2.5-18.1

1 files changed, 816 insertions, 295 deletions

diff --git a/soft-fp/op-common.h b/soft-fp/op-common.h
index 3abafa1..0aa6e3e 100644
--- a/soft-fp/op-common.h
+++ b/soft-fp/op-common.h
@@ -1,5 +1,5 @@
 /* Software floating-point emulation. Common operations.
-   Copyright (C) 1997,1998,1999 Free Software Foundation, Inc.
+   Copyright (C) 1997,1998,1999,2006,2007 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),
@@ -11,6 +11,15 @@
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.
 
+   In addition to the permissions in the GNU Lesser General Public
+   License, the Free Software Foundation gives you unlimited
+   permission to link the compiled version of this file into
+   combinations with other programs, and to distribute those
+   combinations without any restriction coming from the use of this
+   file.  (The Lesser General Public License restrictions do apply in
+   other respects; for example, they cover modification of the file,
+   and distribution when not linked into a combine executable.)
+
    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
@@ -18,11 +27,11 @@
 
    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.  */
+   Software Foundation, 51 Franklin Street, Fifth Floor, Boston,
+   MA 02110-1301, USA.  */
 
-#define _FP_DECL(wc, X)			\
-  _FP_I_TYPE X##_c, X##_s, X##_e;	\
+#define _FP_DECL(wc, X)						\
+  _FP_I_TYPE X##_c __attribute__((unused)), X##_s, X##_e;	\
   _FP_FRAC_DECL_##wc(X)
 
 /*
@@ -71,6 +80,87 @@ do {									\
   }									\
 } while (0)
 
+/* Finish unpacking an fp value in semi-raw mode: the mantissa is
+   shifted by _FP_WORKBITS but the implicit MSB is not inserted and
+   other classification is not done.  */
+#define _FP_UNPACK_SEMIRAW(fs, wc, X)	_FP_FRAC_SLL_##wc(X, _FP_WORKBITS)
+
+/* A semi-raw value has overflowed to infinity.  Adjust the mantissa
+   and exponent appropriately.  */
+#define _FP_OVERFLOW_SEMIRAW(fs, wc, X)			\
+do {							\
+  if (FP_ROUNDMODE == FP_RND_NEAREST			\
+      || (FP_ROUNDMODE == FP_RND_PINF && !X##_s)	\
+      || (FP_ROUNDMODE == FP_RND_MINF && X##_s))	\
+    {							\
+      X##_e = _FP_EXPMAX_##fs;				\
+      _FP_FRAC_SET_##wc(X, _FP_ZEROFRAC_##wc);		\
+    }							\
+  else							\
+    {							\
+      X##_e = _FP_EXPMAX_##fs - 1;			\
+      _FP_FRAC_SET_##wc(X, _FP_MAXFRAC_##wc);		\
+    }							\
+    FP_SET_EXCEPTION(FP_EX_INEXACT);			\
+    FP_SET_EXCEPTION(FP_EX_OVERFLOW);			\
+} while (0)
+
+/* Check for a semi-raw value being a signaling NaN and raise the
+   invalid exception if so.  */
+#define _FP_CHECK_SIGNAN_SEMIRAW(fs, wc, X)			\
+do {								\
+  if (X##_e == _FP_EXPMAX_##fs					\
+      && !_FP_FRAC_ZEROP_##wc(X)				\
+      && !(_FP_FRAC_HIGH_##fs(X) & _FP_QNANBIT_SH_##fs))	\
+    FP_SET_EXCEPTION(FP_EX_INVALID);				\
+} while (0)
+
+/* Choose a NaN result from an operation on two semi-raw NaN
+   values.  */
+#define _FP_CHOOSENAN_SEMIRAW(fs, wc, R, X, Y, OP)			\
+do {									\
+  /* _FP_CHOOSENAN expects raw values, so shift as required.  */	\
+  _FP_FRAC_SRL_##wc(X, _FP_WORKBITS);					\
+  _FP_FRAC_SRL_##wc(Y, _FP_WORKBITS);					\
+  _FP_CHOOSENAN(fs, wc, R, X, Y, OP);					\
+  _FP_FRAC_SLL_##wc(R, _FP_WORKBITS);					\
+} while (0)
+
+/* Test whether a biased exponent is normal (not zero or maximum).  */
+#define _FP_EXP_NORMAL(fs, wc, X)	(((X##_e + 1) & _FP_EXPMAX_##fs) > 1)
+
+/* Prepare to pack an fp value in semi-raw mode: the mantissa is
+   rounded and shifted right, with the rounding possibly increasing
+   the exponent (including changing a finite value to infinity).  */
+#define _FP_PACK_SEMIRAW(fs, wc, X)				\
+do {								\
+  _FP_ROUND(wc, X);						\
+  if (_FP_FRAC_HIGH_##fs(X)					\
+      & (_FP_OVERFLOW_##fs >> 1))				\
+    {								\
+      _FP_FRAC_HIGH_##fs(X) &= ~(_FP_OVERFLOW_##fs >> 1);	\
+      X##_e++;							\
+      if (X##_e == _FP_EXPMAX_##fs)				\
+	_FP_OVERFLOW_SEMIRAW(fs, wc, X);			\
+    }								\
+  _FP_FRAC_SRL_##wc(X, _FP_WORKBITS);				\
+  if (!_FP_EXP_NORMAL(fs, wc, X) && !_FP_FRAC_ZEROP_##wc(X))	\
+    {								\
+      if (X##_e == 0)						\
+	FP_SET_EXCEPTION(FP_EX_UNDERFLOW);			\
+      else							\
+	{							\
+	  if (!_FP_KEEPNANFRACP)				\
+	    {							\
+	      _FP_FRAC_SET_##wc(X, _FP_NANFRAC_##fs);		\
+	      X##_s = _FP_NANSIGN_##fs;				\
+	    }							\
+	  else							\
+	    _FP_FRAC_HIGH_RAW_##fs(X) |= _FP_QNANBIT_##fs;	\
+	}							\
+    }								\
+} while (0)
+
 /*
  * Before packing the bits back into the native fp result, take care
  * of such mundane things as rounding and overflow.  Also, for some
@@ -202,153 +292,433 @@ do {								\
 
 
 
