From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeffrey A Law <law@hurl.cygnus.com>
To: Richard Henderson <rth@cygnus.com>
Cc: Jamie Lokier <egcs@tantalophile.demon.co.uk>, Marc Lehmann <pcg@goof.com>, egcs@cygnus.com
Subject: Re: GCC 2.7.2.3 good, EGCS 1.0.3 bad for x86 subtract then test 
Date: Wed, 23 Dec 1998 20:57:00 -0000
Message-id: <12174.914475308@hurl.cygnus.com>
References: <19981223141815.C12309@dot.cygnus.com>
X-SW-Source: 1998-12/msg00896.html

  In message < 19981223141815.C12309@dot.cygnus.com >you write:
  > On Mon, Dec 21, 1998 at 10:52:13AM +0000, Jamie Lokier wrote:
  > > Here's the example program:
  > > 
  > > 	extern void a (void);
  > > 
  > > 	void f (int x, int y)
  > > 	{
  > > 	  if ((x -= y) >= 0)
  > > 	    a ();
  > > 	}
  > 
  > This is solved by a patch Jeff sent me just yesterday.
Yea.  But it seems to generally create worse code -- too aggressive about
copying the source to the destination.  Some tweaking of the heuristic for
when to copy the source to the destination may be needed to make the change
generally useful.

jeff