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Re: Proposal for path splitting for reduction in register pressure for Loops.
- From: Richard Biener <richard dot guenther at gmail dot com>
- To: Jeff Law <law at redhat dot com>
- Cc: Ajit Kumar Agarwal <ajit dot kumar dot agarwal at xilinx dot com>, "vmakarov at redhat dot com" <vmakarov at redhat dot com>, "gcc at gcc dot gnu dot org" <gcc at gcc dot gnu dot org>, Vinod Kathail <vinodk at xilinx dot com>, Shail Aditya Gupta <shailadi at xilinx dot com>, Vidhumouli Hunsigida <vidhum at xilinx dot com>, Nagaraju Mekala <nmekala at xilinx dot com>
- Date: Mon, 9 Mar 2015 12:40:49 +0100
- Subject: Re: Proposal for path splitting for reduction in register pressure for Loops.
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On Sun, Mar 8, 2015 at 8:49 PM, Jeff Law <firstname.lastname@example.org> wrote:
> On 03/08/15 12:13, Richard Biener wrote:
>> I see. This basically creates two loop latches and thus will make our
>> loop detection code turn the loop into a fake loop nest. Not sure if that
>> is a good idea.
> I'd have to sit down and ponder this for a while -- what would be the
> register pressure implications of duplicating the contents of the join block
> into its predecessors, leaving an empty joiner so that we still have a
> single latch?
Good question. Now another question is why we don't choose this
way to disambiguate loops with multiple latches? (create a forwarder
as new single latch block)