-/* origin: FreeBSD /usr/src/lib/msun/src/s_rintf.c */
-/*
- * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
- */
-/*
- * ====================================================
- * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
- *
- * Developed at SunPro, a Sun Microsystems, Inc. business.
- * Permission to use, copy, modify, and distribute this
- * software is freely granted, provided that this notice
- * is preserved.
- * ====================================================
- */
+#include <float.h>
+#include <math.h>
+#include <stdint.h>
-#include "libm.h"
-
-static const float
-TWO23[2] = {
- 8.3886080000e+06, /* 0x4b000000 */
- -8.3886080000e+06, /* 0xcb000000 */
-};
+#if FLT_EVAL_METHOD==0
+#define EPS FLT_EPSILON
+#elif FLT_EVAL_METHOD==1
+#define EPS DBL_EPSILON
+#elif FLT_EVAL_METHOD==2
+#define EPS LDBL_EPSILON
+#endif
+static const float_t toint = 1/EPS;
float rintf(float x)
{
- int32_t i0,j0,sx;
- float w,t;
+ union {float f; uint32_t i;} u = {x};
+ int e = u.i>>23 & 0xff;
+ int s = u.i>>31;
+ float_t y;
- GET_FLOAT_WORD(i0, x);
- sx = (i0>>31) & 1;
- j0 = ((i0>>23)&0xff) - 0x7f;
- if (j0 < 23) {
- if (j0 < 0) {
- if ((i0&0x7fffffff) == 0)
- return x;
- STRICT_ASSIGN(float, w, TWO23[sx] + x);
- t = w - TWO23[sx];
- GET_FLOAT_WORD(i0, t);
- SET_FLOAT_WORD(t, (i0&0x7fffffff)|(sx<<31));
- return t;
- }
- STRICT_ASSIGN(float, w, TWO23[sx] + x);
- return w - TWO23[sx];
- }
- if (j0 == 0x80)
- return x+x; /* inf or NaN */
- return x; /* x is integral */
+ if (e >= 0x7f+23)
+ return x;
+ if (s)
+ y = x - toint + toint;
+ else
+ y = x + toint - toint;
+ if (y == 0)
+ return s ? -0.0f : 0.0f;
+ return y;
}