ceilf.c File Reference

#include "libm.h"
#include "libm_util.h"
#include "libm_errno.h"
#include "libm_inlines.h"

Include dependency graph for ceilf.c:

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Macros
#define	USE_HANDLE_ERRORF

Functions
float FN_PROTOTYPE()	ceilf (float x)

Macro Definition Documentation

USE_HANDLE_ERRORF

#define USE_HANDLE_ERRORF

Definition at line 31 of file ceilf.c.

Function Documentation

ceilf()

float FN_PROTOTYPE() ceilf

(

float

x

)

Definition at line 40 of file ceilf.c.

{
  float r;
  int rexp, xneg;
  unsigned int ux, ax, ur, mask;
 
  GET_BITS_SP32(x, ux);
  ax = ux & (~SIGNBIT_SP32);
  xneg = (ux != ax);
 
  if (ax >= 0x4b800000)
    {
      /* abs(x) is either NaN, infinity, or >= 2^24 */
      if (ax > 0x7f800000)
        /* x is NaN */
        return _handle_errorf("ceilf", OP_CEIL, ux, _DOMAIN, 0, EDOM, x, 
            0.0F, 1);
      else
        return x;
    }
  else if (ax < 0x3f800000) /* abs(x) < 1.0 */
    {
      if (ax == 0x00000000)
        /* x is +zero or -zero; return the same zero */
        return x;
      else if (xneg) /* x < 0.0 */
      {
        PUT_BITS_SP32(SIGNBIT_SP32, r);  /* return -0.0 */
        return r;
      }
      else
        return 1.0F;
    }
  else
    {
      rexp = ((ux & EXPBITS_SP32) >> EXPSHIFTBITS_SP32) - EXPBIAS_SP32;
      /* Mask out the bits of r that we don't want */
      mask = (1 << (EXPSHIFTBITS_SP32 - rexp)) - 1;
      ur = (ux & ~mask);
      PUT_BITS_SP32(ur, r);
 
      if (xneg || (ux == ur)) return r;
      else
        /* We threw some bits away and x was positive */
        return r + 1.0F;
    }
}