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Re: [patch] PR 15785
Roger Sayle <roger@eyesopen.com> writes:
> On 13 Feb 2005, James A. Morrison wrote:
> + if (TREE_CODE (arg0) == BIT_NOT_EXPR)
> + return fold (build2 (PLUS_EXPR, type, TREE_OPERAND (arg0, 0),
> + build_int_cst (NULL_TREE, 1)));
>
> This integer constant needs to be of type "type", not NULL_TREE.
> And likewise for the other place you call build_int_cst.
>
> You might also want to test for (A + -1) as a synonym of A - 1.
> I'm unsure if we canonicalize these to the same thing, and if so
> which form we prefer, but testing for both seems sensible.
>
> Roger
We don't seem to canonicalize this as the generic dump of x + (-1) is
x + -1.
--
Thanks,
Jim
http://www.student.cs.uwaterloo.ca/~ja2morri/
http://phython.blogspot.com
http://open.nit.ca/wiki/?page=jim