Re: ICE building Linux 2.4.20 sched.c on x86

[Jim Wilson <wilson at tuliptree dot org>]

Dara Hazeghi wrote:
> we've just now had our third submission of this particular bug to 
> bugzilla (10890 is the original, 11007 and 11053 are the duplicate). 

This is my fault.  This was introduced by a patch of mine here:
  http://gcc.gnu.org/ml/gcc/2002-10/msg00284.html
This adds some consistency checking code to reload so it would abort 
instead of silently generating bad code.  However, in this case, the 
code is OK.  We have two reloads with the same inputs that aren't 
combined, so they don't conflict with each other.

The following patch seems to solve the problem.  I verify that it works 
for the original testcase that prompted the original patch.  I haven't 
done a bootstrap test yet.

Jim
2003-06-06  James E Wilson  <wilson@tuliptree.org>

	* reload1.c (merge_assigned_reloads): Abort only if two reloads have
	different in fields.

Index: reload1.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/reload1.c,v
retrieving revision 1.394
diff -p -r1.394 reload1.c
*** reload1.c	11 May 2003 02:15:24 -0000	1.394
--- reload1.c	6 Jun 2003 07:01:14 -0000
*************** merge_assigned_reloads (insn)
*** 6138,6150 ****
  		       ? RELOAD_FOR_OTHER_ADDRESS : RELOAD_OTHER);
  
  		  /* Check to see if we accidentally converted two reloads
! 		     that use the same reload register to the same type.
! 		     If so, the resulting code won't work, so abort.  */
  		  if (rld[j].reg_rtx)
  		    for (k = 0; k < j; k++)
  		      if (rld[k].in != 0 && rld[k].reg_rtx != 0
  			  && rld[k].when_needed == rld[j].when_needed
! 			  && rtx_equal_p (rld[k].reg_rtx, rld[j].reg_rtx))
  			abort ();
  		}
  	}
--- 6138,6152 ----
  		       ? RELOAD_FOR_OTHER_ADDRESS : RELOAD_OTHER);
  
  		  /* Check to see if we accidentally converted two reloads
! 		     that use the same reload register with different inputs
! 		     to the same type.  If so, the resulting code won't work,
! 		     so abort.  */
  		  if (rld[j].reg_rtx)
  		    for (k = 0; k < j; k++)
  		      if (rld[k].in != 0 && rld[k].reg_rtx != 0
  			  && rld[k].when_needed == rld[j].when_needed
! 			  && rtx_equal_p (rld[k].reg_rtx, rld[j].reg_rtx)
! 			  && ! rtx_equal_p (rld[k].in, rld[j].in))
  			abort ();
  		}
  	}