public inbox for gcc@gcc.gnu.org
 help / color / mirror / Atom feed
From: Richard Henderson <rth@redhat.com>
To: John David Anglin <dave@hiauly1.hia.nrc.ca>
Cc: gcc@gcc.gnu.org
Subject: Re: Simple returns are broken in gcc 3.X
Date: Tue, 31 Jul 2001 16:37:00 -0000	[thread overview]
Message-ID: <20010731163747.B4712@redhat.com> (raw)
In-Reply-To: <200107312306.f6VN6PrE022104@hiauly1.hia.nrc.ca>

On Tue, Jul 31, 2001 at 07:06:25PM -0400, John David Anglin wrote:
> In looking at thread_prologue_and_epilogue_insns, I am having
> difficulty understanding how "returns" are generated when an exit
> block has no non-fake predecessors or no fall-thru predecessor.

They aren't generated in this case because that means that the
function doesn't return (normally) at all.  Perhaps that bit is
deserving of a comment...

There are two other kinds of edges that can come to EXIT_BLOCK:

  (1) If EDGE_ABNORMAL_CALL, then we exit the function by a sibling call.
  (2) If !EDGE_FALLTHRU, then we exit via a return insn.  Given that
      we're removing HAVE_return generation from early in the compiler,
      this should no longer happen at this point.


r~

  reply	other threads:[~2001-07-31 16:37 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2001-07-30 15:33 John David Anglin
2001-07-30 19:30 ` Richard Henderson
2001-07-30 20:38   ` John David Anglin
2001-07-30 23:16     ` Richard Henderson
2001-07-31  8:03       ` John David Anglin
2001-07-31  9:56         ` Richard Henderson
2001-07-31 10:39           ` John David Anglin
2001-07-31 13:13             ` Richard Henderson
2001-07-31 13:43               ` John David Anglin
2001-07-31 13:49                 ` Richard Henderson
2001-07-31 16:08                   ` John David Anglin
2001-07-31 16:37                     ` Richard Henderson [this message]
     [not found] <no.id>
2001-08-09 15:12 ` John David Anglin
2001-08-09 15:48   ` Richard Henderson

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=20010731163747.B4712@redhat.com \
    --to=rth@redhat.com \
    --cc=dave@hiauly1.hia.nrc.ca \
    --cc=gcc@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).