-/*
- * Main addition routine.  The input values should be cooked.
- */
-
-#define _FP_ADD_INTERNAL(fs, wc, R, X, Y, OP)				     \
-do {									     \
-  switch (_FP_CLS_COMBINE(X##_c, Y##_c))				     \
-  {									     \
-  case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_NORMAL):			     \
-    {									     \
-      /* shift the smaller number so that its exponent matches the larger */ \
-      _FP_I_TYPE diff = X##_e - Y##_e;					     \
-									     \
-      if (diff < 0)							     \
-	{								     \
-	  diff = -diff;							     \
-	  if (diff <= _FP_WFRACBITS_##fs)				     \
-	    _FP_FRAC_SRS_##wc(X, diff, _FP_WFRACBITS_##fs);		     \
-	  else if (!_FP_FRAC_ZEROP_##wc(X))				     \
-	    _FP_FRAC_SET_##wc(X, _FP_MINFRAC_##wc);			     \
-	  R##_e = Y##_e;						     \
-	}								     \
-      else								     \
-	{								     \
-	  if (diff > 0)							     \
-	    {								     \
-	      if (diff <= _FP_WFRACBITS_##fs)				     \
-	        _FP_FRAC_SRS_##wc(Y, diff, _FP_WFRACBITS_##fs);		     \
-	      else if (!_FP_FRAC_ZEROP_##wc(Y))				     \
-	        _FP_FRAC_SET_##wc(Y, _FP_MINFRAC_##wc);			     \
-	    }								     \
-	  R##_e = X##_e;						     \
-	}								     \
-									     \
-      R##_c = FP_CLS_NORMAL;						     \
-									     \
-      if (X##_s == Y##_s)						     \
-	{								     \
-	  R##_s = X##_s;						     \
-	  _FP_FRAC_ADD_##wc(R, X, Y);					     \
-	  if (_FP_FRAC_OVERP_##wc(fs, R))				     \
-	    {								     \
-	      _FP_FRAC_SRS_##wc(R, 1, _FP_WFRACBITS_##fs);		     \
-	      R##_e++;							     \
-	    }								     \
-	}								     \
-      else								     \
-	{								     \
-	  R##_s = X##_s;						     \
-	  _FP_FRAC_SUB_##wc(R, X, Y);					     \
-	  if (_FP_FRAC_ZEROP_##wc(R))					     \
-	    {								     \
-	      /* return an exact zero */				     \
-	      if (FP_ROUNDMODE == FP_RND_MINF)				     \
-		R##_s |= Y##_s;						     \
-	      else							     \
-		R##_s &= Y##_s;						     \
-	      R##_c = FP_CLS_ZERO;					     \
-	    }								     \
-	  else								     \
-	    {								     \
-	      if (_FP_FRAC_NEGP_##wc(R))				     \
-		{							     \
-		  _FP_FRAC_SUB_##wc(R, Y, X);				     \
-		  R##_s = Y##_s;					     \
-		}							     \
-									     \
-	      /* renormalize after subtraction */			     \
-	      _FP_FRAC_CLZ_##wc(diff, R);				     \
-	      diff -= _FP_WFRACXBITS_##fs;				     \
-	      if (diff)							     \
-		{							     \
-		  R##_e -= diff;					     \
-		  _FP_FRAC_SLL_##wc(R, diff);				     \
-		}							     \
-	    }								     \
-	}								     \
-      break;								     \
-    }									     \
-									     \
-  case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_NAN):				     \
-    _FP_CHOOSENAN(fs, wc, R, X, Y, OP);					     \
-    break;								     \
-									     \
-  case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_ZERO):			     \
-    R##_e = X##_e;							     \
-  case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_NORMAL):			     \
-  case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_INF):				     \
-  case _FP_CLS_COMBINE(FP_CLS_NAN,FP_CLS_ZERO):				     \
-    _FP_FRAC_COPY_##wc(R, X);						     \
-    R##_s = X##_s;							     \
-    R##_c = X##_c;							     \
-    break;								     \
-									     \
-  case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_NORMAL):			     \
-    R##_e = Y##_e;							     \
-  case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_NAN):			     \
-  case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_NAN):				     \
-  case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_NAN):				     \
-    _FP_FRAC_COPY_##wc(R, Y);						     \
-    R##_s = Y##_s;							     \
-    R##_c = Y##_c;							     \
-    break;								     \
-									     \
-  case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_INF):				     \
-    if (X##_s != Y##_s)							     \
-      {									     \
-	/* +INF + -INF => NAN */					     \
-	_FP_FRAC_SET_##wc(R, _FP_NANFRAC_##fs);				     \
-	R##_s = _FP_NANSIGN_##fs;					     \
-	R##_c = FP_CLS_NAN;						     \
-	FP_SET_EXCEPTION(FP_EX_INVALID);				     \
-	break;								     \
-      }									     \
-    /* FALLTHRU */							     \
-									     \
-  case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_NORMAL):			     \
-  case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_ZERO):				     \
-    R##_s = X##_s;							     \
-    R##_c = FP_CLS_INF;							     \
-    break;								     \
-									     \
-  case _FP_CLS_COMBINE(FP_CLS_NORMAL,FP_CLS_INF):			     \
-  case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_INF):				     \
-    R##_s = Y##_s;							     \
-    R##_c = FP_CLS_INF;							     \
-    break;								     \
-									     \
-  case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_ZERO):			     \
-    /* make sure the sign is correct */					     \
-    if (FP_ROUNDMODE == FP_RND_MINF)					     \
-      R##_s = X##_s | Y##_s;						     \
-    else								     \
-      R##_s = X##_s & Y##_s;						     \
-    R##_c = FP_CLS_ZERO;						     \
-    break;								     \
-									     \
-  default:								     \
-    abort();								     \
-  }									     \
+/* Addition on semi-raw values.  */
+#define _FP_ADD_INTERNAL(fs, wc, R, X, Y, OP)				 \
+do {									 \
+  if (X##_s == Y##_s)							 \
+    {									 \
+      /* Addition.  */							 \
+      R##_s = X##_s;							 \
+      int ediff = X##_e - Y##_e;					 \
+      if (ediff > 0)							 \
+	{								 \
+	  R##_e = X##_e;						 \
+	  if (Y##_e == 0)						 \
+	    {								 \
+	      /* Y is zero or denormalized.  */				 \
+	      if (_FP_FRAC_ZEROP_##wc(Y))				 \
+		{							 \
+		  _FP_CHECK_SIGNAN_SEMIRAW(fs, wc, X);			 \
+		  _FP_FRAC_COPY_##wc(R, X);				 \
+		  goto add_done;					 \
+		}							 \
+	      else							 \
+		{							 \
+		  FP_SET_EXCEPTION(FP_EX_DENORM);			 \
+		  ediff--;						 \
+		  if (ediff == 0)					 \
+		    {							 \
+		      _FP_FRAC_ADD_##wc(R, X, Y);			 \
+		      goto add3;					 \
+		    }							 \
+		  if (X##_e == _FP_EXPMAX_##fs)				 \
+		    {							 \
+		      _FP_CHECK_SIGNAN_SEMIRAW(fs, wc, X);		 \
+		      _FP_FRAC_COPY_##wc(R, X);				 \
+		      goto add_done;					 \
