/* Primitive operations on floating point for GNU Emacs Lisp interpreter.
-Copyright (C) 1988, 1993-1994, 1999, 2001-2013 Free Software Foundation,
+Copyright (C) 1988, 1993-1994, 1999, 2001-2016 Free Software Foundation,
Inc.
-Author: Wolfgang Rupprecht
-(according to ack.texi)
+Author: Wolfgang Rupprecht (according to ack.texi)
This file is part of GNU Emacs.
GNU Emacs is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
-the Free Software Foundation, either version 3 of the License, or
-(at your option) any later version.
+the Free Software Foundation, either version 3 of the License, or (at
+your option) any later version.
GNU Emacs is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
#include <math.h>
-#ifndef isfinite
-# define isfinite(x) ((x) - (x) == 0)
-#endif
-#ifndef isnan
-# define isnan(x) ((x) != (x))
-#endif
+/* 'isfinite' and 'isnan' cause build failures on Solaris 10 with the
+ bundled GCC in c99 mode. Work around the bugs with simple
+ implementations that are good enough. */
+#undef isfinite
+#define isfinite(x) ((x) - (x) == 0)
+#undef isnan
+#define isnan(x) ((x) != (x))
/* Check that X is a floating point number. */
}
DEFUN ("isnan", Fisnan, Sisnan, 1, 1, 0,
- doc: /* Return non nil iff argument X is a NaN. */)
+ doc: /* Return non nil if argument X is a NaN. */)
(Lisp_Object x)
{
CHECK_FLOAT (x);
return Fcons (make_float (sgnfcand), make_number (exponent));
}
-DEFUN ("ldexp", Fldexp, Sldexp, 1, 2, 0,
- doc: /* Construct number X from significand SGNFCAND and exponent EXP.
-Returns the floating point value resulting from multiplying SGNFCAND
-(the significand) by 2 raised to the power of EXP (the exponent). */)
+DEFUN ("ldexp", Fldexp, Sldexp, 2, 2, 0,
+ doc: /* Return SGNFCAND * 2**EXPONENT, as a floating point number.
+EXPONENT must be an integer. */)
(Lisp_Object sgnfcand, Lisp_Object exponent)
{
CHECK_NUMBER (exponent);
- return make_float (ldexp (XFLOATINT (sgnfcand), XINT (exponent)));
+ int e = min (max (INT_MIN, XINT (exponent)), INT_MAX);
+ return make_float (ldexp (XFLOATINT (sgnfcand), e));
}
\f
DEFUN ("exp", Fexp, Sexp, 1, 1, 0,
return arg;
}
-/* With C's /, the result is implementation-defined if either operand
- is negative, so take care with negative operands in the following
- integer functions. */
-
static EMACS_INT
ceiling2 (EMACS_INT i1, EMACS_INT i2)
{
- return (i2 < 0
- ? (i1 < 0 ? ((-1 - i1) / -i2) + 1 : - (i1 / -i2))
- : (i1 <= 0 ? - (-i1 / i2) : ((i1 - 1) / i2) + 1));
+ return i1 / i2 + ((i1 % i2 != 0) & ((i1 < 0) == (i2 < 0)));
}
static EMACS_INT
floor2 (EMACS_INT i1, EMACS_INT i2)
{
- return (i2 < 0
- ? (i1 <= 0 ? -i1 / -i2 : -1 - ((i1 - 1) / -i2))
- : (i1 < 0 ? -1 - ((-1 - i1) / i2) : i1 / i2));
+ return i1 / i2 - ((i1 % i2 != 0) & ((i1 < 0) != (i2 < 0)));
}
static EMACS_INT
truncate2 (EMACS_INT i1, EMACS_INT i2)
{
- return (i2 < 0
- ? (i1 < 0 ? -i1 / -i2 : - (i1 / -i2))
- : (i1 < 0 ? - (-i1 / i2) : i1 / i2));
+ return i1 / i2;
}
static EMACS_INT
static double
emacs_rint (double d)
{
- return floor (d + 0.5);
+ double d1 = d + 0.5;
+ double r = floor (d1);
+ return r - (r == d1 && fmod (r, 2) != 0);
}
#endif
Rounding a value equidistant between two integers may choose the
integer closer to zero, or it may prefer an even integer, depending on
-your machine. For example, \(round 2.5\) can return 3 on some
+your machine. For example, (round 2.5) can return 3 on some
systems, but 2 on others. */)
(Lisp_Object arg, Lisp_Object divisor)
{
\f
DEFUN ("fceiling", Ffceiling, Sfceiling, 1, 1, 0,
doc: /* Return the smallest integer no less than ARG, as a float.
-\(Round toward +inf.\) */)
+\(Round toward +inf.) */)
(Lisp_Object arg)
{
double d = extract_float (arg);
DEFUN ("ffloor", Fffloor, Sffloor, 1, 1, 0,
doc: /* Return the largest integer no greater than ARG, as a float.
-\(Round towards -inf.\) */)
+\(Round towards -inf.) */)
(Lisp_Object arg)
{
double d = extract_float (arg);