Re: [PATCH] Save and restore SSE registers in _dl_runtime_resolve.

[Jakub Jelinek <jakub at redhat dot com>]

On Tue, May 11, 2010 at 10:36:34PM +0200, Petr Baudis wrote:
> On Tue, May 11, 2010 at 10:23:45AM -0700, Richard Henderson wrote:
> > On 05/11/2010 09:26 AM, Joe Damato wrote:
> > > Hi,
> > > 
> > > It seems that _dl_runtime_resolve should be saving and restoring the
> > > SSE registers to comply with the amd64 ABI, unless I am reading it
> > > incorrectly (and I very well could be).
> > 
> > We only need to do that if the dynamic linker clobbers
> > those registers, and it should not.
> 
> Can we be sure, with modern gcc and auto-parallelization? Or are we
> taking some countermeasures against this that I'm not seeing?

tests: $(objpfx)tst-xmmymm.out
$(objpfx)tst-xmmymm.out: ../sysdeps/x86_64/tst-xmmymm.sh $(objpfx)ld.so
	@echo "Checking ld.so for SSE register use.  This will take a few seconds..."
	$(SHELL) -e $< $(objpfx) > $@

in sysdeps/x86_64/Makefile isn't it?

	Jakub