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Date: Mon, 11 Apr 2022 13:47:56 +0100
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Subject: Re: Complex multiply optimization working?
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To: Richard Biener <richard.guenther@gmail.com>
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On 11/04/2022 13:02, Richard Biener wrote:
> You need to check the vectorizer dump whether a complex pattern
> was recognized or not.  Did you properly use -ffast-math?

Aha! I needed to enable -ffast-math.

I missed that this is unsafe, and there's a fall-back to _muldc3 on NaN.

OK, presumably I need to implement a vector version of the fall-back 
libcall if I want this to work without ffast-math.

Thanks

Andrew