aboutsummaryrefslogtreecommitdiff
path: root/math/s_nexttowardf.c
diff options
context:
space:
mode:
Diffstat (limited to 'math/s_nexttowardf.c')
-rw-r--r--math/s_nexttowardf.c86
1 files changed, 86 insertions, 0 deletions
diff --git a/math/s_nexttowardf.c b/math/s_nexttowardf.c
new file mode 100644
index 0000000..1a10266
--- /dev/null
+++ b/math/s_nexttowardf.c
@@ -0,0 +1,86 @@
+/* Single precision version of nexttoward.c.
+ Conversion to IEEE single float by Jakub Jelinek, jj@ultra.linux.cz. */
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/* IEEE functions
+ * nexttowardf(x,y)
+ * return the next machine floating-point number of x in the
+ * direction toward y.
+ * This is for machines which use the same binary type for double and
+ * long double.
+ * Special cases:
+ */
+
+#include <math.h>
+#include "math_private.h"
+#include <float.h>
+
+#ifdef __STDC__
+ float __nexttowardf(float x, long double y)
+#else
+ float __nexttowardf(x,y)
+ float x;
+ long double y;
+#endif
+{
+ int32_t hx,hy,ix,iy;
+ u_int32_t ly;
+
+ GET_FLOAT_WORD(hx,x);
+ EXTRACT_WORDS(hy,ly,y);
+ ix = hx&0x7fffffff; /* |x| */
+ iy = hy&0x7fffffff; /* |y| */
+
+ if((ix>0x7f800000) || /* x is nan */
+ ((iy>=0x7ff00000)&&((iy-0x7ff00000)|ly)!=0)) /* y is nan */
+ return x+y;
+ if((long double) x==y) return y; /* x=y, return y */
+ if(ix==0) { /* x == 0 */
+ float x2;
+ SET_FLOAT_WORD(x,(u_int32_t)(hy&0x80000000)|1);/* return +-minsub*/
+ x2 = x*x;
+ if(x2==x) return x2; else return x; /* raise underflow flag */
+ }
+ if(hx>=0) { /* x > 0 */
+ if(hy<0||(ix>>23)>(iy>>20)-0x380
+ || ((ix>>23)==(iy>>20)-0x380
+ && (ix&0x7fffff)>(((hy<<3)|(ly>>29))&0x7fffff))) /* x > y, x -= ulp */
+ hx -= 1;
+ else /* x < y, x += ulp */
+ hx += 1;
+ } else { /* x < 0 */
+ if(hy>=0||(ix>>23)>(iy>>20)-0x380
+ || ((ix>>23)==(iy>>20)-0x380
+ && (ix&0x7fffff)>(((hy<<3)|(ly>>29))&0x7fffff))) /* x < y, x -= ulp */
+ hx -= 1;
+ else /* x > y, x += ulp */
+ hx += 1;
+ }
+ hy = hx&0x7f800000;
+ if(hy>=0x7f800000) {
+ x = x+x; /* overflow */
+ if (FLT_EVAL_METHOD != 0)
+ /* Force conversion to float. */
+ asm ("" : "=m"(x) : "m"(x));
+ return x;
+ }
+ if(hy<0x00800000) { /* underflow */
+ float x2 = x*x;
+ if(x2!=x) { /* raise underflow flag */
+ SET_FLOAT_WORD(x2,hx);
+ return x2;
+ }
+ }
+ SET_FLOAT_WORD(x,hx);
+ return x;
+}
+weak_alias (__nexttowardf, nexttowardf)