+		    }							 \
+		  goto add1;						 \
+		}							 \
+	    }								 \
+	  else if (X##_e == _FP_EXPMAX_##fs)				 \
+	    {								 \
+	      /* X is NaN or Inf, Y is normal.  */			 \
+	      _FP_CHECK_SIGNAN_SEMIRAW(fs, wc, X);			 \
+	      _FP_FRAC_COPY_##wc(R, X);					 \
+	      goto add_done;						 \
+	    }								 \
+									 \
+	  /* Insert implicit MSB of Y.  */				 \
+	  _FP_FRAC_HIGH_##fs(Y) |= _FP_IMPLBIT_SH_##fs;			 \
+									 \
+	add1:								 \
+	  /* Shift the mantissa of Y to the right EDIFF steps;		 \
+	     remember to account later for the implicit MSB of X.  */	 \
+	  if (ediff <= _FP_WFRACBITS_##fs)				 \
+	    _FP_FRAC_SRS_##wc(Y, ediff, _FP_WFRACBITS_##fs);		 \
+	  else if (!_FP_FRAC_ZEROP_##wc(Y))				 \
+	    _FP_FRAC_SET_##wc(Y, _FP_MINFRAC_##wc);			 \
+	  _FP_FRAC_ADD_##wc(R, X, Y);					 \
+	}								 \
+      else if (ediff < 0)						 \
+	{								 \
+	  ediff = -ediff;						 \
+	  R##_e = Y##_e;						 \
+	  if (X##_e == 0)						 \
+	    {								 \
+	      /* X is zero or denormalized.  */				 \
+	      if (_FP_FRAC_ZEROP_##wc(X))				 \
+		{							 \
+		  _FP_CHECK_SIGNAN_SEMIRAW(fs, wc, Y);			 \
+		  _FP_FRAC_COPY_##wc(R, Y);				 \
+		  goto add_done;					 \
+		}							 \
+	      else							 \
+		{							 \
+		  FP_SET_EXCEPTION(FP_EX_DENORM);			 \
+		  ediff--;						 \
+		  if (ediff == 0)					 \
+		    {							 \
+		      _FP_FRAC_ADD_##wc(R, Y, X);			 \
+		      goto add3;					 \
+		    }							 \
+		  if (Y##_e == _FP_EXPMAX_##fs)				 \
+		    {							 \
+		      _FP_CHECK_SIGNAN_SEMIRAW(fs, wc, Y);		 \
+		      _FP_FRAC_COPY_##wc(R, Y);				 \
+		      goto add_done;					 \
+		    }							 \
+		  goto add2;						 \
+		}							 \
+	    }								 \
+	  else if (Y##_e == _FP_EXPMAX_##fs)				 \
+	    {								 \
+	      /* Y is NaN or Inf, X is normal.  */			 \
+	      _FP_CHECK_SIGNAN_SEMIRAW(fs, wc, Y);			 \
+	      _FP_FRAC_COPY_##wc(R, Y);					 \
+	      goto add_done;						 \
+	    }								 \
+									 \
+	  /* Insert implicit MSB of X.  */				 \
+	  _FP_FRAC_HIGH_##fs(X) |= _FP_IMPLBIT_SH_##fs;			 \
+									 \
+	add2:								 \
+	  /* Shift the mantissa of X to the right EDIFF steps;		 \
+	     remember to account later for the implicit MSB of Y.  */	 \
+	  if (ediff <= _FP_WFRACBITS_##fs)				 \
+	    _FP_FRAC_SRS_##wc(X, ediff, _FP_WFRACBITS_##fs);		 \
+	  else if (!_FP_FRAC_ZEROP_##wc(X))				 \
+	    _FP_FRAC_SET_##wc(X, _FP_MINFRAC_##wc);			 \
+	  _FP_FRAC_ADD_##wc(R, Y, X);					 \
+	}								 \
+      else								 \
+	{								 \
+	  /* ediff == 0.  */						 \
+	  if (!_FP_EXP_NORMAL(fs, wc, X))				 \
+	    {								 \
+	      if (X##_e == 0)						 \
+		{							 \
+		  /* X and Y are zero or denormalized.  */		 \
+		  R##_e = 0;						 \
+		  if (_FP_FRAC_ZEROP_##wc(X))				 \
+		    {							 \
+		      if (!_FP_FRAC_ZEROP_##wc(Y))			 \
+			FP_SET_EXCEPTION(FP_EX_DENORM);			 \
+		      _FP_FRAC_COPY_##wc(R, Y);				 \
+		      goto add_done;					 \
+		    }							 \
+		  else if (_FP_FRAC_ZEROP_##wc(Y))			 \
+		    {							 \
+		      FP_SET_EXCEPTION(FP_EX_DENORM);			 \
+		      _FP_FRAC_COPY_##wc(R, X);				 \
+		      goto add_done;					 \
+		    }							 \
+		  else							 \
+		    {							 \
+		      FP_SET_EXCEPTION(FP_EX_DENORM);			 \
+		      _FP_FRAC_ADD_##wc(R, X, Y);			 \
+		      if (_FP_FRAC_HIGH_##fs(R) & _FP_IMPLBIT_SH_##fs)	 \
+			{						 \
+			  /* Normalized result.  */			 \
+			  _FP_FRAC_HIGH_##fs(R)				 \
+			    &= ~(_FP_W_TYPE)_FP_IMPLBIT_SH_##fs;	 \
+			  R##_e = 1;					 \
+			}						 \
+		      goto add_done;					 \
+		    }							 \
+		}							 \
+	      else							 \
+		{							 \
+		  /* X and Y are NaN or Inf.  */			 \
+		  _FP_CHECK_SIGNAN_SEMIRAW(fs, wc, X);			 \
+		  _FP_CHECK_SIGNAN_SEMIRAW(fs, wc, Y);			 \
+		  R##_e = _FP_EXPMAX_##fs;				 \
+		  if (_FP_FRAC_ZEROP_##wc(X))				 \
+		    _FP_FRAC_COPY_##wc(R, Y);				 \
+		  else if (_FP_FRAC_ZEROP_##wc(Y))			 \
+		    _FP_FRAC_COPY_##wc(R, X);				 \
+		  else							 \
+		    _FP_CHOOSENAN_SEMIRAW(fs, wc, R, X, Y, OP);		 \
+		  goto add_done;					 \
+		}							 \
+	    }								 \
+	  /* The exponents of X and Y, both normal, are equal.  The	 \
+	     implicit MSBs will always add to increase the		 \
+	     exponent.  */						 \
+	  _FP_FRAC_ADD_##wc(R, X, Y);					 \
+	  R##_e = X##_e + 1;						 \
+	  _FP_FRAC_SRS_##wc(R, 1, _FP_WFRACBITS_##fs);			 \
+	  if (R##_e == _FP_EXPMAX_##fs)					 \
+	    /* Overflow to infinity (depending on rounding mode).  */	 \
+	    _FP_OVERFLOW_SEMIRAW(fs, wc, R);				 \
+	  goto add_done;						 \
+	}								 \
+    add3:								 \
+      if (_FP_FRAC_HIGH_##fs(R) & _FP_IMPLBIT_SH_##fs)			 \
+	{								 \
+	  /* Overflow.  */						 \
+	  _FP_FRAC_HIGH_##fs(R) &= ~(_FP_W_TYPE)_FP_IMPLBIT_SH_##fs;	 \
+	  R##_e++;							 \
+	  _FP_FRAC_SRS_##wc(R, 1, _FP_WFRACBITS_##fs);			 \
+	  if (R##_e == _FP_EXPMAX_##fs)					 \
+	    /* Overflow to infinity (depending on rounding mode).  */	 \
+	    _FP_OVERFLOW_SEMIRAW(fs, wc, R);				 \
+	}								 \
+    add_done: ;								 \
+    }									 \
+  else									 \
+    {									 \
+      /* Subtraction.  */						 \
+      int ediff = X##_e - Y##_e;					 \
+      if (ediff > 0)							 \
+	{								 \
+	  R##_e = X##_e;						 \
+	  R##_s = X##_s;						 \
+	  if (Y##_e == 0)						 \
+	    {								 \
+	      /* Y is zero or denormalized.  */				 \
+	      if (_FP_FRAC_ZEROP_##wc(Y))				 \
+		{							 \
+		  _FP_CHECK_SIGNAN_SEMIRAW(fs, wc, X);			 \
+		  _FP_FRAC_COPY_##wc(R, X);				 \
+		  goto sub_done;					 \
+		}							 \
+	      else							 \
+		{							 \
+		  FP_SET_EXCEPTION(FP_EX_DENORM);			 \
+		  ediff--;						 \
+		  if (ediff == 0)					 \
+		    {							 \
+		      _FP_FRAC_SUB_##wc(R, X, Y);			 \
+		      goto sub3;					 \
+		    }							 \
+		  if (X##_e == _FP_EXPMAX_##fs)				 \
+		    {							 \
+		      _FP_CHECK_SIGNAN_SEMIRAW(fs, wc, X);		 \
+		      _FP_FRAC_COPY_##wc(R, X);				 \
+		      goto sub_done;					 \
+		    }							 \
+		  goto sub1;						 \
+		}							 \
+	    }								 \
+	  else if (X##_e == _FP_EXPMAX_##fs)				 \
+	    {								 \
+	      /* X is NaN or Inf, Y is normal.  */			 \
+	      _FP_CHECK_SIGNAN_SEMIRAW(fs, wc, X);			 \
+	      _FP_FRAC_COPY_##wc(R, X);					 \
