Update.

1999-12-29  Ulrich Drepper  <drepper@cygnus.com>

	* soft-fp/*: Tons of new files to implement floating-point arithmetic
	in software.
	Contributed by  Richard Henderson, Jakub Jelinek and others.

1 files changed, 661 insertions, 0 deletions

diff --git a/soft-fp/op-4.h b/soft-fp/op-4.h
new file mode 100644
index 0000000000..f5235f5d97
--- /dev/null
+++ b/soft-fp/op-4.h
@@ -0,0 +1,661 @@
+/* Software floating-point emulation.
+   Basic four-word fraction declaration and manipulation.
+   Copyright (C) 1997,1998,1999 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Richard Henderson (rth@cygnus.com),
+		  Jakub Jelinek (jj@ultra.linux.cz),
+		  David S. Miller (davem@redhat.com) and
+		  Peter Maydell (pmaydell@chiark.greenend.org.uk).
+
+   The GNU C 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 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C 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.  */
+
+#define _FP_FRAC_DECL_4(X)	_FP_W_TYPE X##_f[4]
+#define _FP_FRAC_COPY_4(D,S)			\
+  (D##_f[0] = S##_f[0], D##_f[1] = S##_f[1],	\
+   D##_f[2] = S##_f[2], D##_f[3] = S##_f[3])
+#define _FP_FRAC_SET_4(X,I)	__FP_FRAC_SET_4(X, I)
+#define _FP_FRAC_HIGH_4(X)	(X##_f[3])
+#define _FP_FRAC_LOW_4(X)	(X##_f[0])
+#define _FP_FRAC_WORD_4(X,w)	(X##_f[w])
+
+#define _FP_FRAC_SLL_4(X,N)						\
+  do {									\
+    _FP_I_TYPE _up, _down, _skip, _i;					\
+    _skip = (N) / _FP_W_TYPE_SIZE;					\
+    _up = (N) % _FP_W_TYPE_SIZE;					\
+    _down = _FP_W_TYPE_SIZE - _up;					\
+    if (!_up)								\
+      for (_i = 3; _i >= _skip; --_i)					\
+	X##_f[_i] = X##_f[_i-_skip];					\
+    else								\
+      {									\
+	for (_i = 3; _i > _skip; --_i)					\
+	  X##_f[_i] = X##_f[_i-_skip] << _up				\
+		      | X##_f[_i-_skip-1] >> _down;			\
+	X##_f[_i--] = X##_f[0] << _up; 					\
+      }									\
+    for (; _i >= 0; --_i)						\
+      X##_f[_i] = 0;							\
+  } while (0)
+
+/* This one was broken too */
+#define _FP_FRAC_SRL_4(X,N)						\
+  do {									\
+    _FP_I_TYPE _up, _down, _skip, _i;					\
+    _skip = (N) / _FP_W_TYPE_SIZE;					\
+    _down = (N) % _FP_W_TYPE_SIZE;					\
+    _up = _FP_W_TYPE_SIZE - _down;					\
+    if (!_down)								\
+      for (_i = 0; _i <= 3-_skip; ++_i)					\
+	X##_f[_i] = X##_f[_i+_skip];					\
+    else								\
+      {									\
+	for (_i = 0; _i < 3-_skip; ++_i)				\
+	  X##_f[_i] = X##_f[_i+_skip] >> _down				\
+		      | X##_f[_i+_skip+1] << _up;			\
+	X##_f[_i++] = X##_f[3] >> _down;				\
+      }									\
+    for (; _i < 4; ++_i)						\
+      X##_f[_i] = 0;							\
+  } while (0)
+
+
+/* Right shift with sticky-lsb. 
+ * What this actually means is that we do a standard right-shift,
+ * but that if any of the bits that fall off the right hand side
+ * were one then we always set the LSbit.
