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-rw-r--r--src/math/modff.c51
1 files changed, 51 insertions, 0 deletions
diff --git a/src/math/modff.c b/src/math/modff.c
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--- /dev/null
+++ b/src/math/modff.c
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+/* origin: FreeBSD /usr/src/lib/msun/src/s_modff.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 "libm.h"
+
+static const float one = 1.0;
+
+float modff(float x, float *iptr)
+{
+	int32_t i0,j0;
+	uint32_t i;
+
+	GET_FLOAT_WORD(i0, x);
+	j0 = ((i0>>23) & 0xff) - 0x7f;  /* exponent of x */
+	if (j0 < 23) {  /* integer part in x */
+		if (j0 < 0) {  /* |x| < 1 */
+			SET_FLOAT_WORD(*iptr, i0 & 0x80000000);  /* *iptr = +-0 */
+			return x;
+		}
+		i = 0x007fffff >> j0;
+		if ((i0&i) == 0) {  /* x is integral */
+			uint32_t ix;
+			*iptr = x;
+			GET_FLOAT_WORD(ix, x);
+			SET_FLOAT_WORD(x, ix & 0x80000000);  /* return +-0 */
+			return x;
+		}
+		SET_FLOAT_WORD(*iptr, i0&~i);
+		return x - *iptr;
+	} else {        /* no fraction part */
+		uint32_t ix;
+		*iptr = x*one;
+		if (x != x)  /* NaN */
+			return x;
+		GET_FLOAT_WORD(ix, x);
+		SET_FLOAT_WORD(x, ix & 0x80000000);  /* return +-0 */
+		return x;
+	}
+}