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Subject: Re: [vect] Re-analyze all modes for epilogues
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To: Richard Biener <rguenther@suse.de>
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From: "Andre Vieira (lists)" <andre.simoesdiasvieira@arm.com>
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On 07/12/2021 11:45, Richard Biener wrote:
> Can you check whether, give we know the main VF, the epilogue analysis
> does not start with am autodetected vector mode that needs a too large VF?

Hmm struggling to see how we could check this here. AFAIU before we 
analyze the loop for a given vector mode we won't know the VF? Are you 
saying that we could reject an autodetected mode which NUNITS > main VF 
for !LOOP_VINFO_EPIL_USING_PARTIAL_VECTORS_P? An by reject I mean we'd 
start with mode_i = 1.

Or did I misunderstand something here.

FWIW this is just to prevent extra analysis right? If the epilogue's VF 
isn't appropriate it will be rejected later.