Experimental version of mpfr

1 files changed, 116 insertions, 0 deletions

diff --git a/mpfr/cmp_ui.c b/mpfr/cmp_ui.c
new file mode 100644
index 000000000..48217a520
--- /dev/null
+++ b/mpfr/cmp_ui.c
@@ -0,0 +1,116 @@
+/* mpfr_cmp_ui -- compare a floating-point number with a machine integer
+
+Copyright (C) 1999 PolKA project, Inria Lorraine and Loria
+
+This file is part of the MPFR Library.
+
+The MPFR Library is free software; you can redistribute it and/or modify
+it under the terms of the GNU Library General Public License as published by
+the Free Software Foundation; either version 2 of the License, or (at your
+option) any later version.
+
+The MPFR Library is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
+License for more details.
+
+You should have received a copy of the GNU Library General Public License
+along with the MPFR Library; see the file COPYING.LIB.  If not, write to
+the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+MA 02111-1307, USA. */
+
+#include <stdio.h>
+#include "gmp.h"
+#include "gmp-impl.h"
+#include "longlong.h"
+#include "mpfr.h"
+
+/* returns a positive value if b>i*2^f,
+           a negative value if b<i*2^f,
+           zero if b=i*2^f
+*/
+
+int 
+#if __STDC__
+mpfr_cmp_ui_2exp ( mpfr_srcptr b, unsigned long int i, int f )
+#else
+mpfr_cmp_ui_2exp (b, i, f)
+     mpfr_srcptr b; 
+     unsigned long int i; 
+     int f; 
+#endif
+{
+  int e, k, bn; mp_limb_t c, *bp;
+
+  if (SIGN(b)<0) return -1;
+  else if (!NOTZERO(b)) return((i) ? -1 : 0);
+  else { /* b>0 */
+    e = EXP(b); /* 2^(e-1) <= b < 2^e */
+    if (e>f+mp_bits_per_limb) return 1;
+
+    c = (mp_limb_t) i;
+    count_leading_zeros(k, c);
+    k = f+mp_bits_per_limb - k; /* 2^(k-1) <= i*2^f < 2^k */
+    if (k!=e) return (e-k);
+
+    /* now k=e */
+    c <<= (f+mp_bits_per_limb-k);
+    bn = (PREC(b)-1)/mp_bits_per_limb;
+    bp = MANT(b) + bn;
+    if (*bp>c) return 1;
+    else if (*bp<c) return -1;
+
+    /* most significant limbs agree, check remaining limbs from b */
+    while (--bn>=0)
+      if (*--bp) return 1;
+    return 0;
+  }
+}
+
+/* returns a positive value if b>i*2^f,
+           a negative value if b<i*2^f,
+           zero if b=i*2^f 
+*/
+
+int 
+#if __STDC__
+mpfr_cmp_si_2exp ( mpfr_srcptr b, long int i, int f )
+#else
+mpfr_cmp_si_2exp(b, i, f)
+     mpfr_srcptr b; 
+     long int i; 
+     int f; 
+#endif
+{
+  int e, k, bn, si; mp_limb_t c, *bp;
+
+  si = (i<0) ? -1 : 1; /* sign of i */
+  if (SIGN(b)*i<0) return SIGN(b); /* both signs differ */
+  else if (!NOTZERO(b) || (i==0)) { /* one is zero */
+    if (i==0) return ((NOTZERO(b)) ? SIGN(b) : 0);
+    else return si; /* b is zero */
+      
+  }
+  else { /* b and i are of same sign */
+    e = EXP(b); /* 2^(e-1) <= b < 2^e */
+    if (e>f+mp_bits_per_limb) return si;
+
+    c = (mp_limb_t) ((i<0) ? -i : i);
+    count_leading_zeros(k, c);
+    k = f+mp_bits_per_limb - k; /* 2^(k-1) <= i*2^f < 2^k */
+    if (k!=e) return (si*(e-k));
+
+    /* now k=e */
+    c <<= (f+mp_bits_per_limb-k);
+    bn = (PREC(b)-1)/mp_bits_per_limb;
+    bp = MANT(b) + bn;
+    if (*bp>c) return si;
+    else if (*bp<c) return -si;
+
+    /* most significant limbs agree, check remaining limbs from b */
+    while (--bn>=0)
+      if (*--bp) return si;
+    return 0;
+  }
+}
+