_ge_float DEFINE_NAN_CMP(>=)
CAMLprim value caml_gt_float DEFINE_NAN_CMP(>)
CAMLprim value caml_float_compare(value vf, value vg)
{
return Val_int(caml_float_compare_unboxed(Double_val(vf),Double_val(vg)));
}
enum { FP_normal, FP_subnormal, FP_zero, FP_infinite, FP_nan };
value caml_classify_float_unboxed(double vd)
{
#ifdef ARCH_SIXTYFOUR
union { double d; uint64_t i; } u;
uint64_t n;
uint32_t e;
u.d = vd;
n = u.i << 1; /* shift sign bit off */
if (n == 0) return Val_int(FP_zero);
e = n >> 53; /* extract exponent */
if (e == 0) return Val_int(FP_subnormal);
if (e == 0x7FF) {
if (n << 11 == 0) /* shift exponent off */
return Val_int(FP_infinite);
else
return Val_int(FP_nan);
}
return Val_int(FP_normal);
#else
union double_as_two_int32 u;
uint32_t h, l;
u.d = vd;
h = u.i.h; l = u.i.l;
l = l | (h & 0xFFFFF);
h = h & 0x7FF00000;
if ((h | l) == 0)
return Val_int(FP_zero);
if (h == 0)
return Val_int(FP_subnormal);
if (h == 0x7FF00000) {
if (l == 0)
return Val_int(FP_infinite);
else
return Val_int(FP_nan);
}
return Val_int(FP_normal);
#endif
}
CAMLprim value caml_classify_float(value vd)
{
return caml_classify_float_unboxed(Double_val(vd));
}