+	      goto sub_done;						 \
+	    }								 \
+									 \
+	  /* Insert implicit MSB of Y.  */				 \
+	  _FP_FRAC_HIGH_##fs(Y) |= _FP_IMPLBIT_SH_##fs;			 \
+									 \
+	sub1:								 \
+	  /* Shift the mantissa of Y to the right EDIFF steps;		 \
+	     remember to account later for the implicit MSB of X.  */	 \
+	  if (ediff <= _FP_WFRACBITS_##fs)				 \
+	    _FP_FRAC_SRS_##wc(Y, ediff, _FP_WFRACBITS_##fs);		 \
+	  else if (!_FP_FRAC_ZEROP_##wc(Y))				 \
+	    _FP_FRAC_SET_##wc(Y, _FP_MINFRAC_##wc);			 \
+	  _FP_FRAC_SUB_##wc(R, X, Y);					 \
+	}								 \
+      else if (ediff < 0)						 \
+	{								 \
+	  ediff = -ediff;						 \
+	  R##_e = Y##_e;						 \
+	  R##_s = Y##_s;						 \
+	  if (X##_e == 0)						 \
+	    {								 \
+	      /* X is zero or denormalized.  */				 \
+	      if (_FP_FRAC_ZEROP_##wc(X))				 \
+		{							 \
+		  _FP_CHECK_SIGNAN_SEMIRAW(fs, wc, Y);			 \
+		  _FP_FRAC_COPY_##wc(R, Y);				 \
+		  goto sub_done;					 \
+		}							 \
+	      else							 \
+		{							 \
+		  FP_SET_EXCEPTION(FP_EX_DENORM);			 \
+		  ediff--;						 \
+		  if (ediff == 0)					 \
+		    {							 \
+		      _FP_FRAC_SUB_##wc(R, Y, X);			 \
+		      goto sub3;					 \
+		    }							 \
+		  if (Y##_e == _FP_EXPMAX_##fs)				 \
+		    {							 \
+		      _FP_CHECK_SIGNAN_SEMIRAW(fs, wc, Y);		 \
+		      _FP_FRAC_COPY_##wc(R, Y);				 \
+		      goto sub_done;					 \
+		    }							 \
+		  goto sub2;						 \
+		}							 \
+	    }								 \
+	  else if (Y##_e == _FP_EXPMAX_##fs)				 \
+	    {								 \
+	      /* Y is NaN or Inf, X is normal.  */			 \
+	      _FP_CHECK_SIGNAN_SEMIRAW(fs, wc, Y);			 \
+	      _FP_FRAC_COPY_##wc(R, Y);					 \
+	      goto sub_done;						 \
+	    }								 \
+									 \
+	  /* Insert implicit MSB of X.  */				 \
+	  _FP_FRAC_HIGH_##fs(X) |= _FP_IMPLBIT_SH_##fs;			 \
+									 \
+	sub2:								 \
+	  /* Shift the mantissa of X to the right EDIFF steps;		 \
+	     remember to account later for the implicit MSB of Y.  */	 \
+	  if (ediff <= _FP_WFRACBITS_##fs)				 \
+	    _FP_FRAC_SRS_##wc(X, ediff, _FP_WFRACBITS_##fs);		 \
+	  else if (!_FP_FRAC_ZEROP_##wc(X))				 \
+	    _FP_FRAC_SET_##wc(X, _FP_MINFRAC_##wc);			 \
+	  _FP_FRAC_SUB_##wc(R, Y, X);					 \
+	}								 \
+      else								 \
+	{								 \
+	  /* ediff == 0.  */						 \
+	  if (!_FP_EXP_NORMAL(fs, wc, X))				 \
+	    {								 \
+	      if (X##_e == 0)						 \
+		{							 \
+		  /* X and Y are zero or denormalized.  */		 \
+		  R##_e = 0;						 \
+		  if (_FP_FRAC_ZEROP_##wc(X))				 \
+		    {							 \
+		      _FP_FRAC_COPY_##wc(R, Y);				 \
+		      if (_FP_FRAC_ZEROP_##wc(Y))			 \
+			R##_s = (FP_ROUNDMODE == FP_RND_MINF);		 \
+		      else						 \
+			{						 \
+			  FP_SET_EXCEPTION(FP_EX_DENORM);		 \
+			  R##_s = Y##_s;				 \
+			}						 \
+		      goto sub_done;					 \
+		    }							 \
+		  else if (_FP_FRAC_ZEROP_##wc(Y))			 \
+		    {							 \
+		      FP_SET_EXCEPTION(FP_EX_DENORM);			 \
+		      _FP_FRAC_COPY_##wc(R, X);				 \
+		      R##_s = X##_s;					 \
+		      goto sub_done;					 \
+		    }							 \
+		  else							 \
+		    {							 \
+		      FP_SET_EXCEPTION(FP_EX_DENORM);			 \
+		      _FP_FRAC_SUB_##wc(R, X, Y);			 \
+		      R##_s = X##_s;					 \
+		      if (_FP_FRAC_HIGH_##fs(R) & _FP_IMPLBIT_SH_##fs)	 \
+			{						 \
+			  /* |X| < |Y|, negate result.  */		 \
+			  _FP_FRAC_SUB_##wc(R, Y, X);			 \
+			  R##_s = Y##_s;				 \
+			}						 \
+		      else if (_FP_FRAC_ZEROP_##wc(R))			 \
+			R##_s = (FP_ROUNDMODE == FP_RND_MINF);		 \
+		      goto sub_done;					 \
+		    }							 \
+		}							 \
+	      else							 \
+		{							 \
+		  /* X and Y are NaN or Inf, of opposite signs.  */	 \
+		  _FP_CHECK_SIGNAN_SEMIRAW(fs, wc, X);			 \
+		  _FP_CHECK_SIGNAN_SEMIRAW(fs, wc, Y);			 \
+		  R##_e = _FP_EXPMAX_##fs;				 \
+		  if (_FP_FRAC_ZEROP_##wc(X))				 \
+		    {							 \
+		      if (_FP_FRAC_ZEROP_##wc(Y))			 \
+			{						 \
+			  /* Inf - Inf.  */				 \
+			  R##_s = _FP_NANSIGN_##fs;			 \
+			  _FP_FRAC_SET_##wc(R, _FP_NANFRAC_##fs);	 \
+			  _FP_FRAC_SLL_##wc(R, _FP_WORKBITS);		 \
+			  FP_SET_EXCEPTION(FP_EX_INVALID);		 \
+			}						 \
+		      else						 \
+			{						 \
+			  /* Inf - NaN.  */				 \
+			  R##_s = Y##_s;				 \
+			  _FP_FRAC_COPY_##wc(R, Y);			 \
+			}						 \
+		    }							 \
+		  else							 \
+		    {							 \
+		      if (_FP_FRAC_ZEROP_##wc(Y))			 \
+			{						 \
+			  /* NaN - Inf.  */				 \
+			  R##_s = X##_s;				 \
+			  _FP_FRAC_COPY_##wc(R, X);			 \
+			}						 \
+		      else						 \
+			{						 \
+			  /* NaN - NaN.  */				 \
+			  _FP_CHOOSENAN_SEMIRAW(fs, wc, R, X, Y, OP);	 \
+			}						 \
+		    }							 \
+		  goto sub_done;					 \
+		}							 \
+	    }								 \
+	  /* The exponents of X and Y, both normal, are equal.  The	 \
+	     implicit MSBs cancel.  */					 \
+	  R##_e = X##_e;						 \
+	  _FP_FRAC_SUB_##wc(R, X, Y);					 \
+	  R##_s = X##_s;						 \
+	  if (_FP_FRAC_HIGH_##fs(R) & _FP_IMPLBIT_SH_##fs)		 \
+	    {								 \
+	      /* |X| < |Y|, negate result.  */				 \
+	      _FP_FRAC_SUB_##wc(R, Y, X);				 \
+	      R##_s = Y##_s;						 \
+	    }								 \
+	  else if (_FP_FRAC_ZEROP_##wc(R))				 \
+	    {								 \
+	      R##_e = 0;						 \
+	      R##_s = (FP_ROUNDMODE == FP_RND_MINF);			 \
+	      goto sub_done;						 \
+	    }								 \
+	  goto norm;							 \
+	}								 \
+    sub3:								 \
+      if (_FP_FRAC_HIGH_##fs(R) & _FP_IMPLBIT_SH_##fs)			 \
+	{								 \
+	  int diff;							 \
+	  /* Carry into most significant bit of larger one of X and Y,	 \
+	     canceling it; renormalize.  */				 \
+	  _FP_FRAC_HIGH_##fs(R) &= _FP_IMPLBIT_SH_##fs - 1;		 \
+	norm:								 \
+	  _FP_FRAC_CLZ_##wc(diff, R);					 \
+	  diff -= _FP_WFRACXBITS_##fs;					 \
+	  _FP_FRAC_SLL_##wc(R, diff);					 \
+	  if (R##_e <= diff)						 \
+	    {								 \
+	      /* R is denormalized.  */					 \
+	      diff = diff - R##_e + 1;					 \
+	      _FP_FRAC_SRS_##wc(R, diff, _FP_WFRACBITS_##fs);		 \
+	      R##_e = 0;						 \
+	    }								 \
+	  else								 \
+	    {								 \
+	      R##_e -= diff;						 \
+	      _FP_FRAC_HIGH_##fs(R) &= ~(_FP_W_TYPE)_FP_IMPLBIT_SH_##fs; \
+	    }								 \
+	}								 \
+    sub_done: ;								 \
+    }									 \
 } while (0)
 
