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Date: Mon, 13 Jan 2014 17:24:00 -0000
Message-ID: <CAGSvup9qUfTfYOm6FyUcDFeKp4dJtFMjWaC+XnjT6Ca+OqYguA@mail.gmail.com>
Subject: Re: [PATCH] Add zero-overhead looping for xtensa backend
From: Sterling Augustine <augustine.sterling@gmail.com>
To: "Yangfei (Felix)" <felix.yang@huawei.com>
Cc: Felix Yang <fei.yang0953@gmail.com>, 	"gcc-patches@gcc.gnu.org" <gcc-patches@gcc.gnu.org>
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On Thu, Jan 9, 2014 at 7:48 PM, Yangfei (Felix) <felix.yang@huawei.com> wrote:
> And here is the xtensa configuration tested (include/xtensa-config.h):
>
> #define XCHAL_HAVE_BE           0
> #define XCHAL_HAVE_LOOPS                1


Hi Felix,

I like this patch, and expect I will approve it. However, I would like
you to do two more things before I do:

1. Ensure it doesn't generate zcl's when:

#define XCHAL_HAVE_LOOPS 0

2. Ensure it doesn't produce loops bodies that contain ret, retw,
ret.n or retw.n as the last instruction. It might be easier to just
disallow them in loop bodies entirely though.

Thanks!