On 4/23/2012 2:13 PM, Shmuel Metz (Seymour J.) wrote:
In<[email protected]>, on 04/21/2012
at 01:40 PM, Edward Jaffe<[email protected]> said:
Good compiler optimization depends on the compiler understanding
what your code is attempting to do and structured, GOTO-less, code
is FAR easier to optimize than its GOTO-laden counterparts.
That's an issue for ALTER and its equivalents in other languages, not
for the GOTO itself.
You might find the following of interest:
Wolfgang Gellerich, Markus Kosiol and Erhard Plödereder, "Where does GOTO Go
to?", Reliable Software Technologies — Ada-Europe '96, Montreux, Switzerland,
June 10–14, 1996 Proceedings, Lecture Notes in Computer Science, Volume
1088/1996, pp. 385-395
This paper documents the disastrous effects GOTO can have on compiler
optimization for RISC, superscalar, out-of-order execution and other
non-obvious, but important execution efficiencies of which optimizers are
increasingly aware. It finds that GOTO is most often used when the programmer is
attempting to write more efficient code yet tends to have exactly the opposite
effect.
--
Edward E Jaffe
Phoenix Software International, Inc
831 Parkview Drive North
El Segundo, CA 90245
310-338-0400 x318
[email protected]
http://www.phoenixsoftware.com/
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