>
> Hmm, maybe I can genericise the conversion for case when second operand
> is INTEGER_CST or one of operands is NOP_EXPR that will get folded away
> then and remove the case above.
> I can't think of any reason why one would require checking the size
> except for the case that someone was thinking of C pointer + operator
> that is multiplied by the pointed to size...
> >
> > Otherwise this is ok if it passes testing.
> >
> > + /* Convert (A+offset into &A->field_of_type_and_offset. */
> >
> > parenthesis mismatch.
>
> Uh, I will fix it and commit without the hunk handling the conversion
> above and will send updated patch for that.
Hi,
here is the updated patch, bootstrapped/regtested i686-linux, OK?
* fold-const.c (fold_unary): Convert (T1)(X op Y) into
((T1)X op (T1)Y), for pointer type, when one of the new casts will fold
away.
Index: fold-const.c
===================================================================
*** fold-const.c (revision 123674)
--- fold-const.c (working copy)
*************** fold_unary (enum tree_code code, tree ty
*** 7808,7831 ****
}
}
! /* Convert (T1)((T2)X op Y) into (T1)X op Y, for pointer types T1 and
! T2 being pointers to types of the same size. */
! if (POINTER_TYPE_P (type)
&& BINARY_CLASS_P (arg0)
! && TREE_CODE (TREE_OPERAND (arg0, 0)) == NOP_EXPR
! && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (arg0, 0))))
{
tree arg00 = TREE_OPERAND (arg0, 0);
! tree t0 = type;
! tree t1 = TREE_TYPE (arg00);
! tree tt0 = TREE_TYPE (t0);
! tree tt1 = TREE_TYPE (t1);
! tree s0 = TYPE_SIZE (tt0);
! tree s1 = TYPE_SIZE (tt1);
!
! if (s0 && s1 && operand_equal_p (s0, s1, OEP_ONLY_CONST))
! return build2 (TREE_CODE (arg0), t0, fold_convert (t0, arg00),
! TREE_OPERAND (arg0, 1));
}
/* Convert (T1)(~(T2)X) into ~(T1)X if T1 and T2 are integral types
--- 7807,7826 ----
}
}
! /* Convert (T1)(X op Y) into ((T1)X op (T1)Y), for pointer type,
! when one of the new casts will fold away. Conservatively we assume
! that this happens when X or Y is NOP_EXPR or Y is INTEGER_CST. */
! if (POINTER_TYPE_P (type) && POINTER_TYPE_P (arg0)
&& BINARY_CLASS_P (arg0)
! && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST
! || TREE_CODE (TREE_OPERAND (arg0, 0)) == NOP_EXPR
! || TREE_CODE (TREE_OPERAND (arg0, 1)) == NOP_EXPR))
{
tree arg00 = TREE_OPERAND (arg0, 0);
! tree arg01 = TREE_OPERAND (arg0, 1);
!
! return fold_build2 (TREE_CODE (arg0), type, fold_convert (type, arg00),
! fold_convert (type, arg01));
}