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authorUlrich Drepper <drepper@redhat.com>2002-02-28 19:38:21 +0000
committerUlrich Drepper <drepper@redhat.com>2002-02-28 19:38:21 +0000
commit9321beea94daa4b9679099e0fc092ab1845a507d (patch)
tree6ce7a5b319ca56df1094aaf649aaff0bb41e393e /sysdeps/wordsize-32/divdi3.c
parent896167225ef6e3c5f780584e75cde2e8f253c038 (diff)
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Update.
2002-02-28  Jakub Jelinek  <jakub@redhat.com>

	* sysdeps/i386/Makefile (sysdep_routines): Add
	divdi3 in csu dir.
	(shared-only-routines): Likewise.
	* sysdeps/m68k/Makefile (sysdep_routines): Likewise.
	(shared-only-routines): Likewise.
	* sysdeps/s390/s390-32/Makefile (sysdep_routines): Likewise.
	(shared-only-routines): Likewise.
	* sysdeps/wordsize-32/divdi3.c: New file.
Diffstat (limited to 'sysdeps/wordsize-32/divdi3.c')
-rw-r--r--sysdeps/wordsize-32/divdi3.c327
1 files changed, 327 insertions, 0 deletions
diff --git a/sysdeps/wordsize-32/divdi3.c b/sysdeps/wordsize-32/divdi3.c
new file mode 100644
index 0000000000..7929e3019c
--- /dev/null
+++ b/sysdeps/wordsize-32/divdi3.c
@@ -0,0 +1,327 @@
+/* 64-bit multiplication and division
+   Copyright (C) 1989, 1992-1999, 2000, 2001, 2002
+   Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <endian.h>
+#include <stdlib.h>
+#include <bits/wordsize.h>
+
+#if __WORDSIZE != 32
+#error This is for 32-bit targets only
+#endif
+
+typedef unsigned int UQItype	__attribute__ ((mode (QI)));
+typedef          int SItype	__attribute__ ((mode (SI)));
+typedef unsigned int USItype	__attribute__ ((mode (SI)));
+typedef          int DItype	__attribute__ ((mode (DI)));
+typedef unsigned int UDItype	__attribute__ ((mode (DI)));
+#define Wtype SItype
+#define HWtype SItype
+#define DWtype DItype
+#define UWtype USItype
+#define UHWtype USItype
+#define UDWtype UDItype
+#define W_TYPE_SIZE 32
+
+#include <stdlib/longlong.h>
+
+#if __BYTE_ORDER == __BIG_ENDIAN
+struct DWstruct { Wtype high, low;};
+#elif __BYTE_ORDER == __LITTLE_ENDIAN
+struct DWstruct { Wtype low, high;};
+#else
+#error Unhandled endianity
+#endif
+typedef union { struct DWstruct s; DWtype ll; } DWunion;
+
+static UDWtype
+__udivmoddi4 (UDWtype n, UDWtype d, UDWtype *rp)
+{
+  DWunion ww;
+  DWunion nn, dd;
+  DWunion rr;
+  UWtype d0, d1, n0, n1, n2;
+  UWtype q0, q1;
+  UWtype b, bm;
+
+  nn.ll = n;
+  dd.ll = d;
+
+  d0 = dd.s.low;
+  d1 = dd.s.high;
+  n0 = nn.s.low;
+  n1 = nn.s.high;
+
+#if !UDIV_NEEDS_NORMALIZATION
+  if (d1 == 0)
+    {
+      if (d0 > n1)
+	{
+	  /* 0q = nn / 0D */
+
+	  udiv_qrnnd (q0, n0, n1, n0, d0);
+	  q1 = 0;
+
+	  /* Remainder in n0.  */
+	}
+      else
+	{
+	  /* qq = NN / 0d */
+
+	  if (d0 == 0)
+	    d0 = 1 / d0;	/* Divide intentionally by zero.  */
+
+	  udiv_qrnnd (q1, n1, 0, n1, d0);
+	  udiv_qrnnd (q0, n0, n1, n0, d0);
+
+	  /* Remainder in n0.  */
+	}
+
+      if (rp != 0)
+	{
+	  rr.s.low = n0;
+	  rr.s.high = 0;
+	  *rp = rr.ll;
+	}
+    }
+
+#else /* UDIV_NEEDS_NORMALIZATION */
+
+  if (d1 == 0)
+    {
+      if (d0 > n1)
+	{
+	  /* 0q = nn / 0D */
+
+	  count_leading_zeros (bm, d0);
+
+	  if (bm != 0)
+	    {
+	      /* Normalize, i.e. make the most significant bit of the
+		 denominator set.  */
+
+	      d0 = d0 << bm;
+	      n1 = (n1 << bm) | (n0 >> (W_TYPE_SIZE - bm));
+	      n0 = n0 << bm;
+	    }
+
+	  udiv_qrnnd (q0, n0, n1, n0, d0);
+	  q1 = 0;
+
+	  /* Remainder in n0 >> bm.  */
+	}
+      else
+	{
+	  /* qq = NN / 0d */
+
+	  if (d0 == 0)
+	    d0 = 1 / d0;	/* Divide intentionally by zero.  */
+
+	  count_leading_zeros (bm, d0);
+
+	  if (bm == 0)
+	    {
+	      /* From (n1 >= d0) /\ (the most significant bit of d0 is set),
+		 conclude (the most significant bit of n1 is set) /\ (the
+		 leading quotient digit q1 = 1).
