public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/65401] [5 Regression] make_field_assignment broken for big-endian
Date: Thu, 12 Mar 2015 13:44:00 -0000	[thread overview]
Message-ID: <bug-65401-4-E70HD3rGeJ@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-65401-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65401

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
In the
9345      else if (GET_CODE (rhs) == AND
9346           && paradoxical_subreg_p (XEXP (rhs, 0))
9347           && GET_CODE (SUBREG_REG (XEXP (rhs, 0))) == MEM
9348           && CONST_INT_P (XEXP (rhs, 1))
9349           && rtx_equal_for_field_assignment_p (gen_rtx_MEM (GET_MODE
(dest),
9350                                     XEXP (SUBREG_REG (XEXP (rhs, 0)), 0)),
9351                            dest))
hunks (two similar ones) sometimes GET_MODE (SUBREG_REG (XEXP (rhs, 0))) is
== GET_MODE (dest), then it is certainly safe for big endian and you shouldn't
need to even create a new MEM.
For the other case, I'd say when increasing the mode size you really need to
adjust the address of the mem for endianity, dunno if it is possible to have
also narrower dest than the SUBREG_REG MEM, in that case punt?
Oh, and please use MEM_P instead of GET_CODE () == MEM.


  parent reply	other threads:[~2015-03-12 13:44 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-03-12 12:25 [Bug rtl-optimization/65401] New: " jakub at gcc dot gnu.org
2015-03-12 12:25 ` [Bug rtl-optimization/65401] " jakub at gcc dot gnu.org
2015-03-12 12:39 ` jakub at gcc dot gnu.org
2015-03-12 13:36 ` law at redhat dot com
2015-03-12 13:44 ` jakub at gcc dot gnu.org [this message]
2015-03-14  8:54 ` jakub at gcc dot gnu.org
2015-03-14  8:59 ` jakub at gcc dot gnu.org

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=bug-65401-4-E70HD3rGeJ@http.gcc.gnu.org/bugzilla/ \
    --to=gcc-bugzilla@gcc.gnu.org \
    --cc=gcc-bugs@gcc.gnu.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).