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Diffstat (limited to 'sysdeps/i386/fpu/s_nexttowardf.c')
-rw-r--r--sysdeps/i386/fpu/s_nexttowardf.c81
1 files changed, 81 insertions, 0 deletions
diff --git a/sysdeps/i386/fpu/s_nexttowardf.c b/sysdeps/i386/fpu/s_nexttowardf.c
new file mode 100644
index 0000000000..150641f335
--- /dev/null
+++ b/sysdeps/i386/fpu/s_nexttowardf.c
@@ -0,0 +1,81 @@
+/* s_nexttowardf.c -- float version of s_nextafter.c.
+ * Special i387 version.
+ * 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.
+ * ====================================================
+ */
+
+#if defined(LIBM_SCCS) && !defined(lint)
+static char rcsid[] = "$NetBSD: $";
+#endif
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+ float __nexttowardf(float x, long double y)
+#else
+ float __nexttowardf(x,y)
+ float x;
+ long double y;
+#endif
+{
+ int32_t hx,ix,iy;
+ u_int32_t hy,ly,esy;
+
+ GET_FLOAT_WORD(hx,x);
+ GET_LDOUBLE_WORDS(esy,hy,ly,y);
+ ix = hx&0x7fffffff; /* |x| */
+ iy = esy&0x7fff; /* |y| */
+
+ /* Intel's extended format has the normally implicit 1 explicit
+ present. Sigh! */
+ if((ix>0x7f800000) || /* x is nan */
+ (iy>=0x7fff&&(((hy&0x7fffffff)|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,((esy&0x8000)<<16)|1);/* return +-minsub*/
+ x2 = x*x;
+ if(x2==x) return x2; else return x; /* raise underflow flag */
+ }
+ if(hx>=0) { /* x > 0 */
+ if(esy>=0x8000||((ix>>23)&0xff)>iy-0x3f80
+ || (((ix>>23)&0xff)==iy-0x3f80
+ && ((ix&0x7fffff)<<8)>(hy&0x7fffffff))) {/* x > y, x -= ulp */
+ hx -= 1;
+ } else { /* x < y, x += ulp */
+ hx += 1;
+ }
+ } else { /* x < 0 */
+ if(esy<0x8000||((ix>>23)&0xff)>iy-0x3f80
+ || (((ix>>23)&0xff)==iy-0x3f80
+ && ((ix&0x7fffff)<<8)>(hy&0x7fffffff))) {/* x < y, x -= ulp */
+ hx -= 1;
+ } else { /* x > y, x += ulp */
+ hx += 1;
+ }
+ }
+ hy = hx&0x7f800000;
+ if(hy>=0x7f800000) return x+x; /* overflow */
+ 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)