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/************************************************************************
* *
* The SB-Prolog System *
* Copyright SUNY at Stony Brook, 1986; University of Arizona, 1987 *
* *
************************************************************************/
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/* arith.c */
/* some builtins for arithmetic functions */
#include "builtin.h"
extern double floatval();
extern LONG makefloat();
b_FLOATC() /* F, M, E, S */
{
/* reg1 (F) is either a variable or a number (in WAM format);
* reg2 (M) is either a number (in WAM format) or a variable;
* reg3 (E) is either an integer or a variable. The intended
* interpretation is that M and E represent the mantissa and exponent,
* respectively, of the floating point number F. Either F, or
* both M and E, are assumed to be bound (the selector reg4 (S)
* tells us which case it is). No checking for this is done here.
*/
register LONG op1, op2, op3, op4;
register LONG_PTR top;
double fval;
int exp0;
op1 = reg[1]; DEREF(op1);
op2 = reg[2]; DEREF(op2);
op3 = reg[3]; DEREF(op3);
op4 = reg[4]; DEREF(op4);
switch (INTVAL(op4)) {
case 0: fval = frexp(NUMVAL(op1), &exp0);
FOLLOW(op2) = makefloat(fval);
PUSHTRAIL(op2);
FOLLOW(op3) = MAKEINT(exp0);
PUSHTRAIL(op3);
break;
case 1: fval = ldexp((double)NUMVAL(op2), (int)INTVAL(op3));
FOLLOW(op1) = makefloat(fval);
PUSHTRAIL(op1);
break;
case 3: fval = ldexp((double)NUMVAL(op2), (int)INTVAL(op3));
if (floatval(op1) != fval) {FAIL0;}
break;
}
}
b_ARITH()
{
register LONG op1, op2, op3;
register LONG_PTR top;
double y;
op1 = reg[1];
op2 = reg[2];
op3 = reg[3]; DEREF(op3);
switch (INTVAL(op3)) {
case 0: DEREF(op2);
if (!unify(op1, makefloat(log((double)NUMVAL(op2)))))
{FAIL0;}
break;
case 1: DEREF(op1);
if (!unify(makefloat(exp((double)NUMVAL(op1))), op2))
{FAIL0;}
break;
case 2: DEREF(op2);
if (!unify(op1, makefloat(sqrt((double)NUMVAL(op2)))))
{FAIL0;}
break;
case 3: DEREF(op1);
y = (double)NUMVAL(op1);
if (!unify(makefloat(y * y), op2))
{FAIL0;}
break;
case 4: DEREF(op1);
if (!unify(makefloat(sin((double)NUMVAL(op1))), op2))
{FAIL0;}
break;
case 5: DEREF(op2);
if (!unify(op1, makefloat(asin((double)NUMVAL(op2)))))
{FAIL0;}
break;
}
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.