-freduce-all-givs and fortran

[Richard Henderson]

On Thu, Sep 06, 2001 at 10:28:08PM +0200, Toon Moene wrote:
> Somehow, the giv-combine code doesn't examine the base addresses of
> these arrays [quoting swim.f.11.loop]:
[...]
> Giv 80: insn 40 src reg 69 benefit 4 lifetime 8 replaceable
>  mult (4)
>  add  (const (plus (symbol_ref ("com_")) (-4)))
> Giv 88: insn 51 src reg 69 benefit 4 lifetime 3 replaceable
>  mult (4)
>  add  (const (plus (symbol_ref ("com_")) (396)))

Whee.


r~



Index: simplify-rtx.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/simplify-rtx.c,v
retrieving revision 1.41.2.3
diff -c -p -d -r1.41.2.3 simplify-rtx.c
*** simplify-rtx.c	2001/04/05 00:52:19	1.41.2.3
--- simplify-rtx.c	2001/09/06 21:45:16
*************** simplify_binary_operation (code, mode, o
*** 1110,1115 ****
--- 1110,1137 ----
  	       return simplify_gen_binary (AND, mode, op0,
  					   gen_rtx_NOT (mode, XEXP (op1, 0)));
  	   }
+ 
+ 	  /* Simplify operations with constants containing embedded offsets.  */
+ 	  if (GET_CODE (op0) == CONST)
+ 	    {
+ 	      tem = simplify_binary_operation (code, mode, XEXP (op0, 0), op1);
+ 	      if (tem)
+ 		{
+ 		  if (CONSTANT_P (op1) && ! CONSTANT_P (tem))
+ 		    tem = gen_rtx_CONST (mode, tem);
+ 		  return tem;
+ 		}
+ 	    }
+ 	  if (GET_CODE (op1) == CONST)
+ 	    {
+ 	      tem = simplify_binary_operation (code, mode, op0, XEXP (op1, 0));
+ 	      if (tem)
+ 		{
+ 		  if (CONSTANT_P (op0) && ! CONSTANT_P (tem))
+ 		    tem = gen_rtx_CONST (mode, tem);
+ 		  return tem;
+ 		}
+ 	    }
  	  break;
  
  	case MULT: