Re: [Qemu-devel] Another MIPS quiet NaN fix

[Daniel Jacobowitz <drow@false.org>]

On Mon, Sep 24, 2007 at 04:05:45PM +0200, Andreas Schwab wrote:
> Daniel Jacobowitz <drow@false.org> writes:
> 
> > Glibc's test-float failed on my qemu testing.  I tracked it down to
> > these routines: if you count the bits carefully, you'll see that
> > 0x7FC00000 sets the quiet NaN bit (on most hardware - signalling NaN
> > in the MIPS case); so does a.high >> 41, which copies it from the
> > original NaN.  I think this routine should not force a quiet or
> > signalling NaN, but just preserve the input NaN's signalling-ness.
> 
> You may need to make sure that at least one mantissa bit is set.

I think - but am not quite sure - that this will already be the case
because the NaN will have come from some other NaN representation.
Good point, though - we can easily set the next bit, as long as we
don't fiddle with the signalling bit.

-- 
Daniel Jacobowitz
CodeSourcery