[PowerPC] gcc.dg/torture/fp-int-convert-timode.c

[Alan Modra <amodra at bigpond dot net dot au>]

As the comment says below, some of the long double tests here fail due
to excess precision.  The problem is that gcc's real.c
ibm_extended_format (and mips_extended_format) fp constants are rounded
to 106 bit precision, whereas actual precision is variable with a
minimum of 106 bits.  (In fact, with proper rounding as done by
rs6000/darwinldouble.c, the minimum precision is 107 bits.)  So a TImode
constant assigned directly to a long double variable (and thus evaluated
by real.c) may have a different value to the same constant converted at
runtime.  Fixing real.c to properly mimic IBM Extended Double behaviour
isn't trivial, so I'd like to disable the long double tests here.  I
don't want  the whole fp-int-convert-timode.c test xfailed, because the
float and double tests ought to pass.

	* gcc.dg/torture/fp-int-convert-timode.c: Don't test IBM
	Extended Double long doubles or repeat tests when long double is
	the same size as double.

Tested powerpc64-linux.

Index: gcc/testsuite/gcc.dg/torture/fp-int-convert-timode.c
===================================================================
--- gcc/testsuite/gcc.dg/torture/fp-int-convert-timode.c	(revision 109034)
+++ gcc/testsuite/gcc.dg/torture/fp-int-convert-timode.c	(working copy)
@@ -11,6 +11,11 @@ main (void)
 {
   TEST_I_F(TItype, UTItype, float, FLT_MANT_DIG);
   TEST_I_F(TItype, UTItype, double, DBL_MANT_DIG);
+  /* Disable the long double tests when using IBM Extended Doubles.
+     They have variable precision, but constants calculated by gcc's
+     real.c assume fixed precision.  */
+#if DBL_MANT_DIG != LDBL_MANT_DIG  && LDBL_MANT_DIG != 106
   TEST_I_F(TItype, UTItype, long double, LDBL_MANT_DIG);
+#endif
   exit (0);
 }

-- 
Alan Modra
IBM OzLabs - Linux Technology Centre