+ */
+#define _FP_FRAC_SRS_4(X,N,size)					\
+  do {									\
+    _FP_I_TYPE _up, _down, _skip, _i;					\
+    _FP_W_TYPE _s;							\
+    _skip = (N) / _FP_W_TYPE_SIZE;					\
+    _down = (N) % _FP_W_TYPE_SIZE;					\
+    _up = _FP_W_TYPE_SIZE - _down;					\
+    for (_s = _i = 0; _i < _skip; ++_i)					\
+      _s |= X##_f[_i];							\
+    _s |= X##_f[_i] << _up;						\
+/* s is now != 0 if we want to set the LSbit */				\
+    if (!_down)								\
+      for (_i = 0; _i <= 3-_skip; ++_i)					\
+	X##_f[_i] = X##_f[_i+_skip];					\
+    else								\
+      {									\
+	for (_i = 0; _i < 3-_skip; ++_i)				\
+	  X##_f[_i] = X##_f[_i+_skip] >> _down				\
+		      | X##_f[_i+_skip+1] << _up;			\
+	X##_f[_i++] = X##_f[3] >> _down;				\
+      }									\
+    for (; _i < 4; ++_i)						\
+      X##_f[_i] = 0;							\
+    /* don't fix the LSB until the very end when we're sure f[0] is stable */	\
+    X##_f[0] |= (_s != 0);						\
+  } while (0)
+
+#define _FP_FRAC_ADD_4(R,X,Y)						\
+  __FP_FRAC_ADD_4(R##_f[3], R##_f[2], R##_f[1], R##_f[0],		\
+		  X##_f[3], X##_f[2], X##_f[1], X##_f[0],		\
+		  Y##_f[3], Y##_f[2], Y##_f[1], Y##_f[0])
+
+#define _FP_FRAC_SUB_4(R,X,Y)						\
+  __FP_FRAC_SUB_4(R##_f[3], R##_f[2], R##_f[1], R##_f[0],		\
+		  X##_f[3], X##_f[2], X##_f[1], X##_f[0],		\
+		  Y##_f[3], Y##_f[2], Y##_f[1], Y##_f[0])
+
+#define _FP_FRAC_DEC_4(X,Y)						\
+  __FP_FRAC_DEC_4(X##_f[3], X##_f[2], X##_f[1], X##_f[0],		\
+		  Y##_f[3], Y##_f[2], Y##_f[1], Y##_f[0])
+
+#define _FP_FRAC_ADDI_4(X,I)						\
+  __FP_FRAC_ADDI_4(X##_f[3], X##_f[2], X##_f[1], X##_f[0], I)
+
+#define _FP_ZEROFRAC_4  0,0,0,0
+#define _FP_MINFRAC_4   0,0,0,1
+#define _FP_MAXFRAC_4	(~(_FP_WS_TYPE)0), (~(_FP_WS_TYPE)0), (~(_FP_WS_TYPE)0), (~(_FP_WS_TYPE)0)
+
+#define _FP_FRAC_ZEROP_4(X)     ((X##_f[0] | X##_f[1] | X##_f[2] | X##_f[3]) == 0)
+#define _FP_FRAC_NEGP_4(X)      ((_FP_WS_TYPE)X##_f[3] < 0)
+#define _FP_FRAC_OVERP_4(fs,X)  (_FP_FRAC_HIGH_##fs(X) & _FP_OVERFLOW_##fs)
+
+#define _FP_FRAC_EQ_4(X,Y)				\
+ (X##_f[0] == Y##_f[0] && X##_f[1] == Y##_f[1]		\
+  && X##_f[2] == Y##_f[2] && X##_f[3] == Y##_f[3])
+
+#define _FP_FRAC_GT_4(X,Y)				\
+ (X##_f[3] > Y##_f[3] ||				\
+  (X##_f[3] == Y##_f[3] && (X##_f[2] > Y##_f[2] ||	\
+   (X##_f[2] == Y##_f[2] && (X##_f[1] > Y##_f[1] ||	\
+    (X##_f[1] == Y##_f[1] && X##_f[0] > Y##_f[0])	\
+   ))							\
+  ))							\
+ )
+
+#define _FP_FRAC_GE_4(X,Y)				\
+ (X##_f[3] > Y##_f[3] ||				\
+  (X##_f[3] == Y##_f[3] && (X##_f[2] > Y##_f[2] ||	\
+   (X##_f[2] == Y##_f[2] && (X##_f[1] > Y##_f[1] ||	\
+    (X##_f[1] == Y##_f[1] && X##_f[0] >= Y##_f[0])	\
+   ))							\
+  ))							\
+ )
+
+
+#define _FP_FRAC_CLZ_4(R,X)		\
+  do {					\
+    if (X##_f[3])			\
+    {					\
+	__FP_CLZ(R,X##_f[3]);		\
+    }					\
+    else if (X##_f[2])			\
+    {					\
+	__FP_CLZ(R,X##_f[2]);		\
+	R += _FP_W_TYPE_SIZE;		\
+    }					\
+    else if (X##_f[1])			\
+    {					\
+	__FP_CLZ(R,X##_f[2]);		\
+	R += _FP_W_TYPE_SIZE*2;		\
+    }					\
+    else				\
+    {					\
