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Re: [PATCH 1/1] sparc: support for -mmisalign in the SPARC M8


Hi, David,

thanks a lot for your comment.

see my reply below

> STRICT_ALIGNMENT has a lot of implications.

from the definition of STRICT_ALIGNMENT:

/* Set this nonzero if move instructions will actually fail to work
   when given unaligned data.  */
#define STRICT_ALIGNMENT 1

for MISALIGN_TARGET,  it’s clear that move instructions will NOT fail to work when given unaligned data.
so, it’s reasonable to set STRICT_ALIGNMENT to 0 for MISALIGN_TARGET.

> 
> I think just because we happen to have misaligned loads and stores
> available doesn't mean we want all of the side effects associated
> with STRICT_ALIGNMENT being true.

so, could you please specify what kind of side effects will have when =
set STRICT_ALIGNMENT to true on TARGET_MISALIGN?=20

thanks a lot.

Qing

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