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Re: SSA usage question


    [ It has been impossible for me to recreate the thread of this
    discussion.  Kenner, please fix your mail program! ]

That's on my list.  I have to be sure I have the right sources to
start from first.

    GIMPLE is not supposed to be powerful.  It's supposed to be really
    simplistic to cater to the optimizers.  You are supposed to expose
    everything in excruciating detail.

That's fine for scalars, but for aggregates, the whole point is that the
structure of the access is what contains the information.  If you break it
down, you lose that information.

With scalars, if you have an extra copy, so what.

With aggregates, the copy might be prohibitively expensive, involve variable
size temporaries (which the gimplifier doesn't support) or not be permitted
by the language (e.g., limited types in Ada).


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