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Re: Will backend ever see an memory operand with address wrap around?

From: "H.J. Lu" <hjl dot tools at gmail dot com>
To: amylaar at spamcop dot net
Cc: Richard Guenther <richard dot guenther at gmail dot com>, GCC Development <gcc at gcc dot gnu dot org>
Date: Sun, 13 May 2012 19:07:29 -0700
Subject: Re: Will backend ever see an memory operand with address wrap around?
References: <CAMe9rOpTN5ZeLfiRvcmqRMqt=qJZ83AfO9KEZVas+u_sNs6Wdw@mail.gmail.com> <CAFiYyc1oqMCiUkNZfqM2-bVXWiL4X0-E2fHhsxKHJ+i8Qpvsqg@mail.gmail.com> <CAMe9rOpqojRF9MLKvJrJ+LTE4mJsvsMNyDrBpq9zNhFC7WXnbg@mail.gmail.com> <20120513211739.ybfq9v06yow84sok-nzlynne@webmail.spamcop.net>

On Sun, May 13, 2012 at 6:17 PM,  <amylaar@spamcop.net> wrote:
> Quoting "H.J. Lu" <hjl.tools@gmail.com>:
>
>> What is the expect run-time behavior when a + b has
>> overflow/underflow?
>
>
> The expectation is wrap-around. ?Note that loop strenght reduction can
> cause assumed wrap-around semantics in RTL for strictly conforming C input
> where no such wrap-around is in evidence.

I noticed that also.  But my impression is loop strength reduction doesn't
use wrap-around address for load/store directly.

-- 
H.J.

Follow-Ups:
- Re: Will backend ever see an memory operand with address wrap around?
  - From: Joern Rennecke

References:
- Will backend ever see an memory operand with address wrap around?
  - From: H.J. Lu
- Re: Will backend ever see an memory operand with address wrap around?
  - From: Richard Guenther
- Re: Will backend ever see an memory operand with address wrap around?
  - From: H.J. Lu
- Re: Will backend ever see an memory operand with address wrap around?
  - From: amylaar

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