+
+		 This special case is necessary, not an optimization.
+		 (Shifts counts of W_TYPE_SIZE are undefined.)  */
+
+	      n1 -= d0;
+	      q1 = 1;
+	    }
+	  else
+	    {
+	      /* Normalize.  */
+
+	      b = W_TYPE_SIZE - bm;
+
+	      d0 = d0 << bm;
+	      n2 = n1 >> b;
+	      n1 = (n1 << bm) | (n0 >> b);
+	      n0 = n0 << bm;
+
+	      udiv_qrnnd (q1, n1, n2, n1, d0);
+	    }
+
+	  /* n1 != d0...  */
+
+	  udiv_qrnnd (q0, n0, n1, n0, d0);
+
+	  /* Remainder in n0 >> bm.  */
+	}
+
+      if (rp != 0)
+	{
+	  rr.s.low = n0 >> bm;
+	  rr.s.high = 0;
+	  *rp = rr.ll;
+	}
+    }
+#endif /* UDIV_NEEDS_NORMALIZATION */
+
+  else
+    {
+      if (d1 > n1)
+	{
+	  /* 00 = nn / DD */
+
+	  q0 = 0;
+	  q1 = 0;
+
+	  /* Remainder in n1n0.  */
+	  if (rp != 0)
+	    {
+	      rr.s.low = n0;
+	      rr.s.high = n1;
+	      *rp = rr.ll;
+	    }
+	}
+      else
+	{
+	  /* 0q = NN / dd */
+
+	  count_leading_zeros (bm, d1);
+	  if (bm == 0)
+	    {
+	      /* From (n1 >= d1) /\ (the most significant bit of d1 is set),
+		 conclude (the most significant bit of n1 is set) /\ (the
+		 quotient digit q0 = 0 or 1).
+
+		 This special case is necessary, not an optimization.  */
+
+	      /* The condition on the next line takes advantage of that
+		 n1 >= d1 (true due to program flow).  */
+	      if (n1 > d1 || n0 >= d0)
+		{
+		  q0 = 1;
+		  sub_ddmmss (n1, n0, n1, n0, d1, d0);
+		}
+	      else
+		q0 = 0;
+
+	      q1 = 0;
+
+	      if (rp != 0)
+		{
+		  rr.s.low = n0;
+		  rr.s.high = n1;
+		  *rp = rr.ll;
+		}
+	    }
+	  else
+	    {
+	      UWtype m1, m0;
+	      /* Normalize.  */
+
+	      b = W_TYPE_SIZE - bm;
+
+	      d1 = (d1 << bm) | (d0 >> b);
+	      d0 = d0 << bm;
+	      n2 = n1 >> b;
+	      n1 = (n1 << bm) | (n0 >> b);
+	      n0 = n0 << bm;
+
+	      udiv_qrnnd (q0, n1, n2, n1, d1);
+	      umul_ppmm (m1, m0, q0, d0);
+
+	      if (m1 > n1 || (m1 == n1 && m0 > n0))
+		{
+		  q0--;
+		  sub_ddmmss (m1, m0, m1, m0, d1, d0);
+		}
+
+	      q1 = 0;
+
+	      /* Remainder in (n1n0 - m1m0) >> bm.  */
+	      if (rp != 0)
+		{
+		  sub_ddmmss (n1, n0, n1, n0, m1, m0);
+		  rr.s.low = (n1 << b) | (n0 >> bm);
+		  rr.s.high = n1 >> bm;
+		  *rp = rr.ll;
+		}
+	    }
+	}
+    }
+
+  ww.s.low = q0;
+  ww.s.high = q1;
+  return ww.ll;
+}
+
+DWtype
+__divdi3 (DWtype u, DWtype v)
+{
+  Wtype c = 0;
+  DWtype w;
+
+  if (u < 0)
+    {
+      c = ~c;
+      u = -u;
+    }
+  if (v < 0)
+    {
+      c = ~c;
+      v = -v;
+    }
+  w = __udivmoddi4 (u, v, NULL);
+  if (c)
+    w = -w;
+  return w;
+}
+
+DWtype
+__moddi3 (DWtype u, DWtype v)
+{
+  Wtype c = 0;
+  DWtype w;
+
+  if (u < 0)
+    {
+      c = ~c;
+      u = -u;
+    }
+  if (v < 0)
+    {
+      c = ~c;
+      v = -v;
+    }
+  __udivmoddi4 (u, v, &w);
+  if (c)
+    w = -w;
+  return w;
+}
+
+UDWtype
+__udivdi3 (UDWtype u, UDWtype v)
+{
+  return __udivmoddi4 (u, v, NULL);
+}
+
+UDWtype
+__umoddi3 (UDWtype u, UDWtype v)
+{
+  UDWtype w;
+
+  __udivmoddi4 (u, v, &w);
+  return w;
+}