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-rw-r--r--REORG.TODO/sysdeps/ieee754/dbl-64/s_modf.c86
1 files changed, 86 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/ieee754/dbl-64/s_modf.c b/REORG.TODO/sysdeps/ieee754/dbl-64/s_modf.c
new file mode 100644
index 0000000000..0a1e13008f
--- /dev/null
+++ b/REORG.TODO/sysdeps/ieee754/dbl-64/s_modf.c
@@ -0,0 +1,86 @@
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/*
+ * modf(double x, double *iptr)
+ * return fraction part of x, and return x's integral part in *iptr.
+ * Method:
+ * Bit twiddling.
+ *
+ * Exception:
+ * No exception.
+ */
+
+#include <math.h>
+#include <math_private.h>
+
+static const double one = 1.0;
+
+double
+__modf (double x, double *iptr)
+{
+ int32_t i0, i1, j0;
+ u_int32_t i;
+ EXTRACT_WORDS (i0, i1, x);
+ j0 = ((i0 >> 20) & 0x7ff) - 0x3ff; /* exponent of x */
+ if (j0 < 20) /* integer part in high x */
+ {
+ if (j0 < 0) /* |x|<1 */
+ {
+ INSERT_WORDS (*iptr, i0 & 0x80000000, 0); /* *iptr = +-0 */
+ return x;
+ }
+ else
+ {
+ i = (0x000fffff) >> j0;
+ if (((i0 & i) | i1) == 0) /* x is integral */
+ {
+ *iptr = x;
+ INSERT_WORDS (x, i0 & 0x80000000, 0); /* return +-0 */
+ return x;
+ }
+ else
+ {
+ INSERT_WORDS (*iptr, i0 & (~i), 0);
+ return x - *iptr;
+ }
+ }
+ }
+ else if (__glibc_unlikely (j0 > 51)) /* no fraction part */
+ {
+ *iptr = x * one;
+ /* We must handle NaNs separately. */
+ if (j0 == 0x400 && ((i0 & 0xfffff) | i1))
+ return x * one;
+ INSERT_WORDS (x, i0 & 0x80000000, 0); /* return +-0 */
+ return x;
+ }
+ else /* fraction part in low x */
+ {
+ i = ((u_int32_t) (0xffffffff)) >> (j0 - 20);
+ if ((i1 & i) == 0) /* x is integral */
+ {
+ *iptr = x;
+ INSERT_WORDS (x, i0 & 0x80000000, 0); /* return +-0 */
+ return x;
+ }
+ else
+ {
+ INSERT_WORDS (*iptr, i0, i1 & (~i));
+ return x - *iptr;
+ }
+ }
+}
+weak_alias (__modf, modf)
+#ifdef NO_LONG_DOUBLE
+strong_alias (__modf, __modfl)
+weak_alias (__modf, modfl)
+#endif