 #define _FP_ADD(fs, wc, R, X, Y) _FP_ADD_INTERNAL(fs, wc, R, X, Y, '+')
-#define _FP_SUB(fs, wc, R, X, Y)					     \
-  do {									     \
-    if (Y##_c != FP_CLS_NAN) Y##_s ^= 1;				     \
-    _FP_ADD_INTERNAL(fs, wc, R, X, Y, '-');				     \
+#define _FP_SUB(fs, wc, R, X, Y)					    \
+  do {									    \
+    if (!(Y##_e == _FP_EXPMAX_##fs && !_FP_FRAC_ZEROP_##wc(Y))) Y##_s ^= 1; \
+    _FP_ADD_INTERNAL(fs, wc, R, X, Y, '-');				    \
   } while (0)
 
 
@@ -537,20 +907,28 @@ do {							\
 
 /* Simplification for strict equality.  */
 
-#define _FP_CMP_EQ(fs, wc, ret, X, Y)					  \
-  do {									  \
-    /* NANs are unordered */						  \
-    if ((X##_e == _FP_EXPMAX_##fs && !_FP_FRAC_ZEROP_##wc(X))		  \
-	|| (Y##_e == _FP_EXPMAX_##fs && !_FP_FRAC_ZEROP_##wc(Y)))	  \
-      {									  \
-	ret = 1;							  \
-      }									  \
-    else								  \
-      {									  \
-	ret = !(X##_e == Y##_e						  \
-		&& _FP_FRAC_EQ_##wc(X, Y)				  \
-		&& (X##_s == Y##_s || !X##_e && _FP_FRAC_ZEROP_##wc(X))); \
-      }									  \
+#define _FP_CMP_EQ(fs, wc, ret, X, Y)					    \
+  do {									    \
+    /* NANs are unordered */						    \
+    if ((X##_e == _FP_EXPMAX_##fs && !_FP_FRAC_ZEROP_##wc(X))		    \
+	|| (Y##_e == _FP_EXPMAX_##fs && !_FP_FRAC_ZEROP_##wc(Y)))	    \
+      {									    \
+	ret = 1;							    \
+      }									    \
+    else								    \
+      {									    \
+	ret = !(X##_e == Y##_e						    \
+		&& _FP_FRAC_EQ_##wc(X, Y)				    \
+		&& (X##_s == Y##_s || (!X##_e && _FP_FRAC_ZEROP_##wc(X)))); \
+      }									    \
+  } while (0)
+
+/* Version to test unordered.  */
+
+#define _FP_CMP_UNORD(fs, wc, ret, X, Y)				\
+  do {									\
+    ret = ((X##_e == _FP_EXPMAX_##fs && !_FP_FRAC_ZEROP_##wc(X))	\
+	   || (Y##_e == _FP_EXPMAX_##fs && !_FP_FRAC_ZEROP_##wc(Y)));	\
   } while (0)
 
 /*
@@ -608,115 +986,280 @@ do {									\
   } while (0)
 
 /*
- * Convert from FP to integer
+ * Convert from FP to integer.  Input is raw.
  */
 
