llvm dev - Mar 2012 - [LLVMdev] Stack alignment on X86 AVX seems incorrect

On Thu, Mar 01, 2012 at 06:16:46PM +0000, Demikhovsky, Elena
wrote:
> vmovaps should not access stack if it is not aligned to 32
I'm not completely sure I understand your problem. Are you saying that
the generated code assumes 256bit alignment, your default stack
alignment is 128bit and LLVM doesn't adjust it automatically?

Joerg

When stack is unaligned, LLVM should generate vmovups instead of vmovaps.

- Elena

-----Original Message-----
From: llvmdev-bounces at cs.uiuc.edu [mailto:llvmdev-bounces at cs.uiuc.edu] On
Behalf Of Joerg Sonnenberger
Sent: Thursday, March 01, 2012 20:31
To: llvmdev at cs.uiuc.edu
Subject: Re: [LLVMdev] Stack alignment on X86 AVX seems incorrect

On Thu, Mar 01, 2012 at 06:16:46PM +0000, Demikhovsky, Elena
wrote:
> vmovaps should not access stack if it is not aligned to 32
I'm not completely sure I understand your problem. Are you saying that
the generated code assumes 256bit alignment, your default stack
alignment is 128bit and LLVM doesn't adjust it automatically?

Joerg
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On Thu, Mar 01, 2012 at 07:44:42PM +0000, Demikhovsky, Elena
wrote:
> When stack is unaligned, LLVM should generate vmovups instead of vmovaps.
That's the question I have asked. If LLVM believes the stack is aligned,
the choice is correct.

Joerg
> 
> - Elena
> 
> -----Original Message-----
> From: llvmdev-bounces at cs.uiuc.edu [mailto:llvmdev-bounces at
cs.uiuc.edu] On Behalf Of Joerg Sonnenberger
> Sent: Thursday, March 01, 2012 20:31
> To: llvmdev at cs.uiuc.edu
> Subject: Re: [LLVMdev] Stack alignment on X86 AVX seems incorrect
> 
> On Thu, Mar 01, 2012 at 06:16:46PM +0000, Demikhovsky, Elena wrote:
> > vmovaps should not access stack if it is not aligned to 32
> 
> I'm not completely sure I understand your problem. Are you saying that
> the generated code assumes 256bit alignment, your default stack
> alignment is 128bit and LLVM doesn't adjust it automatically?
> 
> Joerg
> _______________________________________________
> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
> ---------------------------------------------------------------------
> Intel Israel (74) Limited
> 
> This e-mail and any attachments may contain confidential material for
> the sole use of the intended recipient(s). Any review or distribution
> by others is strictly prohibited. If you are not the intended
> recipient, please contact the sender and delete all copies.
>