+	__FP_CLZ(R,X##_f[0]);		\
+	R += _FP_W_TYPE_SIZE*3;		\
+    }					\
+  } while(0)
+
+
+#define _FP_UNPACK_RAW_4(fs, X, val)				\
+  do {								\
+    union _FP_UNION_##fs _flo; _flo.flt = (val);		\
+    X##_f[0] = _flo.bits.frac0;					\
+    X##_f[1] = _flo.bits.frac1;					\
+    X##_f[2] = _flo.bits.frac2;					\
+    X##_f[3] = _flo.bits.frac3;					\
+    X##_e  = _flo.bits.exp;					\
+    X##_s  = _flo.bits.sign;					\
+  } while (0)
+
+#define _FP_UNPACK_RAW_4_P(fs, X, val)				\
+  do {								\
+    union _FP_UNION_##fs *_flo =				\
+      (union _FP_UNION_##fs *)(val);				\
+								\
+    X##_f[0] = _flo->bits.frac0;				\
+    X##_f[1] = _flo->bits.frac1;				\
+    X##_f[2] = _flo->bits.frac2;				\
+    X##_f[3] = _flo->bits.frac3;				\
+    X##_e  = _flo->bits.exp;					\
+    X##_s  = _flo->bits.sign;					\
+  } while (0)
+
+#define _FP_PACK_RAW_4(fs, val, X)				\
+  do {								\
+    union _FP_UNION_##fs _flo;					\
+    _flo.bits.frac0 = X##_f[0];					\
+    _flo.bits.frac1 = X##_f[1];					\
+    _flo.bits.frac2 = X##_f[2];					\
+    _flo.bits.frac3 = X##_f[3];					\
+    _flo.bits.exp   = X##_e;					\
+    _flo.bits.sign  = X##_s;					\
+    (val) = _flo.flt;				   		\
+  } while (0)
+
+#define _FP_PACK_RAW_4_P(fs, val, X)				\
+  do {								\
+    union _FP_UNION_##fs *_flo =				\
+      (union _FP_UNION_##fs *)(val);				\
+								\
+    _flo->bits.frac0 = X##_f[0];				\
+    _flo->bits.frac1 = X##_f[1];				\
+    _flo->bits.frac2 = X##_f[2];				\
+    _flo->bits.frac3 = X##_f[3];				\
+    _flo->bits.exp   = X##_e;					\
+    _flo->bits.sign  = X##_s;					\
+  } while (0)
+
+/*
+ * Multiplication algorithms:
+ */
+
+/* Given a 1W * 1W => 2W primitive, do the extended multiplication.  */
+
+#define _FP_MUL_MEAT_4_wide(wfracbits, R, X, Y, doit)			    \
+  do {									    \
+    _FP_FRAC_DECL_8(_z); _FP_FRAC_DECL_2(_b); _FP_FRAC_DECL_2(_c);	    \
+    _FP_FRAC_DECL_2(_d); _FP_FRAC_DECL_2(_e); _FP_FRAC_DECL_2(_f);	    \
+									    \
+    doit(_FP_FRAC_WORD_8(_z,1), _FP_FRAC_WORD_8(_z,0), X##_f[0], Y##_f[0]); \
+    doit(_b_f1, _b_f0, X##_f[0], Y##_f[1]);				    \
+    doit(_c_f1, _c_f0, X##_f[1], Y##_f[0]);				    \
+    doit(_d_f1, _d_f0, X##_f[1], Y##_f[1]);				    \
+    doit(_e_f1, _e_f0, X##_f[0], Y##_f[2]);				    \
+    doit(_f_f1, _f_f0, X##_f[2], Y##_f[0]);				    \
+    __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,3),_FP_FRAC_WORD_8(_z,2),	    \
+		    _FP_FRAC_WORD_8(_z,1), 0,_b_f1,_b_f0,		    \
+		    0,0,_FP_FRAC_WORD_8(_z,1));				    \
+    __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,3),_FP_FRAC_WORD_8(_z,2),	    \
+		    _FP_FRAC_WORD_8(_z,1), 0,_c_f1,_c_f0,		    \
+		    _FP_FRAC_WORD_8(_z,3),_FP_FRAC_WORD_8(_z,2),	    \
+		    _FP_FRAC_WORD_8(_z,1));				    \
+    __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,4),_FP_FRAC_WORD_8(_z,3),	    \
+		    _FP_FRAC_WORD_8(_z,2), 0,_d_f1,_d_f0,		    \
+		    0,_FP_FRAC_WORD_8(_z,3),_FP_FRAC_WORD_8(_z,2));	    \