 /* RSIGNED can have following values:
  * 0:  the number is required to be 0..(2^rsize)-1, if not, NV is set plus
- *     the result is either 0 or (2^rsize)-1 depending on the sign in such case.
- * 1:  the number is required to be -(2^(rsize-1))..(2^(rsize-1))-1, if not, NV is
- *     set plus the result is either -(2^(rsize-1)) or (2^(rsize-1))-1 depending
- *     on the sign in such case.
+ *     the result is either 0 or (2^rsize)-1 depending on the sign in such
+ *     case.
+ * 1:  the number is required to be -(2^(rsize-1))..(2^(rsize-1))-1, if not,
+ *     NV is set plus the result is either -(2^(rsize-1)) or (2^(rsize-1))-1
+ *     depending on the sign in such case.
  * -1: the number is required to be -(2^(rsize-1))..(2^rsize)-1, if not, NV is
- *     set plus the result is either -(2^(rsize-1)) or (2^(rsize-1))-1 depending
- *     on the sign in such case.
+ *     set plus the result is either -(2^(rsize-1)) or (2^(rsize-1))-1
+ *     depending on the sign in such case.
  */
-#define _FP_TO_INT(fs, wc, r, X, rsize, rsigned)				\
-  do {										\
-    switch (X##_c)								\
-      {										\
-      case FP_CLS_NORMAL:							\
-	if (X##_e < 0)								\
-	  {									\
-	    FP_SET_EXCEPTION(FP_EX_INEXACT);					\
-	  case FP_CLS_ZERO:							\
-	    r = 0;								\
-	  }									\
-	else if (X##_e >= rsize - (rsigned > 0 || X##_s)			\
-		 || (!rsigned && X##_s))					\
-	  {	/* overflow */							\
-	  case FP_CLS_NAN:                                                      \
-	  case FP_CLS_INF:							\
-	    if (rsigned)							\
-	      {									\
-		r = 1;								\
-		r <<= rsize - 1;						\
-		r -= 1 - X##_s;							\
-	      } else {								\
-		r = 0;								\
-		if (X##_s)							\
-		  r = ~r;							\
-	      }									\
-	    FP_SET_EXCEPTION(FP_EX_INVALID);					\
-	  }									\
-	else									\
-	  {									\
-	    if (_FP_W_TYPE_SIZE*wc < rsize)					\
-	      {									\
-		_FP_FRAC_ASSEMBLE_##wc(r, X, rsize);				\
-		r <<= X##_e - _FP_WFRACBITS_##fs;				\
-	      }									\
-	    else								\
-	      {									\
-		if (X##_e >= _FP_WFRACBITS_##fs)				\
-		  _FP_FRAC_SLL_##wc(X, (X##_e - _FP_WFRACBITS_##fs + 1));	\
-		else if (X##_e < _FP_WFRACBITS_##fs - 1)			\
-		  {								\
-		    _FP_FRAC_SRS_##wc(X, (_FP_WFRACBITS_##fs - X##_e - 2),	\
-				      _FP_WFRACBITS_##fs);			\
-		    if (_FP_FRAC_LOW_##wc(X) & 1)				\
-		      FP_SET_EXCEPTION(FP_EX_INEXACT);				\
-		    _FP_FRAC_SRL_##wc(X, 1);					\
-		  }								\
-		_FP_FRAC_ASSEMBLE_##wc(r, X, rsize);				\
-	      }									\
-	    if (rsigned && X##_s)						\
-	      r = -r;								\
-	  }									\
-	break;									\
-      }										\
-  } while (0)
-
-#define _FP_FROM_INT(fs, wc, X, r, rsize, rtype)			\
-  do {									\
-    if (r)								\
-      {									\
-        unsigned rtype ur_;						\
-	X##_c = FP_CLS_NORMAL;						\
-									\
-	if ((X##_s = (r < 0)))						\
-	  r = -r;							\
-									\
-	ur_ = (unsigned rtype) r;					\
-	if (rsize <= _FP_W_TYPE_SIZE)					\
-	  __FP_CLZ(X##_e, ur_);						\
-	else								\
-	  __FP_CLZ_2(X##_e, (_FP_W_TYPE)(ur_ >> _FP_W_TYPE_SIZE), 	\
-		     (_FP_W_TYPE)ur_);					\
-	if (rsize < _FP_W_TYPE_SIZE)					\
-		X##_e -= (_FP_W_TYPE_SIZE - rsize);			\
-	X##_e = rsize - X##_e - 1;					\
+#define _FP_TO_INT(fs, wc, r, X, rsize, rsigned)			\
+do {									\
+  if (X##_e < _FP_EXPBIAS_##fs)						\
+    {									\
+      r = 0;								\
+      if (X##_e == 0)							\
+	{								\
+	  if (!_FP_FRAC_ZEROP_##wc(X))					\
+	    {								\
+	      FP_SET_EXCEPTION(FP_EX_INEXACT);				\
+	      FP_SET_EXCEPTION(FP_EX_DENORM);				\
+	    }								\
+	}								\
+      else								\
+	FP_SET_EXCEPTION(FP_EX_INEXACT);				\
+    }									\
+  else if (X##_e >= _FP_EXPBIAS_##fs + rsize - (rsigned > 0 || X##_s)	\
+	   || (!rsigned && X##_s))					\
+    {									\
+      /* Overflow or converting to the most negative integer.  */	\
+      if (rsigned)							\
+	{								\
+	  r = 1;							\
+	  r <<= rsize - 1;						\
+	  r -= 1 - X##_s;						\
+	} else {							\
+	  r = 0;							\
+	  if (X##_s)							\
+	    r = ~r;							\
+	}								\
 									\
-	if (_FP_FRACBITS_##fs < rsize && _FP_WFRACBITS_##fs < X##_e)	\
-	  __FP_FRAC_SRS_1(ur_, (X##_e - _FP_WFRACBITS_##fs + 1), rsize);\
-	_FP_FRAC_DISASSEMBLE_##wc(X, ur_, rsize);			\
-	if ((_FP_WFRACBITS_##fs - X##_e - 1) > 0)			\
-	  _FP_FRAC_SLL_##wc(X, (_FP_WFRACBITS_##fs - X##_e - 1));	\
-      }									\
-    else								\
-      {									\
-	X##_c = FP_CLS_ZERO, X##_s = 0;					\
-      }									\
+      if (rsigned && X##_s && X##_e == _FP_EXPBIAS_##fs + rsize - 1)	\
+	{								\
+	  /* Possibly converting to most negative integer; check the	\
+	     mantissa.  */						\
+	  int inexact = 0;						\
+	  (void)((_FP_FRACBITS_##fs > rsize)				\
+		 ? ({ _FP_FRAC_SRST_##wc(X, inexact,			\
+					 _FP_FRACBITS_##fs - rsize,	\
+					 _FP_FRACBITS_##fs); 0; })	\
+		 : 0);							\
+	  if (!_FP_FRAC_ZEROP_##wc(X))					\
+	    FP_SET_EXCEPTION(FP_EX_INVALID);				\
+	  else if (inexact)						\
+	    FP_SET_EXCEPTION(FP_EX_INEXACT);				\
+	}								\
+      else								\
+	FP_SET_EXCEPTION(FP_EX_INVALID);				\
+    }									\
+  else									\
+    {									\
+      _FP_FRAC_HIGH_RAW_##fs(X) |= _FP_IMPLBIT_##fs;			\
+      if (X##_e >= _FP_EXPBIAS_##fs + _FP_FRACBITS_##fs - 1)		\
+	{								\
+	  _FP_FRAC_ASSEMBLE_##wc(r, X, rsize);				\
+	  r <<= X##_e - _FP_EXPBIAS_##fs - _FP_FRACBITS_##fs + 1;	\
+	}								\
+      else								\
+	{								\
+	  int inexact;							\
+	  _FP_FRAC_SRST_##wc(X, inexact,				\
+			    (_FP_FRACBITS_##fs + _FP_EXPBIAS_##fs - 1	\
+			     - X##_e),					\
+			    _FP_FRACBITS_##fs);				\
+	  if (inexact)							\
+	    FP_SET_EXCEPTION(FP_EX_INEXACT);				\
+	  _FP_FRAC_ASSEMBLE_##wc(r, X, rsize);				\
+	}								\
+      if (rsigned && X##_s)						\
+	r = -r;								\
+    }									\
+} while (0)
+
+/* Convert integer to fp.  Output is raw.  RTYPE is unsigned even if
+   input is signed.  */
+#define _FP_FROM_INT(fs, wc, X, r, rsize, rtype)			     \
+  do {									     \
+    if (r)								     \
+      {									     \
+	rtype ur_;							     \
+									     \
+	if ((X##_s = (r < 0)))						     \
+	  r = -(rtype)r;						     \
+									     \
+	ur_ = (rtype) r;						     \
+	(void)((rsize <= _FP_W_TYPE_SIZE)				     \
+	       ? ({							     \
+		    int lz_;						     \
+		    __FP_CLZ(lz_, (_FP_W_TYPE)ur_);			     \
+		    X##_e = _FP_EXPBIAS_##fs + _FP_W_TYPE_SIZE - 1 - lz_;    \
+		  })							     \
+	       : ((rsize <= 2 * _FP_W_TYPE_SIZE)			     \
+		  ? ({							     \
+		       int lz_;						     \
+		       __FP_CLZ_2(lz_, (_FP_W_TYPE)(ur_ >> _FP_W_TYPE_SIZE), \
+				  (_FP_W_TYPE)ur_);			     \
+		       X##_e = (_FP_EXPBIAS_##fs + 2 * _FP_W_TYPE_SIZE - 1   \
+				- lz_);					     \
+		     })							     \
+		  : (abort(), 0)));					     \
+									     \
+	if (rsize - 1 + _FP_EXPBIAS_##fs >= _FP_EXPMAX_##fs		     \
+	    && X##_e >= _FP_EXPMAX_##fs)				     \
+	  {								     \
+	    /* Exponent too big; overflow to infinity.  (May also	     \
+	       happen after rounding below.)  */			     \
+	    _FP_OVERFLOW_SEMIRAW(fs, wc, X);				     \
+	    goto pack_semiraw;						     \
+	  }								     \
+									     \
+	if (rsize <= _FP_FRACBITS_##fs					     \
+	    || X##_e < _FP_EXPBIAS_##fs + _FP_FRACBITS_##fs)		     \
+	  {								     \
+	    /* Exactly representable; shift left.  */			     \
+	    _FP_FRAC_DISASSEMBLE_##wc(X, ur_, rsize);			     \
+	    _FP_FRAC_SLL_##wc(X, (_FP_EXPBIAS_##fs			     \
+				  + _FP_FRACBITS_##fs - 1 - X##_e));	     \
+	  }								     \
+	else								     \
+	  {								     \
+	    /* More bits in integer than in floating type; need to	     \
+	       round.  */						     \
+	    if (_FP_EXPBIAS_##fs + _FP_WFRACBITS_##fs - 1 < X##_e)	     \
+	      ur_ = ((ur_ >> (X##_e - _FP_EXPBIAS_##fs			     \
+			      - _FP_WFRACBITS_##fs + 1))		     \
+		     | ((ur_ << (rsize - (X##_e - _FP_EXPBIAS_##fs	     \
+					  - _FP_WFRACBITS_##fs + 1)))	     \
+			!= 0));						     \
+	    _FP_FRAC_DISASSEMBLE_##wc(X, ur_, rsize);			     \
+	    if ((_FP_EXPBIAS_##fs + _FP_WFRACBITS_##fs - 1 - X##_e) > 0)     \
+	      _FP_FRAC_SLL_##wc(X, (_FP_EXPBIAS_##fs			     \
+				    + _FP_WFRACBITS_##fs - 1 - X##_e));	     \
+	    _FP_FRAC_HIGH_##fs(X) &= ~(_FP_W_TYPE)_FP_IMPLBIT_SH_##fs;	     \
+	  pack_semiraw:							     \
+	    _FP_PACK_SEMIRAW(fs, wc, X);				     \
+	  }								     \
+      }									     \
+    else								     \
+      {									     \
+	X##_s = 0;							     \
+	X##_e = 0;							     \
+	_FP_FRAC_SET_##wc(X, _FP_ZEROFRAC_##wc);			     \
+      }									     \
   } while (0)
 
