Re: a patch for PR68695

[Jakub Jelinek <jakub@redhat.com>]

On Fri, Apr 01, 2016 at 04:26:41PM -0400, Vladimir Makarov wrote:
> >I've noticed that after this patch, 2 tests regress (PASS -> FAIL) on arm:
> >   gcc.dg/ira-shrinkwrap-prep-2.c scan-rtl-dump pro_and_epilogue
> >"Performing shrink-wrapping"
> >   gcc.dg/pr10474.c scan-rtl-dump pro_and_epilogue "Performing shrink-wrapping"
> >
> 
> I've checked the generated code.  RA with the patch generates a better code
> for the both tests. So shrink wrap optimization failed. The final code has 1
> insn less for the both tests when the patch is applied.
> 
> I guess it is wrong to write quality tests based on expected code generated
> before any optimization.  It has sense if we provide the same input.  LLVM
> testsuite is mostly such tests as they have a readable IR.  GCC
> unfortunately has no serialized and readable IR. On the other hand LLVM
> lacks integrated testing.
> 
> So I'd mark these tests as XFAIL or removed arm from DEJAGNU target in the
> tests.

FYI, those 2 tests also now FAIL on ppc64{,le}-linux in addition to
armv7hl-linux-gnueabi.

	Jakub