+    __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,4),_FP_FRAC_WORD_8(_z,3),	    \
+		    _FP_FRAC_WORD_8(_z,2), 0,_e_f1,_e_f0,		    \
+		    _FP_FRAC_WORD_8(_z,4),_FP_FRAC_WORD_8(_z,3),	    \
+		    _FP_FRAC_WORD_8(_z,2));				    \
+    __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,4),_FP_FRAC_WORD_8(_z,3),	    \
+		    _FP_FRAC_WORD_8(_z,2), 0,_f_f1,_f_f0,		    \
+		    _FP_FRAC_WORD_8(_z,4),_FP_FRAC_WORD_8(_z,3),	    \
+		    _FP_FRAC_WORD_8(_z,2));				    \
+    doit(_b_f1, _b_f0, X##_f[0], Y##_f[3]);				    \
+    doit(_c_f1, _c_f0, X##_f[3], Y##_f[0]);				    \
+    doit(_d_f1, _d_f0, X##_f[1], Y##_f[2]);				    \
+    doit(_e_f1, _e_f0, X##_f[2], Y##_f[1]);				    \
+    __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4),	    \
+		    _FP_FRAC_WORD_8(_z,3), 0,_b_f1,_b_f0,		    \
+		    0,_FP_FRAC_WORD_8(_z,4),_FP_FRAC_WORD_8(_z,3));	    \
+    __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4),	    \
+		    _FP_FRAC_WORD_8(_z,3), 0,_c_f1,_c_f0,		    \
+		    _FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4),	    \
+		    _FP_FRAC_WORD_8(_z,3));				    \
+    __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4),	    \
+		    _FP_FRAC_WORD_8(_z,3), 0,_d_f1,_d_f0,		    \
+		    _FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4),	    \
+		    _FP_FRAC_WORD_8(_z,3));				    \
+    __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4),	    \
+		    _FP_FRAC_WORD_8(_z,3), 0,_e_f1,_e_f0,		    \
+		    _FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4),	    \
+		    _FP_FRAC_WORD_8(_z,3));				    \
+    doit(_b_f1, _b_f0, X##_f[2], Y##_f[2]);				    \
+    doit(_c_f1, _c_f0, X##_f[1], Y##_f[3]);				    \
+    doit(_d_f1, _d_f0, X##_f[3], Y##_f[1]);				    \
+    doit(_e_f1, _e_f0, X##_f[2], Y##_f[3]);				    \
+    doit(_f_f1, _f_f0, X##_f[3], Y##_f[2]);				    \
+    __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,6),_FP_FRAC_WORD_8(_z,5),	    \
+		    _FP_FRAC_WORD_8(_z,4), 0,_b_f1,_b_f0,		    \
+		    0,_FP_FRAC_WORD_8(_z,5),_FP_FRAC_WORD_8(_z,4));	    \
+    __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,6),_FP_FRAC_WORD_8(_z,5),	    \
+		    _FP_FRAC_WORD_8(_z,4), 0,_c_f1,_c_f0,		    \
+		    _FP_FRAC_WORD_8(_z,6),_FP_FRAC_WORD_8(_z,5),	    \
+		    _FP_FRAC_WORD_8(_z,4));				    \
+    __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,6),_FP_FRAC_WORD_8(_z,5),	    \
+		    _FP_FRAC_WORD_8(_z,4), 0,_d_f1,_d_f0,		    \
+		    _FP_FRAC_WORD_8(_z,6),_FP_FRAC_WORD_8(_z,5),	    \
+		    _FP_FRAC_WORD_8(_z,4));				    \
+    __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,7),_FP_FRAC_WORD_8(_z,6),	    \
+		    _FP_FRAC_WORD_8(_z,5), 0,_e_f1,_e_f0,		    \
+		    0,_FP_FRAC_WORD_8(_z,6),_FP_FRAC_WORD_8(_z,5));	    \
+    __FP_FRAC_ADD_3(_FP_FRAC_WORD_8(_z,7),_FP_FRAC_WORD_8(_z,6),	    \
+		    _FP_FRAC_WORD_8(_z,5), 0,_f_f1,_f_f0,		    \
+		    _FP_FRAC_WORD_8(_z,7),_FP_FRAC_WORD_8(_z,6),	    \
+		    _FP_FRAC_WORD_8(_z,5));				    \
+    doit(_b_f1, _b_f0, X##_f[3], Y##_f[3]);				    \
