flow.c:initialize_uninitialized_subregs

[Andrew Macleod]

>> > failing at its purpose according to the ChangeLog, and that
>> > find_regno_partial needs to dig a little deeper or something.
>> > 
>> > Possibly like this (untested as yet) patch:
>> 
>> Yes, that did the trick.  rtl now looks like it's doing what was
>> intended, and powerpc-linux bootstrap restored.
>> 
>> OK to apply?
>> 
>> > 	* flow.c (find_regno_partial): Return the reg rtx within the
>> > 	partial reg rtx.
>> > 
>> > --- gcc/flow.c~	Wed Dec  5 14:35:03 2001
>> > +++ gcc/flow.c	Thu Dec  6 21:57:37 2001
>> > @@ -1327,7 +1327,7 @@ find_regno_partial (ptr, data)
>> >        case STRICT_LOW_PART:
>> >          if (GET_CODE (XEXP (*ptr, 0)) == REG && REGNO (XEXP (*ptr, 0)) == reg)
>> >  	  {
>> > -	    param->retval = *ptr;
>> > +	    param->retval = XEXP (*ptr, 0);
>> >  	    return 1;
>> >  	  }
>> >  	break;
>> > @@ -1336,7 +1336,7 @@ find_regno_partial (ptr, data)
>> >          if (GET_CODE (SUBREG_REG (*ptr)) == REG 
>> >  	    && REGNO (SUBREG_REG (*ptr)) == reg)
>> >  	  {
>> > -	    param->retval = *ptr;
>> > +	    param->retval = SUBREG_REG (*ptr);
>> >  	    return 1;
>> >  	  }
>> >  	break;
>> > 

David Edelsohn pointed out the failure yesterday afternoon , and I responded with 
the following identical patch which he verified solved the problem.  What I didnt 
notice was that he sent it to the gcc newsgroup rather than bugs/patches. Im 
checking this in since it was the original intent and the final patch was suppose 
to be this way.
Unfortunately, it bootstrapped on x86 and ia64 both ways....

Andrew



	* flow.c (find_regno_partial): Return register, not the expression
	the register is in.


Index: flow.c
===================================================================
RCS file: /cvs/gcc/egcs/gcc/flow.c,v
retrieving revision 1.494
diff -c -p -r1.494 flow.c
*** flow.c	2001/12/05 01:39:41	1.494
--- flow.c	2001/12/05 20:50:13
*************** find_regno_partial (ptr, data)
*** 1327,1333 ****
        case STRICT_LOW_PART:
          if (GET_CODE (XEXP (*ptr, 0)) == REG && REGNO (XEXP (*ptr, 0)) == reg)
  	  {
! 	    param->retval = *ptr;
  	    return 1;
  	  }
  	break;
--- 1327,1333 ----
        case STRICT_LOW_PART:
          if (GET_CODE (XEXP (*ptr, 0)) == REG && REGNO (XEXP (*ptr, 0)) == reg)
  	  {
! 	    param->retval = XEXP (*ptr, 0);
  	    return 1;
  	  }
  	break;
*************** find_regno_partial (ptr, data)
*** 1336,1342 ****
          if (GET_CODE (SUBREG_REG (*ptr)) == REG 
  	    && REGNO (SUBREG_REG (*ptr)) == reg)
  	  {
! 	    param->retval = *ptr;
  	    return 1;
  	  }
  	break;
--- 1336,1342 ----
          if (GET_CODE (SUBREG_REG (*ptr)) == REG 
  	    && REGNO (SUBREG_REG (*ptr)) == reg)
  	  {
! 	    param->retval = SUBREG_REG (*ptr);
  	    return 1;
  	  }
  	break;