initial check-in, version 0.5.0 v0.5.0

1 files changed, 58 insertions, 0 deletions

diff --git a/src/math/s_floorf.c b/src/math/s_floorf.c
new file mode 100644
index 00000000..1164decc
--- /dev/null
+++ b/src/math/s_floorf.c
@@ -0,0 +1,58 @@
+/* s_floorf.c -- float version of s_floor.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.
+ * ====================================================
+ */
+
+/*
+ * floorf(x)
+ * Return x rounded toward -inf to integral value
+ * Method:
+ *      Bit twiddling.
+ * Exception:
+ *      Inexact flag raised if x not equal to floorf(x).
+ */
+
+#include <math.h>
+#include "math_private.h"
+
+static const float huge = 1.0e30;
+
+float
+floorf(float x)
+{
+        int32_t i0,j0;
+        uint32_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>(float)0.0) {/* return 0*sign(x) if |x|<1 */
+                    if(i0>=0) {i0=0;}
+                    else if((i0&0x7fffffff)!=0)
+                        { i0=0xbf800000;}
+                }
+            } else {
+                i = (0x007fffff)>>j0;
+                if((i0&i)==0) return x; /* x is integral */
+                if(huge+x>(float)0.0) { /* raise inexact flag */
+                    if(i0<0) i0 += (0x00800000)>>j0;
+                    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;
+}