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Index: dietlibc-0.31/libm/ceil.c
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ dietlibc-0.31/libm/ceil.c	2009-02-01 02:54:28.533109301 +0100
@@ -0,0 +1,92 @@
+/* @(#)s_ceil.c 5.1 93/09/24 */
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/*
+ * ceil(x)
+ * Return x rounded toward -inf to integral value
+ * Method:
+ *	Bit twiddling.
+ * Exception:
+ *	Inexact flag raised if x not equal to ceil(x).
+ */
+
+#include <math.h>
+
+typedef union {
+  double value;
+  struct {
+    unsigned int lsw;
+    unsigned int msw;
+  } parts;
+} ieee_double_shape_type;
+
+/* Get two 32 bit ints from a double.  */
+
+#define EXTRACT_WORDS(ix0,ix1,d)                                \
+do {                                                            \
+  ieee_double_shape_type ew_u;                                  \
+  ew_u.value = (d);                                             \
+  (ix0) = ew_u.parts.msw;                                       \
+  (ix1) = ew_u.parts.lsw;                                       \
+} while (0)
+
+#define INSERT_WORDS(d,ix0,ix1)                                 \
+do {                                                            \
+  ieee_double_shape_type iw_u;                                  \
+  iw_u.parts.msw = (ix0);                                       \
+  iw_u.parts.lsw = (ix1);                                       \
+  (d) = iw_u.value;                                             \
+} while (0)
+
+static const double huge = 1.0e300;
+
+double ceil(double x)
+{
+	int i0,i1,j0;
+	unsigned int i,j;
+	EXTRACT_WORDS(i0,i1,x);
+	j0 = ((i0>>20)&0x7ff)-0x3ff;
+	if(j0<20) {
+	    if(j0<0) { 	/* raise inexact if x != 0 */
+		if(huge+x>0.0) {/* return 0*sign(x) if |x|<1 */
+		    if(i0<0) {i0=0x80000000;i1=0;}
+		    else if((i0|i1)!=0) { i0=0x3ff00000;i1=0;}
+		}
+	    } else {
+		i = (0x000fffff)>>j0;
+		if(((i0&i)|i1)==0) return x; /* x is integral */
+		if(huge+x>0.0) {	/* raise inexact flag */
+		    if(i0>0) i0 += (0x00100000)>>j0;
+		    i0 &= (~i); i1=0;
+		}
+	    }
+	} else if (j0>51) {
+	    if(j0==0x400) return x+x;	/* inf or NaN */
+	    else return x;		/* x is integral */
+	} else {
+	    i = ((unsigned int)(0xffffffff))>>(j0-20);
+	    if((i1&i)==0) return x;	/* x is integral */
+	    if(huge+x>0.0) { 		/* raise inexact flag */
+		if(i0>0) {
+		    if(j0==20) i0+=1;
+		    else {
+			j = i1 + (1<<(52-j0));
+			if(j<i1) i0+=1;	/* got a carry */
+			i1 = j;
+		    }
+		}
+		i1 &= (~i);
+	    }
+	}
+	INSERT_WORDS(x,i0,i1);
+	return x;
+}