remove LFS64 symbol aliases; replace with dynamic linker remapping

[musl] / src / math / roundf.c

diff --git a/src/math/roundf.c b/src/math/roundf.c
index 662a454..e8210af 100644 (file)
--- a/src/math/roundf.c
+++ b/src/math/roundf.c
@@ -1,48 +1,36 @@
-/* origin: FreeBSD /usr/src/lib/msun/src/s_roundf.c */
-/*-
- * Copyright (c) 2003, Steven G. Kargl
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice unmodified, this list of conditions, and the following
- *    disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
- * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
- * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
+#include "libm.h"
 
-#include <math.h>
+#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 roundf(float x)
 {
-       float t;
+       union {float f; uint32_t i;} u = {x};
+       int e = u.i >> 23 & 0xff;
+       float_t y;
 
-       if (!isfinite(x))
+       if (e >= 0x7f+23)
                return x;
-
-       if (x >= 0.0) {
-               t = floorf(x);
-               if (t - x <= -0.5)
-                       t += 1.0;
-               return t;
-       } else {
-               t = floorf(-x);
-               if (t + x <= -0.5)
-                       t += 1.0;
-               return -t;
+       if (u.i >> 31)
+               x = -x;
+       if (e < 0x7f-1) {
+               FORCE_EVAL(x + toint);
+               return 0*u.f;
        }
+       y = x + toint - toint - x;
+       if (y > 0.5f)
+               y = y + x - 1;
+       else if (y <= -0.5f)
+               y = y + x + 1;
+       else
+               y = y + x;
+       if (u.i >> 31)
+               y = -y;
+       return y;
 }