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Re: C Macro define contain symbol #

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Phil Carmody <thefatphil_demunged@yahoo.co.uk> writes:
> Keith Thompson <kst-u@mib.org> writes:
>> (The system was the Cray T90.  The word size was 64 bits, and there was
>> no hardware support for byte addressing.  Byte addresses were
>> implemented in software by storing an offset in the high-order 3 bits of
>> a 64-bit pointer.)
>
> I presume the Cray T3E is the similar, as that was based on DEC's
> 21164 which only had word (64 bit) memory access, and then arbitrary
> byte shuffle/extraction operations to extract the byte you're
> interested in. That used to throw a few bubbles in the pipeline, so
> you didn't do it unless you absolutely needed it.
>
> Not that I ever used mine (21164, not T3E) for anything
> apart from FP stuff, so I'm not speaking from experience,
> just hearsay.

No, it wasn't (I worked on both).  The T3E used the DEC Alpha.
The C compiler had 8-bit char, 32-bit short, and 64-bit int and long.
It may have required extra work to access bytes (I never looked into
it that deeply, but machine addresses pointed to bytes, not words,
so there was no special format for void* vs. int*.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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C Macro define contain symbol # Wang WolfLouis <wolflouiswang@gmail.com> - 2011-09-13 02:47 -0700
  Re: C Macro define contain symbol # Noob <root@127.0.0.1> - 2011-09-13 13:14 +0200
  Re: C Macro define contain symbol # Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-09-13 07:55 -0400
    Re: C Macro define contain symbol # Roberto Waltman <usenet@rwaltman.com> - 2011-09-13 08:24 -0400
      Re: C Macro define contain symbol # Keith Thompson <kst-u@mib.org> - 2011-09-13 11:12 -0700
        Re: C Macro define contain symbol # Keith Thompson <kst-u@mib.org> - 2011-09-13 20:19 -0700
          Re: C Macro define contain symbol # Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-09-16 00:43 +0300
            Re: C Macro define contain symbol # Keith Thompson <kst-u@mib.org> - 2011-09-15 18:34 -0700
        Re: C Macro define contain symbol # Richard Damon <news.x.richarddamon@xoxy.net> - 2011-09-13 22:51 -0400
          Re: C Macro define contain symbol # Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-09-14 12:16 +0100
      Re: C Macro define contain symbol # tom st denis <tom@iahu.ca> - 2011-09-13 11:20 -0700
      Re: C Macro define contain symbol # Ian Collins <ian-news@hotmail.com> - 2011-09-14 07:55 +1200
      Re: C Macro define contain symbol # Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-09-14 07:58 -0400
        Re: C Macro define contain symbol # Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-09-14 14:54 +0000
      Re: C Macro define contain symbol # Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-09-16 00:34 +0300
        Re: C Macro define contain symbol # Nobody <nobody@nowhere.com> - 2011-09-16 12:07 +0100
    Re: C Macro define contain symbol # "BartC" <bc@freeuk.com> - 2011-09-13 13:50 +0100
      Re: C Macro define contain symbol # James Kuyper <jameskuyper@verizon.net> - 2011-09-13 08:59 -0400
        Re: C Macro define contain symbol # Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-09-14 15:02 +0000
  Re: C Macro define contain symbol # Kenneth Brody <kenbrody@spamcop.net> - 2011-09-13 16:54 -0400

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