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Re: Fix middle-end/17767


On Tue, Jan 04, 2005 at 10:18:50AM +0100, Uros Bizjak wrote:
> This patch fixes PR target/17767 (middle-end/17767). fold_rtx () should 
> handle vector modes, when two equal vectors are compared.

Should, yes, but this doesn't do it.

> The solution is to compose a false_rtx and true_rtx from 
> VECTOR_STORE_FLAG_VALUE and return this vector as a result for vector 
> modes, instead of only scalar const_false_rtx/const_true_rtx.

No, a *proper* solution is to perform the comparison element-by-element
as the real vector compare instruction does.  Producing only 0 or 
only 0xffff_ffff_ffff_ffff is no good.

I think you should just always skip vector compares for 4.0.


r~


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