On Tue, Mar 04, 2014 at 04:44:57PM +0800, lin zuojian wrote:
> On Tue, Mar 04, 2014 at 09:04:56AM +0100, Jakub Jelinek wrote:
> > On Tue, Mar 04, 2014 at 11:11:45AM +0800, lin zuojian wrote:
> > > Without aligning the asan stack base,this base will only 64-bit aligned 
> > > in ARM machines.
> > > But asan require 256-bit aligned base because of this:
> > > 1.right shift take ASAN_SHADOW_SHIFT(which is 3) bits are zeros
> > > 2.store multiple/load multiple instructions require the other 2 bits are 
> > > zeros
> > > 
> > > that add up lowest 5 bits should be zeros.That means 32 bytes or 256 bits 
> > > aligned.
> > > 
> > >     * asan.c (asan_emit_stack_protection): Force the base to align to
> > >     appropriate bits if STRICT_ALIGNMENT.  Set shadow_mem align to
> > >     appropriate bits if STRICT_ALIGNMENT.
> > >     * cfgexpand.c (expand_stack_vars): Set base_align appropriately
> > >     when asan is on.
> > >     (expand_used_vars): Leave a space in the stack frame for alignment if
> > >     STRICT_ALIGNMENT.
> > 
> > There were still a couple of formatting issues, I've fixed them below.
> > Now, do you have a GCC copyright assignment or are under copyright
> > assignment of some company working on GCC (ARM?)?
> Thanks for the fixing!.
> I have none of them.I have read the website,but don't know what exactly
> I am expecting to do.

Please follow
http://git.savannah.gnu.org/cgit/gnulib.git/plain/doc/Copyright/request-assign.future

        Jakub

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