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-rw-r--r--src/math/rintf.c48
1 files changed, 48 insertions, 0 deletions
diff --git a/src/math/rintf.c b/src/math/rintf.c
new file mode 100644
index 00000000..e8d44969
--- /dev/null
+++ b/src/math/rintf.c
@@ -0,0 +1,48 @@
+/* origin: FreeBSD /usr/src/lib/msun/src/s_rintf.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
+TWO23[2] = {
+ 8.3886080000e+06, /* 0x4b000000 */
+ -8.3886080000e+06, /* 0xcb000000 */
+};
+
+float rintf(float x)
+{
+ int32_t i0,j0,sx;
+ float w,t;
+
+ GET_FLOAT_WORD(i0, x);
+ sx = (i0>>31) & 1;
+ j0 = ((i0>>23)&0xff) - 0x7f;
+ if (j0 < 23) {
+ if (j0 < 0) {
+ if ((i0&0x7fffffff) == 0)
+ return x;
+ STRICT_ASSIGN(float, w, TWO23[sx] + x);
+ t = w - TWO23[sx];
+ GET_FLOAT_WORD(i0, t);
+ SET_FLOAT_WORD(t, (i0&0x7fffffff)|(sx<<31));
+ return t;
+ }
+ STRICT_ASSIGN(float, w, TWO23[sx] + x);
+ return w - TWO23[sx];
+ }
+ if (j0 == 0x80)
+ return x+x; /* inf or NaN */
+ return x; /* x is integral */
+}