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-rw-r--r--modules/fdlibm/src/s_truncf.cpp52
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diff --git a/modules/fdlibm/src/s_truncf.cpp b/modules/fdlibm/src/s_truncf.cpp
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+++ b/modules/fdlibm/src/s_truncf.cpp
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+/* @(#)s_floor.c 5.1 93/09/24 */
+/*
+ * ====================================================
+ * 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 <sys/cdefs.h>
+//__FBSDID("$FreeBSD$");
+
+/*
+ * truncf(x)
+ * Return x rounded toward 0 to integral value
+ * Method:
+ * Bit twiddling.
+ * Exception:
+ * Inexact flag raised if x not equal to truncf(x).
+ */
+
+#include "math_private.h"
+
+static const float huge = 1.0e30F;
+
+float
+truncf(float x)
+{
+ int32_t i0,j0;
+ u_int32_t i;
+ GET_FLOAT_WORD(i0,x);
+ j0 = ((i0>>23)&0xff)-0x7f;
+ if(j0<23) {
+ if(j0<0) { /* raise inexact if x != 0 */
+ if(huge+x>0.0F) /* |x|<1, so return 0*sign(x) */
+ i0 &= 0x80000000;
+ } else {
+ i = (0x007fffff)>>j0;
+ if((i0&i)==0) return x; /* x is integral */
+ if(huge+x>0.0F) /* raise inexact flag */
+ i0 &= (~i);
+ }
+ } else {
+ if(j0==0x80) return x+x; /* inf or NaN */
+ else return x; /* x is integral */
+ }
+ SET_FLOAT_WORD(x,i0);
+ return x;
+}