[PATCH][RFC] Fix PR39943, wrong code with vectorized conversion on x86_64

[Richard Guenther]

On Wed, 29 Apr 2009, Janis Johnson wrote:

> On Wed, 2009-04-29 at 10:40 +0200, Richard Guenther wrote:
> > On Tue, 28 Apr 2009, Uros Bizjak wrote:
> > 
> > > Richard Guenther wrote:
> > > > This fixes the ICE on 177.mesa caused by type checking which catched
> > > > the wrong-code issue that we are happily doing vectorized
> > > > float -> unsigned and unsigned -> float conversions with the SSE
> > > > cvtdq2ps and cvttps2dq instructions which only work with signed
> > > > integer value ranges.  Oops.
> > > > 
> > > > ...
> > > > 
> > > > because they all use conversions to/from unsigned ints.  Ira - do you
> > > > prefer adding another vector capability, vect_uintfloat_cvt, here
> > > > or placing strategic XFAILs in the tests?  Are there corresponding
> > > > tests for signed int conversions?  Do ppc and ia64 really handle this
> > > > cases correctly?
> > > > 
> > > > I'll bootstrap / test this soon.  Uros, is the backend change ok?
> > > >   
> > > 
> > > Yes, backend change is OK for all branches.
> > 
> > This implements the testsuite harness extensions.  Janis, are the
> > testsuite changes ok for trunk (if re-testing succeeds)?
> > 
> > Thanks,
> > Richard.
> > 
> > 2009-04-28  Richard Guenther  <rguenther@suse.de>
> > 
> > 	PR target/39943
> > 	* config/i386/i386.c (ix86_vectorize_builtin_conversion): Only
> > 	allow conversion to signed integers.
> > 
> > 	* lib/target-supports.exp (check_effective_target_vect_uintfloat_cvt):
> > 	New.
> > 	(check_effective_target_vect_floatuint_cvt): Likewise.
> > 	* gcc.dg/vect/slp-10.c: Adjust.
> > 	* gcc.dg/vect/slp-11.c: Adjust.
> > 	* gcc.dg/vect/slp-12b.c: Adjust.
> > 	* gcc.dg/vect/slp-33.c: Adjust.
> > 	* gcc.c-torture/compile/pr39943.c: New testcase.
> 
> I'm not familiar with powerpc-*-linux*paired*; is that functionality
> ever available in a compiler with a different target triplet?  If not,
> this is OK, otherwise you'll need a check that covers the functionality
> rather than the triplet.

I have no idea.  I just copied from the existing
check_effective_target_vect_intfloat_cvt check which this patch
splits into a signed and an unsigned variant.

Richard.