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Re: Issue: DEFINE-OPTIMIZER
- To: Rob.MacLachlan%WB1.CS.CMU.EDU@multimax
- Subject: Re: Issue: DEFINE-OPTIMIZER
- From: Dan L. Pierson <pierson%mist@multimax.ARPA>
- Date: Fri, 07 Oct 88 13:56:39 EDT
- Cc: cl-compiler%sail.stanford.edu@Multimax
- In-reply-to: Your message of Fri, 07 Oct 88 13:03:41 -0400. <8810071706.AA01283@multimax.ARPA>
Consider also an implementation that transforms (1+ x) to the canonical
form (+ x 1), and a user "optimizer" that transforms (+ x 1) to
This problem goes away if we're willing to accept the restriction that
user-defined optimzers are a strict prepass to compiler optimzers.
This seems reasonable to me; it still lets me do almost anything that
I can think about portably. Of course it may lose if I transform the
code to make superior implementation optimization impossible, but that
can be covered by a warning.