+    __FP_FRAC_ADD_2(_FP_FRAC_WORD_8(_z,7),_FP_FRAC_WORD_8(_z,6),	    \
+		    _b_f1,_b_f0,					    \
+		    _FP_FRAC_WORD_8(_z,7),_FP_FRAC_WORD_8(_z,6));	    \
+									    \
+    /* Normalize since we know where the msb of the multiplicands	    \
+       were (bit B), we know that the msb of the of the product is	    \
+       at either 2B or 2B-1.  */					    \
+    _FP_FRAC_SRS_8(_z, wfracbits-1, 2*wfracbits);			    \
+    __FP_FRAC_SET_4(R, _FP_FRAC_WORD_8(_z,3), _FP_FRAC_WORD_8(_z,2),	    \
+		    _FP_FRAC_WORD_8(_z,1), _FP_FRAC_WORD_8(_z,0));	    \
+  } while (0)
+
+#define _FP_MUL_MEAT_4_gmp(wfracbits, R, X, Y)				    \
+  do {									    \
+    _FP_FRAC_DECL_8(_z);						    \
+									    \
+    mpn_mul_n(_z_f, _x_f, _y_f, 4);					    \
+									    \
+    /* Normalize since we know where the msb of the multiplicands	    \
+       were (bit B), we know that the msb of the of the product is	    \
+       at either 2B or 2B-1.  */					    \
+    _FP_FRAC_SRS_8(_z, wfracbits-1, 2*wfracbits);	 		    \
+    __FP_FRAC_SET_4(R, _FP_FRAC_WORD_8(_z,3), _FP_FRAC_WORD_8(_z,2),	    \
+		    _FP_FRAC_WORD_8(_z,1), _FP_FRAC_WORD_8(_z,0));	    \
+  } while (0)
+
+/*
+ * Helper utility for _FP_DIV_MEAT_4_udiv:
+ * pppp = m * nnn
+ */
+#define umul_ppppmnnn(p3,p2,p1,p0,m,n2,n1,n0)				    \
+  do {									    \
+    UWtype _t;								    \
+    umul_ppmm(p1,p0,m,n0);						    \
+    umul_ppmm(p2,_t,m,n1);						    \
+    __FP_FRAC_ADDI_2(p2,p1,_t);						    \
+    umul_ppmm(p3,_t,m,n2);						    \
+    __FP_FRAC_ADDI_2(p3,p2,_t);						    \
+  } while (0)
+
+/*
+ * Division algorithms:
+ */
+
+#define _FP_DIV_MEAT_4_udiv(fs, R, X, Y)				    \
+  do {									    \
+    int _i;								    \
+    _FP_FRAC_DECL_4(_n); _FP_FRAC_DECL_4(_m);				    \
+    _FP_FRAC_SET_4(_n, _FP_ZEROFRAC_4);					    \
+    if (_FP_FRAC_GT_4(X, Y))						    \
+      {									    \
+	_n_f[3] = X##_f[0] << (_FP_W_TYPE_SIZE - 1);			    \
+	_FP_FRAC_SRL_4(X, 1);						    \
+      }									    \
+    else								    \
+      R##_e--;								    \
+									    \
+    /* Normalize, i.e. make the most significant bit of the 		    \
+       denominator set. */						    \
+    _FP_FRAC_SLL_4(Y, _FP_WFRACXBITS_##fs);				    \
+									    \
+    for (_i = 3; ; _i--)						    \
+      {									    \
+        if (X##_f[3] == Y##_f[3])					    \
+          {								    \
+            /* This is a special case, not an optimization		    \
+               (X##_f[3]/Y##_f[3] would not fit into UWtype).		    \
+               As X## is guaranteed to be < Y,  R##_f[_i] can be either	    \
+               (UWtype)-1 or (UWtype)-2.  */				    \
+            R##_f[_i] = -1;						    \
+            if (!_i)							    \
+	      break;							    \
+            __FP_FRAC_SUB_4(X##_f[3], X##_f[2], X##_f[1], X##_f[0],	    \
+			    Y##_f[2], Y##_f[1], Y##_f[0], 0,		    \
+			    X##_f[2], X##_f[1], X##_f[0], _n_f[_i]);	    \
+            _FP_FRAC_SUB_4(X, Y, X);					    \
+            if (X##_f[3] > Y##_f[3])					    \
+              {								    \
