The D Programming Language (was: Still more new operators)

Wayne A. Throop throopw at xyzzy.UUCP
Mon Mar 7 08:59:44 AEST 1988


> gwyn at brl-smoke.ARPA (Doug Gwyn )
>> henry at utzoo.uucp (Henry Spencer)
>>Bill Wulf [... states ...] of bit-oriented
>>machines [...] "I wish they weren't so damned slow".  I'm afraid
>>I haven't seen anything since that invalidates that assessment.

I have.

> Bit-addressable architectures need not be slow; you could apply the same line
> of reasoning to "prove" that byte-addressability makes a machine too slow,

Exactly so.  The only problem that bit addressability (as opposed to byte
addressability) brings to the game is an eight-times smaller address
space for a given number of bits.  But nobody claims that the
four-or-eight-times smaller address space of byte-granular vs
word-granular architectures means word-granular architectures are the
only viable ones, nor that byte-granular ones are noticeably slower.

And having participated in developing language tools for a bit-granular
addressed architecture, I'll add that bit granularity eliminates a whole
raft of inefficent and ugly kludgerey associated with simulating the bit
granularity needed in so many places.  I'm convinced it's worth it.

But perhaps I'm misunderstanding what Henry means by "bit-oriented"...
I'm arguing only for bit-granular addressing.

--
IBM manuals are written by little old ladies in Poughkeepsie who are
instructed to say nothing specific.
      --- R. T. Lillington
-- 
Wayne Throop      <the-known-world>!mcnc!rti!xyzzy!throopw



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