Version two of the patch including a test case.

On Mon, May 02, 2016 at 09:10:25AM -0600, Jeff Law wrote:
> On 04/29/2016 04:12 PM, Dominik Vogt wrote:
> >The attached patch removes excess stack space allocation with
> >alloca in some situations.  Plese check the commit message in the
> >patch for details.

> However, I would strongly recommend some tests, even if they are
> target specific.  You can always copy pr36728-1 into the s390x
> directory and look at size of the generated stack.  Simliarly for
> pr50938 for x86.

However, x86 uses the "else" branch in round_push, i.e. it uses
"virtual_preferred_stack_boundary_rtx" to calculate the number of
bytes to add for stack alignment.  That value is unknown at the
time round_push is called, so the test case fails on such targets,
and I've no idea how to fix this properly.

Ciao

Dominik ^_^  ^_^

-- 

Dominik Vogt
IBM Germany