+                R##_f[_i] = -2;						    \
+                _FP_FRAC_ADD_4(X, Y, X);				    \
+              }								    \
+          }								    \
+        else								    \
+          {								    \
+            udiv_qrnnd(R##_f[_i], X##_f[3], X##_f[3], X##_f[2], Y##_f[3]);  \
+            umul_ppppmnnn(_m_f[3], _m_f[2], _m_f[1], _m_f[0],		    \
+			  R##_f[_i], Y##_f[2], Y##_f[1], Y##_f[0]);	    \
+            X##_f[2] = X##_f[1];					    \
+            X##_f[1] = X##_f[0];					    \
+            X##_f[0] = _n_f[_i];					    \
+            if (_FP_FRAC_GT_4(_m, X))					    \
+              {								    \
+                R##_f[_i]--;						    \
+                _FP_FRAC_ADD_4(X, Y, X);				    \
+                if (_FP_FRAC_GE_4(X, Y) && _FP_FRAC_GT_4(_m, X))	    \
+                  {							    \
+		    R##_f[_i]--;					    \
+		    _FP_FRAC_ADD_4(X, Y, X);				    \
+                  }							    \
+              }								    \
+            _FP_FRAC_DEC_4(X, _m);					    \
+            if (!_i)							    \
+	      {								    \
+		if (!_FP_FRAC_EQ_4(X, _m))				    \
+		  R##_f[0] |= _FP_WORK_STICKY;				    \
+		break;							    \
+	      }								    \
+          }								    \
+      }									    \
+  } while (0)
+
+
+/*
+ * Square root algorithms:
+ * We have just one right now, maybe Newton approximation
+ * should be added for those machines where division is fast.
+ */
+ 
+#define _FP_SQRT_MEAT_4(R, S, T, X, q)				\
+  do {								\
+    while (q)							\
+      {								\
+	T##_f[3] = S##_f[3] + q;				\
+	if (T##_f[3] <= X##_f[3])				\
+	  {							\
+	    S##_f[3] = T##_f[3] + q;				\
+	    X##_f[3] -= T##_f[3];				\
+	    R##_f[3] += q;					\
+	  }							\
+	_FP_FRAC_SLL_4(X, 1);					\
+	q >>= 1;						\
+      }								\
+    q = (_FP_W_TYPE)1 << (_FP_W_TYPE_SIZE - 1);			\
+    while (q)							\
+      {								\
+	T##_f[2] = S##_f[2] + q;				\
+	T##_f[3] = S##_f[3];					\
+	if (T##_f[3] < X##_f[3] || 				\
+	    (T##_f[3] == X##_f[3] && T##_f[2] <= X##_f[2]))	\
+	  {							\
+	    S##_f[2] = T##_f[2] + q;				\
+	    S##_f[3] += (T##_f[2] > S##_f[2]);			\
+	    __FP_FRAC_DEC_2(X##_f[3], X##_f[2],			\
+			    T##_f[3], T##_f[2]);		\
+	    R##_f[2] += q;					\
+	  }							\
+	_FP_FRAC_SLL_4(X, 1);					\
+	q >>= 1;						\
+      }								\
+    q = (_FP_W_TYPE)1 << (_FP_W_TYPE_SIZE - 1);			\
+    while (q)							\
+      {								\
+	T##_f[1] = S##_f[1] + q;				\
+	T##_f[2] = S##_f[2];					\
+	T##_f[3] = S##_f[3];					\
+	if (T##_f[3] < X##_f[3] || 				\
+	    (T##_f[3] == X##_f[3] && (T##_f[2] < X##_f[2] ||	\
+	     (T##_f[2] == X##_f[2] && T##_f[1] <= X##_f[1]))))	\
+	  {							\
+	    S##_f[1] = T##_f[1] + q;				\
+	    S##_f[2] += (T##_f[1] > S##_f[1]);			\
+	    S##_f[3] += (T##_f[2] > S##_f[2]);			\
+	    __FP_FRAC_DEC_3(X##_f[3], X##_f[2], X##_f[1],	\
+	    		    T##_f[3], T##_f[2], T##_f[1]);	\
+	    R##_f[1] += q;					\
+	  }							\
+	_FP_FRAC_SLL_4(X, 1);					\
+	q >>= 1;						\
+      }								\
