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From: Roman Shaposhnick <rvs@sun.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@cse.psu.edu>
Subject: Re: [9fans] speaking of kenc
Date: Thu,  3 May 2007 19:20:20 -0700	[thread overview]
Message-ID: <1178245220.16650.1845.camel@work.sfbay.sun.com> (raw)
In-Reply-To: <20070503191149.G22416@orthanc.ca>

On Thu, 2007-05-03 at 19:12 -0700, Lyndon Nerenberg wrote:
> >  As far as I can tell C (as in language) has always been a sort of
> > a cross-paltform assembler. Its just sometimes you need hooks
> > to the native one. You might disagree -- but I still do code in
> > assembly.
> 
> That's called as(1).

  On any architecture with a non-trivial register allocation, the above
statement does not apply. 
As far as performance goes you might be better off not using assembler
to begin with. Compilers (at least the ones I work on) are quite smart
in how they use precious resource such as registers, and unless you
can hide everything away on the other side of the 'call' op you'd
be in trouble mixing your code with what compiler had generated for
you. GCC style asm inlines play nice with things like register 
allocator and instruction scheduler, where .s files don't.

>    I think 3B2 code deserves its own place in hell.  Poring over the
>    ESS#5 code, someone found that there were lots of strcmp(p, "f(")
>    == 0 checks (I may have gotten the exact string wrong but it's
>    close).  It took us a while to figure out why.  Apparently, location
>    0 on the 3b had the 3 bytes 'f' '(' '\0', someone noticed that when
>    programs blew up they were pointing to "f(", and the worlds most
>    amazing kludge for detecting nil pointers was born.

  What's 3B3 and ESS#5 ? ;-)

Thanks,
Roman.



  reply	other threads:[~2007-05-04  2:20 UTC|newest]

