Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site decvax.UUCP Path: utzoo!watmath!clyde!floyd!harpo!decvax!minow From: minow@decvax.UUCP (Martin Minow) Newsgroups: net.lang.c Subject: Can ANSI Standard C be "Optimized" Message-ID: <404@decvax.UUCP> Date: Mon, 12-Mar-84 20:23:49 EST Article-I.D.: decvax.404 Posted: Mon Mar 12 20:23:49 1984 Date-Received: Tue, 13-Mar-84 20:38:57 EST References: <6061@decwrl.UUCP> Organization: DEC UNIX Engineering Group Lines: 20 In the interesting and well-detailed series of optimization comparisons between C and Bliss, it was pointed out several times that Bliss performs many multi-statement optimizations the C ignores. If I read the Draft ANSI Standard correctly, it would seem to preclude any optimizations across statement (;) boundaries. Thus, simple for satements cannot take advantage of loop control instructions such as SOB on the PDP-11. Therefore, many of the failings of the C optimizers are inherent in the definition of the language, and not simply due to laziness on the part of the compiler writers. (And, no, I don't know why this restriction was put in the draft standard.) Martin Minow decvax!minow