[committed] SH: Regenerate libm-test-ulps

[Joseph S. Myers]

On Mon, 27 Jan 2014, kkojima@rr.iij4u.or.jp wrote:

> Hi,
> 
> It turned out that I've produced a bogus ulps without -mieee SH gcc
> option which is required for proper IEEE arithmetic on this target.
> I've committed the updated libm-test-ulps with enabling -mieee.

If -mieee is needed for IEEE arithmetic, then sysdeps/sh/sh4/Makefile 
needs to do

sysdep-CFLAGS += -mieee

or similar, much like ports/sysdeps/alpha/Makefile does.  It shouldn't 
rely on the user passing special options when building glibc, glibc should 
use the right options automatically.

(But I notice

  /* If the -mieee option was not explicitly set by the user, turn it on
     unless -ffinite-math-only was specified.  See also PR 33135.  */
  if (! global_options_set.x_TARGET_IEEE)
    TARGET_IEEE = ! flag_finite_math_only;

in GCC, suggesting this should be the default - is it not working for some 
reason?)

> Although it looks that the issues for fma went away, there are
> new fma_towardzero lines.  I'll update Bug 16503 with that result.
> I'd like to look into those *_towardzero cases.

Those all seem to involve subnormals, so I suspect some problem with those 
somewhere.

Incidentally, I notice that SH4 has an fmac instruction (single-precision 
only) - if it is indeed a fused operation, it might make sense to use it 
to implement fmaf for sh/sh4/fpu (once the other problems are fixed - this 
is of course just an optimization).

-- 
Joseph S. Myers
joseph@codesourcery.com