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Re: divide 64-bit by constant for 32-bit target machines


On 04/20/2012 01:57 PM, Dinar Temirbulatov wrote:
> Here is the patch that adds support for divide 64-bit by constant for
> 32-bit target machines, this patch was tested on arm-7a with no new
> regressions, also I am not sure on how to avoid for example i686
> targets since div operation there is fast compared to over targets and
> it showed better performance with  libc/sysdeps/wordsize-32/divdi3.c
> __udivdi3 vs my implementation on the compiler side, it is not clear
> for me by looking at the udiv_cost[speed][SImode] value.

I can't approve this patch.  However, I do think that a comment
which explains the algorithm is needed.

Andrew.


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