include:

2007-11-07  Joseph Myers  <joseph@codesourcery.com>
	    Daniel Jacobowitz  <dan@codesourcery.com>

	* floatformat.h (struct floatformat): Add split_half field.
	(floatformat_ibm_long_double): New.

libiberty:
2007-11-07  Joseph Myers  <joseph@codesourcery.com>
	    Daniel Jacobowitz  <dan@codesourcery.com>

	* floatformat.c (mant_bits_set): New.
	(floatformat_to_double): Use it.  Note no special handling of
	split formats.
	(floatformat_from_double): Note no special handing of split
	formats.
	(floatformat_ibm_long_double_is_valid,
	floatformat_ibm_long_double): New.
	(floatformat_ieee_single_big, floatformat_ieee_single_little,
	floatformat_ieee_double_big, floatformat_ieee_double_little,
	floatformat_ieee_double_littlebyte_bigword, floatformat_vax_f,
	floatformat_vax_d, floatformat_vax_g, floatformat_i387_ext,
	floatformat_m68881_ext, floatformat_i960_ext,
	floatformat_m88110_ext, floatformat_m88110_harris_ext,
	floatformat_arm_ext_big, floatformat_arm_ext_littlebyte_bigword,
	floatformat_ia64_spill_big, floatformat_ia64_spill_little,
	floatformat_ia64_quad_big, floatformat_ia64_quad_little): Update
	for addition of split_half field.

gdb:
2007-11-07  Joseph Myers  <joseph@codesourcery.com>
	    Daniel Jacobowitz  <dan@codesourcery.com>

	* gdbtypes.c (floatformats_ibm_long_double): New.
	* gdbtypes.h (floatformats_ibm_long_double): Declare.
	* ia64-tdep.c (floatformat_ia64_ext): Update for addition of
	split_half field.
	* mips-tdep.c (n32n64_floatformat_always_valid,
	floatformat_n32n64_long_double_big, floatformats_n32n64_long):
	Remove.
	(mips_gdbarch_init): Use floatformats_ibm_long_double instead of
	floatformats_n32n64_long.
	* ppc-linux-tdep.c (ppc_linux_init_abi): Use 128-bit IBM long
	double.
	* doublest.c (convert_floatformat_to_doublest,
	convert_doublest_to_floatformat): Handle split floating-point
	formats.
	* ppc-sysv-tdep.c (ppc_sysv_abi_push_dummy_call): Handle IBM long
	double arguments.
	(ppc64_sysv_abi_push_dummy_call): Likewise.
	(do_ppc_sysv_return_value): Handle IBM long double return.

1 files changed, 42 insertions, 0 deletions

diff --git a/gdb/doublest.c b/gdb/doublest.c
index c7ca993..3ec6dd3 100644
--- a/gdb/doublest.c
+++ b/gdb/doublest.c
@@ -200,6 +200,24 @@ convert_floatformat_to_doublest (const struct floatformat *fmt,
   if (order != fmt->byteorder)
     ufrom = newfrom;
 
+  if (fmt->split_half)
+    {
+      double dtop, dbot;
+      floatformat_to_double (fmt->split_half, ufrom, &dtop);
+      /* Preserve the sign of 0, which is the sign of the top
+	 half.  */
+      if (dtop == 0.0)
+	{
+	  *to = (DOUBLEST) dtop;
+	  return;
+	}
+      floatformat_to_double (fmt->split_half,
+			     ufrom + fmt->totalsize / FLOATFORMAT_CHAR_BIT / 2,
+			     &dbot);
+      *to = (DOUBLEST) dtop + (DOUBLEST) dbot;
+      return;
+    }
+
   exponent = get_field (ufrom, order, fmt->totalsize, fmt->exp_start,
 			fmt->exp_len);
   /* Note that if exponent indicates a NaN, we can't really do anything useful
@@ -392,6 +410,30 @@ convert_doublest_to_floatformat (CONST struct floatformat *fmt,
   memcpy (&dfrom, from, sizeof (dfrom));
   memset (uto, 0, (fmt->totalsize + FLOATFORMAT_CHAR_BIT - 1) 
                     / FLOATFORMAT_CHAR_BIT);
+
+  if (fmt->split_half)
+    {
+      /* Use static volatile to ensure that any excess precision is
+	 removed via storing in memory, and so the top half really is
+	 the result of converting to double.  */
+      static volatile double dtop, dbot;
+      double dtopnv, dbotnv;
+      dtop = (double) dfrom;
+      /* If the rounded top half is Inf, the bottom must be 0 not NaN
+	 or Inf.  */
+      if (dtop + dtop == dtop && dtop != 0.0)
+	dbot = 0.0;
+      else
+	dbot = (double) (dfrom - (DOUBLEST) dtop);
+      dtopnv = dtop;
+      dbotnv = dbot;
+      floatformat_from_double (fmt->split_half, &dtopnv, uto);
+      floatformat_from_double (fmt->split_half, &dbotnv,
+			       (uto
+				+ fmt->totalsize / FLOATFORMAT_CHAR_BIT / 2));
+      return;
+    }
+
   if (dfrom == 0)
     return;			/* Result is zero */
   if (dfrom != dfrom)		/* Result is NaN */