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-rw-r--r--newlib/libm/common/sf_round.c78
1 files changed, 78 insertions, 0 deletions
diff --git a/newlib/libm/common/sf_round.c b/newlib/libm/common/sf_round.c
new file mode 100644
index 0000000..75a72fe
--- /dev/null
+++ b/newlib/libm/common/sf_round.c
@@ -0,0 +1,78 @@
+/*
+ * ====================================================
+ * 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 "fdlibm.h"
+
+#ifdef __STDC__
+ float roundf(float x)
+#else
+ float roundf(x)
+ float x;
+#endif
+{
+ int signbit;
+ int w;
+ /* Most significant word, least significant word. */
+ int exponent_less_127;
+
+ GET_FLOAT_WORD(w, x);
+
+ /* Extract sign bit. */
+ signbit = w & 0x80000000;
+
+ /* Extract exponent field. */
+ exponent_less_127 = ((w & 0x7f800000) >> 23) - 127;
+
+ if (exponent_less_127 < 23)
+ {
+ if (exponent_less_127 < 0)
+ {
+ w &= 0x80000000;
+ if (exponent_less_127 == -1)
+ /* Result is +1.0 or -1.0. */
+ w |= (127 << 23);
+ }
+ else
+ {
+ unsigned int exponent_mask = 0x007fffff >> exponent_less_127;
+ if ((w & exponent_mask) == 0)
+ /* x has an integral value. */
+ return x;
+
+ w += 0x00400000 >> exponent_less_127;
+ w &= ~exponent_mask;
+ }
+ }
+ else
+ {
+ if (exponent_less_127 == 128)
+ /* x is NaN or infinite. */
+ return x + x;
+ else
+ return x;
+ }
+ SET_FLOAT_WORD(x, w);
+ return x;
+}
+
+#ifdef _DOUBLE_IS_32BITS
+
+#ifdef __STDC__
+ double round(double x)
+#else
+ double round(x)
+ double x;
+#endif
+{
+ return (double) roundf((float) x);
+}
+
+#endif /* defined(_DOUBLE_IS_32BITS) */