optimization/8049: SSE unaligned vector stores crash with -O0

[Ian Ollmann]

The following reply was made to PR optimization/8049; it has been noted by GNATS.

From: Ian Ollmann <iano@cco.caltech.edu>
To: Jan Hubicka <jh@suse.cz>
Cc: hubicka@gcc.gnu.org, <gcc-bugs@gcc.gnu.org>, <gcc-prs@gcc.gnu.org>,
        <gcc-gnats@gcc.gnu.org>
Subject: Re: optimization/8049: SSE unaligned vector stores crash with -O0
Date: Thu, 10 Oct 2002 10:54:51 -0700

 On Thu, 10 Oct 2002, Jan Hubicka wrote:
 
 > > On 10 Oct 2002 hubicka@gcc.gnu.org wrote:
 > >
 > > > Synopsis: SSE unaligned vector stores crash with -O0
 > > >
 > > > State-Changed-From-To: open->closed
 > > > State-Changed-By: hubicka
 > > > State-Changed-When: Thu Oct 10 09:45:59 2002
 > > > State-Changed-Why:
 > > >     It is runtime bug to not align stack properly for main.
 > > >     It will go away with runtime compiled using gcc 3.2 or can be workarounded by avoiding vector stuff in main.
 > > >
 > > > http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=8049
 > >
 > > I see this in functions that are not main(). Didn't I provide an example
 > > of one?
 >
 > I didn't see it.  Can you send me some?
 
 The original example is one.  The three buffers passed into MatrixMultiply
 happen to be aligned on my system. The actual crash happens when the stack
 copy of C1 is loaded, before the _mm_store_ps (uninlined) function is
 called.
 
 Ian
 
 ---------------------------------------------------
    Ian Ollmann, Ph.D.       iano@cco.caltech.edu
 ---------------------------------------------------