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Re: GCC47 movmem breaks RA, GCC46 RA is fine
On 27/04/12 09:21, Richard Guenther wrote:
This differs from what GCC47 does and seems to work better.
I would like help on how to best handle this situation under GCC47.
Not provide movmem which looks like open-coded and not in any way
Thanks Richard, however I don't understand your comment.
GCC46 outputs for this problem:
and GCC47, once movmemqi and setmemqi are disabled:
It feels to me that GCC46 version is better:
* no branch to subroutine memcpy;
* less stack usage (argument to enterl);
So, using our block copy (bc2) instruction is an optimisation, don't you