Ada bootstrap broken on x86 and x86_64

[Jan Hubicka]

>     this should fix the problem.  I think that the actual value of ADDR_EXPR
>     (VIEW_CONVERT_EXPR (something)) is equivalent to ADDR_EXPR (something)
>     so I can just ignore it when computing the offsets.
> 
> Yes, but a lot of code code in peel_address looks quite wrong to me.  You
> should never use TREE_INT_CST_LOW without checking that there's no high part
> set: that's what the function tree_low_cst is all about.  I added that
> function back in March of 2000: nobody should be using TREE_CST_CST_LOW in
> this way.
> 
> Moreover, the offset for a COMPONENT_REF must include DECL_FIELD_OFFSET and
> for an ARRAY_REF, you have to take into account the lower bound.  he new
> functions in stor-layout.c (array_ref_low_bound, etc) should be used for this.
> 
> But why not simply use get_inner_reference so that everybody finds offsets
> the same way?  The bug with VIEW_CONVERT_EXPR couldn't have occurred if that
> were used.

Well, the code is not mine, I just promised to fix bugs while Zdenek is
away.  However I am just testing the attached patch.  Does it appear
sane?

thanks,
Honza

Index: tree-ssa-loop-ivopts.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/tree-ssa-loop-ivopts.c,v
retrieving revision 2.3
diff -c -3 -p -r2.3 tree-ssa-loop-ivopts.c
*** tree-ssa-loop-ivopts.c	6 Sep 2004 18:38:27 -0000	2.3
--- tree-ssa-loop-ivopts.c	6 Sep 2004 22:13:06 -0000
*************** force_var_cost (struct ivopts_data *data
*** 2513,2566 ****
  static tree
  peel_address (tree addr, unsigned HOST_WIDE_INT *diff)
  {
!   tree off, size;
!   HOST_WIDE_INT bit_offset;
! 
!   switch (TREE_CODE (addr))
!     {
!     case SSA_NAME:
!     case INDIRECT_REF:
!     case BIT_FIELD_REF:
!     case VAR_DECL:
!     case PARM_DECL:
!     case RESULT_DECL:
!     case STRING_CST:
!     case REALPART_EXPR:
!     case IMAGPART_EXPR:
!       return NULL_TREE;
! 
!     case COMPONENT_REF:
!       off = DECL_FIELD_BIT_OFFSET (TREE_OPERAND (addr, 1));
!       bit_offset = TREE_INT_CST_LOW (off);
! 
!       if (bit_offset % BITS_PER_UNIT)
! 	abort ();
!       
!       if (diff)
! 	*diff += bit_offset / BITS_PER_UNIT;
! 
!       return TREE_OPERAND (addr, 0);
! 
!     case ARRAY_REF:
!       off = TREE_OPERAND (addr, 1);
! 
!       if (diff)
! 	{
! 	  if (!cst_and_fits_in_hwi (off))
! 	    return NULL_TREE;
! 
! 	  size = TYPE_SIZE_UNIT (TREE_TYPE (addr));
! 	  if (!cst_and_fits_in_hwi (size))
! 	    return NULL_TREE;
! 
! 	  *diff += TREE_INT_CST_LOW (off) * TREE_INT_CST_LOW (size);
! 	}
! 
!       return TREE_OPERAND (addr, 0);
! 
!     default:
!       abort ();
!     }
  }
  
  /* Checks whether E1 and E2 have constant difference, and if they do,
--- 2513,2532 ----
  static tree
  peel_address (tree addr, unsigned HOST_WIDE_INT *diff)
  {
!   HOST_WIDE_INT bitsize;
!   HOST_WIDE_INT bitpos;
!   tree offset;
!   enum machine_mode mode;
!   int unsignedp;
!   int volatilep;
!   tree obj;
! 
!   obj = get_inner_reference (addr, &bitsize, &bitpos, &offset, &mode, &unsignedp, &volatilep);
!   if (bitpos % BITS_PER_UNIT || offset)
!     return NULL_TREE;
!   if (*diff)
!     *diff += bitpos / BITS_PER_UNIT;
!   return obj;
  }
  
  /* Checks whether E1 and E2 have constant difference, and if they do,