 
-#define FP_CONV(dfs,sfs,dwc,swc,D,S)			\
-  do {							\
-    _FP_FRAC_CONV_##dwc##_##swc(dfs, sfs, D, S);	\
-    D##_e = S##_e;					\
-    D##_c = S##_c;					\
-    D##_s = S##_s;					\
-  } while (0)
+/* Extend from a narrower floating-point format to a wider one.  Input
+   and output are raw.  */
+#define FP_EXTEND(dfs,sfs,dwc,swc,D,S)					 \
+do {									 \
+  if (_FP_FRACBITS_##dfs < _FP_FRACBITS_##sfs				 \
+      || (_FP_EXPMAX_##dfs - _FP_EXPBIAS_##dfs				 \
+	  < _FP_EXPMAX_##sfs - _FP_EXPBIAS_##sfs)			 \
+      || _FP_EXPBIAS_##dfs < _FP_EXPBIAS_##sfs + _FP_FRACBITS_##sfs - 1) \
+    abort();								 \
+  D##_s = S##_s;							 \
+  _FP_FRAC_COPY_##dwc##_##swc(D, S);					 \
+  if (_FP_EXP_NORMAL(sfs, swc, S))					 \
+    {									 \
+      D##_e = S##_e + _FP_EXPBIAS_##dfs - _FP_EXPBIAS_##sfs;		 \
+      _FP_FRAC_SLL_##dwc(D, (_FP_FRACBITS_##dfs - _FP_FRACBITS_##sfs));	 \
+    }									 \
+  else									 \
+    {									 \
+      if (S##_e == 0)							 \
+	{								 \
+	  if (_FP_FRAC_ZEROP_##swc(S))					 \
+	    D##_e = 0;							 \
+	  else								 \
+	    {								 \
+	      int _lz;							 \
+	      FP_SET_EXCEPTION(FP_EX_DENORM);				 \
+	      _FP_FRAC_CLZ_##swc(_lz, S);				 \
+	      _FP_FRAC_SLL_##dwc(D,					 \
+				 _lz + _FP_FRACBITS_##dfs		 \
+				 - _FP_FRACTBITS_##sfs);		 \
+	      D##_e = (_FP_EXPBIAS_##dfs - _FP_EXPBIAS_##sfs + 1	 \
+		       + _FP_FRACXBITS_##sfs - _lz);			 \
+	    }								 \
+	}								 \
+      else								 \
+	{								 \
+	  D##_e = _FP_EXPMAX_##dfs;					 \
+	  if (!_FP_FRAC_ZEROP_##swc(S))					 \
+	    {								 \
+	      if (!(_FP_FRAC_HIGH_RAW_##sfs(S) & _FP_QNANBIT_##sfs))	 \
+		FP_SET_EXCEPTION(FP_EX_INVALID);			 \
+	      _FP_FRAC_SLL_##dwc(D, (_FP_FRACBITS_##dfs			 \
+				     - _FP_FRACBITS_##sfs));		 \
+	    }								 \
+	}								 \
+    }									 \
+} while (0)
+
+/* Truncate from a wider floating-point format to a narrower one.
+   Input and output are semi-raw.  */
+#define FP_TRUNC(dfs,sfs,dwc,swc,D,S)					     \
+do {									     \
+  if (_FP_FRACBITS_##sfs < _FP_FRACBITS_##dfs				     \
+      || _FP_EXPBIAS_##sfs < _FP_EXPBIAS_##dfs + _FP_FRACBITS_##dfs - 1)     \
+    abort();								     \
+  D##_s = S##_s;							     \
+  if (_FP_EXP_NORMAL(sfs, swc, S))					     \
+    {									     \
+      D##_e = S##_e + _FP_EXPBIAS_##dfs - _FP_EXPBIAS_##sfs;		     \
+      if (D##_e >= _FP_EXPMAX_##dfs)					     \
+	_FP_OVERFLOW_SEMIRAW(dfs, dwc, D);				     \
+      else								     \
+	{								     \
+	  if (D##_e <= 0)						     \
+	    {								     \
+	      if (D##_e <= 1 - _FP_FRACBITS_##dfs)			     \
+		_FP_FRAC_SET_##swc(S, _FP_ZEROFRAC_##swc);		     \
+	      else							     \
+		{							     \
+		  _FP_FRAC_HIGH_##sfs(S) |= _FP_IMPLBIT_SH_##sfs;	     \
+		  _FP_FRAC_SRS_##swc(S, (_FP_WFRACBITS_##sfs		     \
+					 - _FP_WFRACBITS_##dfs + 1 - D##_e), \
+				     _FP_WFRACBITS_##sfs);		     \
+		}							     \
+	      D##_e = 0;						     \
+	    }								     \
+	  else								     \
+	    _FP_FRAC_SRS_##swc(S, (_FP_WFRACBITS_##sfs			     \
+				   - _FP_WFRACBITS_##dfs),		     \
+			       _FP_WFRACBITS_##sfs);			     \
+	  _FP_FRAC_COPY_##dwc##_##swc(D, S);				     \
+	}								     \
+    }									     \
+  else									     \
+    {									     \
+      if (S##_e == 0)							     \
+	{								     \
+	  D##_e = 0;							     \
+	  _FP_FRAC_SET_##dwc(D, _FP_ZEROFRAC_##dwc);			     \
+	  if (!_FP_FRAC_ZEROP_##swc(S))					     \
+	    {								     \
+	      FP_SET_EXCEPTION(FP_EX_DENORM);				     \
+	      FP_SET_EXCEPTION(FP_EX_INEXACT);				     \
+	    }								     \
+	}								     \
+      else								     \
+	{								     \
+	  D##_e = _FP_EXPMAX_##dfs;					     \
+	  if (_FP_FRAC_ZEROP_##swc(S))					     \
+	    _FP_FRAC_SET_##dwc(D, _FP_ZEROFRAC_##dwc);			     \
+	  else								     \
+	    {								     \
+	      _FP_CHECK_SIGNAN_SEMIRAW(sfs, swc, S);			     \
+	      _FP_FRAC_SRL_##swc(S, (_FP_WFRACBITS_##sfs		     \
+				     - _FP_WFRACBITS_##dfs));		     \
+	      _FP_FRAC_COPY_##dwc##_##swc(D, S);			     \
+	      /* Semi-raw NaN must have all workbits cleared.  */	     \
+	      _FP_FRAC_LOW_##dwc(D)					     \
+		&= ~(_FP_W_TYPE) ((1 << _FP_WORKBITS) - 1);		     \
+	      _FP_FRAC_HIGH_##dfs(D) |= _FP_QNANBIT_SH_##dfs;		     \
+	    }								     \
+	}								     \
+    }									     \
+} while (0)
 
 /*
  * Helper primitives.
@@ -725,40 +1268,18 @@ do {									\
 /* Count leading zeros in a word.  */
 
 #ifndef __FP_CLZ
-#if _FP_W_TYPE_SIZE < 64
-/* this is just to shut the compiler up about shifts > word length -- PMM 02/1998 */
-#define __FP_CLZ(r, x)				\
-  do {						\
-    _FP_W_TYPE _t = (x);			\
-    r = _FP_W_TYPE_SIZE - 1;			\
-    if (_t > 0xffff) r -= 16;			\
-    if (_t > 0xffff) _t >>= 16;			\
-    if (_t > 0xff) r -= 8;			\
-    if (_t > 0xff) _t >>= 8;			\
-    if (_t & 0xf0) r -= 4;			\
-    if (_t & 0xf0) _t >>= 4;			\
-    if (_t & 0xc) r -= 2;			\
-    if (_t & 0xc) _t >>= 2;			\
-    if (_t & 0x2) r -= 1;			\
-  } while (0)
-#else /* not _FP_W_TYPE_SIZE < 64 */
-#define __FP_CLZ(r, x)				\
-  do {						\
-    _FP_W_TYPE _t = (x);			\
-    r = _FP_W_TYPE_SIZE - 1;			\
-    if (_t > 0xffffffff) r -= 32;		\
-    if (_t > 0xffffffff) _t >>= 32;		\
-    if (_t > 0xffff) r -= 16;			\
-    if (_t > 0xffff) _t >>= 16;			\
-    if (_t > 0xff) r -= 8;			\
-    if (_t > 0xff) _t >>= 8;			\
-    if (_t & 0xf0) r -= 4;			\
-    if (_t & 0xf0) _t >>= 4;			\
-    if (_t & 0xc) r -= 2;			\
-    if (_t & 0xc) _t >>= 2;			\
-    if (_t & 0x2) r -= 1;			\
+/* GCC 3.4 and later provide the builtins for us.  */
+#define __FP_CLZ(r, x)							      \
+  do {									      \
+    if (sizeof (_FP_W_TYPE) == sizeof (unsigned int))			      \
+      r = __builtin_clz (x);						      \
+    else if (sizeof (_FP_W_TYPE) == sizeof (unsigned long))		      \
+      r = __builtin_clzl (x);						      \
+    else if (sizeof (_FP_W_TYPE) == sizeof (unsigned long long))	      \
+      r = __builtin_clzll (x);						      \
+    else								      \
+      abort ();								      \
   } while (0)
-#endif /* not _FP_W_TYPE_SIZE < 64 */
 #endif /* ndef __FP_CLZ */
 
 #define _FP_DIV_HELP_imm(q, r, n, d)		\