+    q = (_FP_W_TYPE)1 << (_FP_W_TYPE_SIZE - 1);			\
+    while (q != _FP_WORK_ROUND)					\
+      {								\
+	T##_f[0] = S##_f[0] + q;				\
+	T##_f[1] = S##_f[1];					\
+	T##_f[2] = S##_f[2];					\
+	T##_f[3] = S##_f[3];					\
+	if (_FP_FRAC_GE_4(X,T))					\
+	  {							\
+	    S##_f[0] = T##_f[0] + q;				\
+	    S##_f[1] += (T##_f[0] > S##_f[0]);			\
+	    S##_f[2] += (T##_f[1] > S##_f[1]);			\
+	    S##_f[3] += (T##_f[2] > S##_f[2]);			\
+	    _FP_FRAC_DEC_4(X, T);				\
+	    R##_f[0] += q;					\
+	  }							\
+	_FP_FRAC_SLL_4(X, 1);					\
+	q >>= 1;						\
+      }								\
+    if (!_FP_FRAC_ZEROP_4(X))					\
+      {								\
+	if (_FP_FRAC_GT_4(X,S))					\
+	  R##_f[0] |= _FP_WORK_ROUND;				\
+	R##_f[0] |= _FP_WORK_STICKY;				\
+      }								\
+  } while (0)
+
+
+/*
+ * Internals 
+ */
+
+#define __FP_FRAC_SET_4(X,I3,I2,I1,I0)					\
+  (X##_f[3] = I3, X##_f[2] = I2, X##_f[1] = I1, X##_f[0] = I0)
+
+#ifndef __FP_FRAC_ADD_3
+#define __FP_FRAC_ADD_3(r2,r1,r0,x2,x1,x0,y2,y1,y0)			\
+  (r0 = x0 + y0,							\
+   r1 = x1 + y1 + (r0 < x0),						\
+   r2 = x2 + y2 + (r1 < x1))
+#endif
+
+#ifndef __FP_FRAC_ADD_4
+#define __FP_FRAC_ADD_4(r3,r2,r1,r0,x3,x2,x1,x0,y3,y2,y1,y0)		\
+  (r0 = x0 + y0,							\
+   r1 = x1 + y1 + (r0 < x0),						\
+   r2 = x2 + y2 + (r1 < x1),						\
+   r3 = x3 + y3 + (r2 < x2))
+#endif
+
+#ifndef __FP_FRAC_SUB_3
+#define __FP_FRAC_SUB_3(r2,r1,r0,x2,x1,x0,y2,y1,y0)			\
+  (r0 = x0 - y0,							\
+   r1 = x1 - y1 - (r0 > x0),						\
+   r2 = x2 - y2 - (r1 > x1))
+#endif
+
+#ifndef __FP_FRAC_SUB_4
+#define __FP_FRAC_SUB_4(r3,r2,r1,r0,x3,x2,x1,x0,y3,y2,y1,y0)		\
+  (r0 = x0 - y0,							\
+   r1 = x1 - y1 - (r0 > x0),						\
+   r2 = x2 - y2 - (r1 > x1),						\
+   r3 = x3 - y3 - (r2 > x2))
+#endif
+
+#ifndef __FP_FRAC_DEC_3
+#define __FP_FRAC_DEC_3(x2,x1,x0,y2,y1,y0)				\
+  do {									\
+    UWtype _t0, _t1;							\
+    _t0 = x0;								\
+    x0 -= y0;								\
+    _t1 = x1;								\
+    x1 -= y1 + (x0 > _t0);						\
+    x2 -= y2 + (x1 > _t1);						\
+  } while (0)
+#endif
+
+#ifndef __FP_FRAC_DEC_4
+#define __FP_FRAC_DEC_4(x3,x2,x1,x0,y3,y2,y1,y0)			\
+  do {									\
+    UWtype _t0, _t1;							\
+    _t0 = x0;								\
+    x0 -= y0;								\
+    _t1 = x1;								\
+    x1 -= y1 + (x0 > _t0);						\
+    _t0 = x2;								\
+    x2 -= y2 + (x1 > _t1);						\
+    x3 -= y3 + (x2 > _t0);						\
+  } while (0)
+#endif
+
+#ifndef __FP_FRAC_ADDI_4
+#define __FP_FRAC_ADDI_4(x3,x2,x1,x0,i)					\
+  do {									\
+    UWtype _t;								\
+    _t = ((x0 += i) < i);						\
+    x1 += _t; _t = (x1 < _t);						\
+    x2 += _t; _t = (x2 < _t);						\
+    x3 += _t;								\
+  } while (0)
+#endif
+
+/* Convert FP values between word sizes. This appears to be more
+ * complicated than I'd have expected it to be, so these might be
+ * wrong... These macros are in any case somewhat bogus because they
+ * use information about what various FRAC_n variables look like 
+ * internally [eg, that 2 word vars are X_f0 and x_f1]. But so do
+ * the ones in op-2.h and op-1.h. 
