This is the mail archive of the gcc@gcc.gnu.org mailing list for the GCC project.

Index Nav:	[Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav:	[Date Prev] [Date Next]	[Thread Prev] [Thread Next]
Other format:	[Raw text]

Re: Help with RTL expand and a builtins

From: Segher Boessenkool <segher at kernel dot crashing dot org>
To: Martin Liška <mliska at suse dot cz>
Cc: GCC Development <gcc at gcc dot gnu dot org>
Date: Tue, 18 Jul 2017 09:49:26 -0500
Subject: Re: Help with RTL expand and a builtins
Authentication-results: sourceware.org; auth=none
References: <1642fa8f-e881-03e0-0e3d-d5a91fa6397e@suse.cz> <680a57fa-5548-0412-27c4-9660e71145ee@suse.cz>

On Tue, Jul 18, 2017 at 12:49:06PM +0200, Martin Liška wrote:
> Solved, tail call was responsible for dead RTL instructions.

This seems similar to https://gcc.gnu.org/ml/gcc-patches/2017-07/msg00362.html
then.  Is it?

There are many cases where we generated dead code during expand on
purpose (some just laziness, some to avoid code complications).
Because of this it is hard to detect where we generate dead code that
is just plain wrong (should not be dead).  And such things aren't
trivial to debug :-(


Segher

Follow-Ups:
- Re: Help with RTL expand and a builtins
  - From: Martin Liška

References:
- Help with RTL expand and a builtins
  - From: Martin Liška
- Re: Help with RTL expand and a builtins
  - From: Martin Liška

Index Nav:	[Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav:	[Date Prev] [Date Next]	[Thread Prev] [Thread Next]