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- From: mash@mips.com (John Mashey)
- Newsgroups: comp.arch
- Subject: Re: Natural Word Size (was Re: 32 => 64 Transition
- Message-ID: <l9oirnINN9j7@spim.mips.com>
- Date: 27 Aug 92 03:26:47 GMT
- References: <1992Aug24.191322.14510@bcars64a.bnr.ca> <DOCONNOR.92Aug24135056@potato.sedona.intel.com> <1992Aug25.142208.18792@bcars64a.bnr.ca>
- Organization: MIPS Computer Systems, Inc.
- Lines: 32
- NNTP-Posting-Host: winchester.mti.sgi.com
-
- In article <1992Aug25.142208.18792@bcars64a.bnr.ca> schow@bqneh3.bnr.ca (Stanley T.H. Chow) writes:
- >In article <DOCONNOR.92Aug24135056@potato.sedona.intel.com> doconnor@sedona.intel.com (Dennis O'Connor) writes:
- >>
- >>] Clearly, for an archtecture family, there is *no* natural word size. At
- >>] best, there is a "prefered" size that is defined by the architecture that
-
- I agree with Stanley: I have some skepticism about the faith placed in the
- meaning of "natural" word sizes, especially since:
- a) Compilers *usually* target an architecture family in a consistent
- way ... but optimality of choice depends on the specific
- implementation within a family.
- b) At least some of this derives from wording inherited from the
- past which may well have been purposefully fuzzy, i.e.:
-
- - In the C Reference Manual, 1974, there is no menion of "natural"
- sizes of anything.... in fact, ints are described as:
- "Integers (int) are represented in 16-bit 2's complement notation."
- (of course, to be fair, this was before longs existed ...)
- - In K&R (2nd edition) it says:
- "int an integer, typically reflecting the natural size
- of integers in the host machine"
- and later:
- "int will normally be the natural size for a particular machine."
-
- - If you know K/R's normal parsimony of words, the inclusion of
- the qualifiers "typically" and "normally" may be significant.... :-)
- n
- --
- -john mashey DISCLAIMER: <generic disclaimer, I speak for me only, etc>
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