Thread overview: 149+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-04-27  3:08 erik quanstrom
2007-04-27  3:44 ` David Leimbach
2007-04-27  4:56   ` Bruce Ellis
2007-04-27  6:21     ` Skip Tavakkolian
2007-04-27  4:54 ` Joel C. Salomon
2007-04-27  4:58   ` Bruce Ellis
2007-04-27 11:00   ` Charles Forsyth
2007-04-27 13:49     ` David Leimbach
2007-04-27 16:23       ` Douglas A. Gwyn
2007-04-29  2:02         ` erik quanstrom
2007-04-29  2:55           ` Tim Wiess
2007-04-29  6:42             ` Uriel
2007-04-29 20:47           ` Charles Forsyth
2007-04-30  8:29           ` Douglas A. Gwyn
2007-04-30 13:08             ` Uriel
2007-05-01  0:22             ` erik quanstrom
2007-05-01 14:45               ` Jon Snader
2007-05-01 14:56                 ` Devon H. O'Dell
2007-05-01 15:12                   ` erik quanstrom
2007-05-01 15:29                     ` Devon H. O'Dell
2007-05-01 21:32                   ` Jon Snader
2007-05-02  0:04                   ` Derek Fawcus
2007-05-02  8:44                     ` Charles Forsyth
2007-05-01 15:51                 ` Anthony Sorace
2007-05-02  8:32                   ` Douglas A. Gwyn
2007-05-02  9:00                     ` Steve Simon
2007-05-03  1:32                       ` David Arnold
2007-05-03  3:39                         ` Adrian Tritschler
2007-05-03  3:57                           ` Paul Lalonde
2007-05-03  4:11                             ` Federico Benavento
2007-05-03 13:34                               ` Anthony Sorace
2007-05-03 22:04                               ` LiteStar numnums
2007-05-04  1:45                               ` Roman Shaposhnick
2007-05-04  1:51                                 ` Lyndon Nerenberg
2007-05-04  2:00                                 ` erik quanstrom
2007-05-04  2:08                                   ` Roman Shaposhnick
2007-05-04  2:12                                     ` Lyndon Nerenberg
2007-05-04  2:20                                       ` Roman Shaposhnick [this message]
2007-05-04  2:35                                         ` Lyndon Nerenberg
2007-05-04  6:53                                           ` Bruce Ellis
2007-05-05  4:49                                             ` Roman Shaposhnick
2007-05-05  5:11                                           ` Roman Shaposhnick
2007-05-05  5:14                                             ` Bruce Ellis
2007-05-05 18:52                                               ` erik quanstrom
2007-05-05 19:13                                                 ` lucio
2007-05-05 23:09                                                   ` Bruce Ellis
2007-05-06  1:24                                                     ` Rogelio Serrano
2007-05-06  4:08                                                   ` erik quanstrom
2007-05-06  4:53                                                     ` W B Hacker
2007-05-06  5:01                                                     ` lucio
2007-05-06  5:01                                                     ` Rogelio Serrano
2007-05-06  5:07                                                       ` Rogelio Serrano
2007-05-06  5:15                                                         ` lucio
2007-05-06  5:37                                                           ` Bruce Ellis
2007-05-06  6:30                                                           ` Rogelio Serrano
2007-05-06  6:46                                                             ` lucio
2007-05-06  6:49                                                             ` lucio
2007-05-06  7:35                                                               ` Rogelio Serrano
2007-05-06  6:51                                                             ` W B Hacker
2007-05-06 10:25                                                               ` Rogelio Serrano
2007-05-06  6:04                                                         ` Skip Tavakkolian
2007-05-06  7:24                                                           ` lucio
2007-05-06 11:47                                                             ` Bruce Ellis
2007-05-07  1:55                                                           ` Roman Shaposhnik
2007-05-06  5:12                                                       ` lucio
2007-05-06 13:18                                                         ` Richard Miller
2007-05-06 20:23                                                           ` Roman Shaposhnik
2007-05-07  1:57                                                         ` Roman Shaposhnik
2007-05-07  4:29                                                           ` W B Hacker
2007-05-07 15:08                                                             ` Tim Wiess
2007-05-06  5:15                                                       ` W B Hacker
2007-05-06  7:43                                                         ` Rogelio Serrano
2007-05-06  8:02                                                           ` W B Hacker
2007-05-06  8:12                                                             ` Rogelio Serrano
2007-05-06  9:00                                                               ` W B Hacker
2007-05-06  8:03                                                           ` lucio
2007-05-06  8:42                                                             ` Rogelio Serrano
2007-05-06 10:20                                                               ` matt
2007-05-06 10:29                                                                 ` Rogelio Serrano
2007-05-06  9:09                                                             ` W B Hacker
2007-05-06  5:10                                                     ` W B Hacker
2007-05-06  5:32                                                       ` lucio
2007-05-06  6:18                                                         ` Rogelio Serrano
2007-05-06  6:30                                                           ` W B Hacker
2007-05-06  6:21                                                         ` W B Hacker
2007-05-07  1:47                                                     ` Roman Shaposhnik
2007-05-06  1:13                                               ` Rogelio Serrano
2007-05-06  3:31                                                 ` W B Hacker
2007-05-06  4:10                                                 ` erik quanstrom
2007-05-06  4:55                                                   ` Rogelio Serrano
2007-05-06  5:10                                                     ` lucio
2007-05-06  6:05                                                       ` W B Hacker
2007-05-06  8:45                                                         ` matt
2007-05-06  6:45                                                       ` Rogelio Serrano
2007-05-06  6:52                                                         ` lucio
2007-05-06  7:09                                                           ` W B Hacker
2007-05-06  7:34                                                             ` Rogelio Serrano
2007-05-06  7:49                                                               ` W B Hacker
2007-05-06  7:54                                                               ` lucio
2007-05-06  8:35                                                                 ` Rogelio Serrano
2007-05-06  7:40                                                             ` lucio
2007-05-06  8:59                                                               ` W B Hacker
2007-05-06  7:03                                                         ` W B Hacker
2007-05-06  5:21                                                 ` Bruce Ellis
2007-05-06  7:01                                                   ` Rogelio Serrano
2007-05-05  5:30                                             ` lucio
2007-05-04  2:16                                     ` erik quanstrom
2007-05-04  9:24                                       ` C H Forsyth
2007-05-04 11:18                                         ` erik quanstrom
2007-05-04 16:19                                         ` Paul Lalonde
2007-05-04 21:58                                           ` Dave Eckhardt
2007-05-04 22:27                                             ` Paul Lalonde
2007-05-04  8:46                                 ` Douglas A. Gwyn
2007-05-05  4:47                                   ` Roman Shaposhnick
2007-05-02  8:33                 ` Douglas A. Gwyn
2007-05-02 11:25                   ` Jon Snader
2007-05-02  8:33               ` Douglas A. Gwyn
2007-05-02 11:30                 ` erik quanstrom
2007-04-27 16:21     ` Douglas A. Gwyn
2007-04-27 11:12   ` Charles Forsyth
2007-04-27 11:46   ` erik quanstrom
2007-04-27 14:21     ` Joel C. Salomon
2007-04-27 14:26       ` erik quanstrom
2007-04-27 14:41         ` Rob Pike
2007-04-27 14:55         ` Joel C. Salomon
2007-04-27 15:24           ` erik quanstrom
2007-04-27 15:53           ` C H Forsyth
2007-04-28  9:09   ` ron minnich
2007-04-28  9:17     ` Lucio De Re
2007-04-28 13:48       ` Eric Van Hensbergen
2007-04-28 13:57         ` Lucio De Re
2007-04-28 14:15         ` LiteStar numnums
2007-04-28 21:21         ` Roman Shaposhnik
2007-04-28 21:54           ` ron minnich
2007-04-28 22:33             ` Steve Simon
2007-04-28 15:45     ` Charles Forsyth
2007-04-28 17:58       ` Rodrigo Miranda
2007-04-28 20:12         ` Eric Van Hensbergen
2007-04-28 21:10           ` Roman Shaposhnik
2007-04-28 18:15       ` Lluís Batlle i Rossell
2007-04-29  2:39       ` Joel C. Salomon
2007-04-29 12:41         ` erik quanstrom
2007-04-29 16:00           ` Joel C. Salomon
2007-04-28 21:24     ` Roman Shaposhnik
2007-05-06 12:36 erik quanstrom
2007-05-06 15:18 ` lucio
2007-05-06 16:23   ` W B Hacker
2007-05-06 17:53     ` Benn Newman
2007-05-06 17:56       ` Francisco J Ballesteros

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