Re: optimization/8634: [3.2/3.3 regression] incorrect code for inlining of memcpy under -O2

[Janis Johnson <janis187@us.ibm.com>]

The following reply was made to PR optimization/8634; it has been noted by GNATS.

From: Janis Johnson <janis187@us.ibm.com>
To: gcc-gnats@gcc.gnu.org, gcc-prs@gcc.gnu.org, duchier@ps.uni-sb.de,
   gcc-bugs@gcc.gnu.org, nobody@gcc.gnu.org
Cc:  
Subject: Re: optimization/8634: [3.2/3.3 regression] incorrect code for inlining 
 of memcpy under -O2
Date: Mon, 23 Dec 2002 16:37:21 -0800

 The regression reported in PR optimization/8634 showed up
 starting with this patch (strange but true):
 
 Fri Dec 21 23:30:14 CET 2001  Jan Hubicka  <jh@suse.cz>
      * i386.h (TARGET_CPU_DEFAULT_pentium_mmx): New.
     (TARGET_CPU_DEFAULT_*): Renumber.
 
 I used this test case that Wolfgang provided.  It aborts
 when the wrong code is generated for -O2 on i686-linux:
 
 --------------
 /* incorrect code for inlining of memcpy under -O2 */
 
 #include <string.h>
 #include <stdlib.h>
 
 int
 main ()
 {
   int i;
   char buffer[8];
   const char head[8] =
     { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H' };
   memcpy (buffer, head, 8);
   for (i = 0; i < 8; i++)
     if (head[i] != buffer[i])
       abort ();
   return 0;
 }
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 http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=8634