You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
79 lines
2.0 KiB
79 lines
2.0 KiB
/***
|
|
*ceil.c - ceiling
|
|
*
|
|
* Copyright (c) 1991-2001, Microsoft Corporation. All rights reserved.
|
|
*
|
|
*Purpose:
|
|
*
|
|
*Revision History:
|
|
* 8-24-91 GDP written
|
|
* 1-09-92 GDP support IEEE exceptions
|
|
* 6-23-92 GDP ceil(INF) now returns INF (NCEG spec)
|
|
* 02-06-95 JWM Mac merge
|
|
* 01-26-01 PML Pentium4 merge
|
|
*
|
|
*******************************************************************************/
|
|
#include <math.h>
|
|
#include <trans.h>
|
|
|
|
extern double _frnd(double);
|
|
|
|
|
|
/***
|
|
*double ceil(double x) - ceiling
|
|
*
|
|
*Purpose:
|
|
* Return a double representing the smallest integer that is
|
|
* greater than or equal to x
|
|
*
|
|
*Entry:
|
|
*
|
|
*Exit:
|
|
*
|
|
*Exceptions:
|
|
* P, I
|
|
*******************************************************************************/
|
|
static uintptr_t newcw = (ICW & ~IMCW_RC) | (IRC_UP & IMCW_RC);
|
|
|
|
|
|
|
|
#if !defined(_M_IX86)
|
|
double ceil(double x)
|
|
#else
|
|
double _ceil_default(double x)
|
|
#endif
|
|
{
|
|
uintptr_t savedcw;
|
|
double result;
|
|
|
|
/* save user fp control word */
|
|
savedcw = _ctrlfp(newcw,IMCW); /* round up */
|
|
|
|
/* check for infinity or NAN */
|
|
if (IS_D_SPECIAL(x)){
|
|
switch (_sptype(x)) {
|
|
case T_PINF:
|
|
case T_NINF:
|
|
RETURN(savedcw,x);
|
|
case T_QNAN:
|
|
return _handle_qnan1(OP_CEIL, x, savedcw);
|
|
default: //T_SNAN
|
|
return _except1(FP_I, OP_CEIL, x, _s2qnan(x), savedcw);
|
|
}
|
|
}
|
|
|
|
result = _frnd(x); /* round according to the current rounding mode */
|
|
|
|
// In general, the Precision Exception should be raised if
|
|
// _frnd reports a precision loss. In order to detect this with
|
|
// masked exceptions, the status word needs to be cleared.
|
|
// However, we want to avoid this, since the 387 instruction
|
|
// set does not provide an fast way to restore the status word
|
|
|
|
if (result == x) {
|
|
RETURN(savedcw,result);
|
|
}
|
|
else {
|
|
RETURN_INEXACT1(OP_CEIL, x, result, savedcw);
|
|
}
|
|
}
|