Re: SSA-form and cmove

Hello!


Tommy Hoffner <tommy.hoffner@softlab.ericsson.se> wrote:
>[... conditional move vs. SSA ...]


Couldn't this be handled like just another operator, just like
plus or something like that?


i.e. (like v_new := v_old1 + v_old2)
v_new:= condition ? v_old1 : v_old2


(and cmove dest, src, condition is just
dest_new:= condition ? src : dest_old with a desire to
coalesce dest_new and dest_old).


In this view, I don't see the need for a phi-node there, however,
transformations should know that if they can prove condition is
true, that's equivalent to dest_new := src (and dest_old is dead),
and if condition is false, that's dest_new := dest_old (and src is dead).


Kind regards,


Hannah.

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