[LLVMdev] PR400 - alignment for LD/ST

[Chris Lattner]

On Thu, 29 Mar 2007, Christopher Lamb wrote:
>>  I get many distractions per day, so do not hesitate if you want to
>>  take care of PR 400 now.
>
> I'm not really sure exactly what's left to do to fully implement what I need. 
> I had assumed that this work would allow me to determine if a LD/ST was based 
> on an aligned pointer or not, but this seems now like the tip of the iceberg.
>
> I'm hoping that I can declare aligned types and retain that information when 
> I pass a pointer to one of these types to function, or declare a pointer to 
> an aligned type as a local variable. It seems that implementing this not only 
> requires the alignment attribute on loads and stores (in the LLVM bc) but 
> propagation of this information from the frontend.
>
> Is this correct?

Yes, but the front-end already has this information.  I believe that the 
only missing piece (for over-aligned data) is being able to represent that 
info on the load/store instructions.

-Chris

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