+ */
+#define _FP_FRAC_CONV_1_4(dfs, sfs, D, S)				\
+   do {									\
+     if (S##_c != FP_CLS_NAN)						\
+       _FP_FRAC_SRS_4(S, (_FP_WFRACBITS_##sfs - _FP_WFRACBITS_##dfs),	\
+			  _FP_WFRACBITS_##sfs);				\
+     else								\
+       _FP_FRAC_SRL_4(S, (_FP_WFRACBITS_##sfs - _FP_WFRACBITS_##dfs));	\
+     D##_f = S##_f[0];							\
+  } while (0)
+
+#define _FP_FRAC_CONV_2_4(dfs, sfs, D, S)				\
+   do {									\
+     if (S##_c != FP_CLS_NAN)						\
+       _FP_FRAC_SRS_4(S, (_FP_WFRACBITS_##sfs - _FP_WFRACBITS_##dfs),	\
+		      _FP_WFRACBITS_##sfs);				\
+     else								\
+       _FP_FRAC_SRL_4(S, (_FP_WFRACBITS_##sfs - _FP_WFRACBITS_##dfs));	\
+     D##_f0 = S##_f[0];							\
+     D##_f1 = S##_f[1];							\
+  } while (0)
+
+/* Assembly/disassembly for converting to/from integral types.  
+ * No shifting or overflow handled here.
+ */
+/* Put the FP value X into r, which is an integer of size rsize. */
+#define _FP_FRAC_ASSEMBLE_4(r, X, rsize)				\
+  do {									\
+    if (rsize <= _FP_W_TYPE_SIZE)					\
+      r = X##_f[0];							\
+    else if (rsize <= 2*_FP_W_TYPE_SIZE)				\
+    {									\
+      r = X##_f[1];							\
+      r <<= _FP_W_TYPE_SIZE;						\
+      r += X##_f[0];							\
+    }									\
+    else								\
+    {									\
+      /* I'm feeling lazy so we deal with int == 3words (implausible)*/	\
+      /* and int == 4words as a single case.			 */	\
+      r = X##_f[3];							\
+      r <<= _FP_W_TYPE_SIZE;						\
+      r += X##_f[2];							\
+      r <<= _FP_W_TYPE_SIZE;						\
+      r += X##_f[1];							\
+      r <<= _FP_W_TYPE_SIZE;						\
+      r += X##_f[0];							\
+    }									\
+  } while (0)
+
+/* "No disassemble Number Five!" */
+/* move an integer of size rsize into X's fractional part. We rely on
+ * the _f[] array consisting of words of size _FP_W_TYPE_SIZE to avoid
+ * having to mask the values we store into it.
+ */
+#define _FP_FRAC_DISASSEMBLE_4(X, r, rsize)				\
+  do {									\
+    X##_f[0] = r;							\
+    X##_f[1] = (rsize <= _FP_W_TYPE_SIZE ? 0 : r >> _FP_W_TYPE_SIZE);	\
+    X##_f[2] = (rsize <= 2*_FP_W_TYPE_SIZE ? 0 : r >> 2*_FP_W_TYPE_SIZE); \
+    X##_f[3] = (rsize <= 3*_FP_W_TYPE_SIZE ? 0 : r >> 3*_FP_W_TYPE_SIZE); \
+  } while (0);
+
+#define _FP_FRAC_CONV_4_1(dfs, sfs, D, S)				\
+   do {									\
+     D##_f[0] = S##_f;							\
+     D##_f[1] = D##_f[2] = D##_f[3] = 0;				\
+     _FP_FRAC_SLL_4(D, (_FP_WFRACBITS_##dfs - _FP_WFRACBITS_##sfs));	\
+   } while (0)
+
+#define _FP_FRAC_CONV_4_2(dfs, sfs, D, S)				\
+   do {									\
+     D##_f[0] = S##_f0;							\
+     D##_f[1] = S##_f1;							\
+     D##_f[2] = D##_f[3] = 0;						\
+     _FP_FRAC_SLL_4(D, (_FP_WFRACBITS_##dfs - _FP_WFRACBITS_##sfs));	\
+   } while (0)
+