Comments for R. Matthew Emerson

Comment on CCL on x8632: more registers, please by wolf550e

wolf550e — Sat, 20 Sep 2008 03:46:26 +0000

Very interesting.
Win32 uses FS for thread local storage. Did you take the idea from there?
What about doing what GCC does when you specify -fomit-frame-pointer? That should give you a register. Or if you can’t use if, please write another post about it.
Re: presumably cheaper instruction pair. Benchmark! Some legacy x86 instructions are quite slow on modern cpus (core2). The Intel docs are good, but I’d benchmark and possibly even see what the Intel compilers generate to find out what’s best practice for today’s chips.

Comment on Playing sounds from the command line by Alberto

Alberto — Fri, 28 Mar 2008 21:02:15 +0000

YAY! Thank you! Thank you! Thank you!

Comment on Getting disk insertion/removal notifications by Andreas Wacker

Andreas Wacker — Tue, 30 Oct 2007 18:20:49 +0000

you wrote: “Maybe this will help somebody out there”

I would say that this it so perfectly what I was looking for that it is almost scary.

Thank you!

Comment on Clozure CL (née OpenMCL) by Dimiter "malkia" Stanev

Dimiter "malkia" Stanev — Fri, 19 Oct 2007 23:29:40 +0000

OpenMCL runs fine on the PS3 (YellowDog linux) – both 64bit and 32bit.

Comment on Getting disk insertion/removal notifications by rme

rme — Thu, 06 Sep 2007 16:12:40 +0000

You need to add the DiskArbitration.framework to your Xcode project. See this part of the Xcode documentation. If you compile from the command-line, you'd say cc foo.m -framework DiskArbitration -framework Foundation.

Comment on Getting disk insertion/removal notifications by rdw

rdw — Thu, 06 Sep 2007 04:20:12 +0000

Sorry to ask such a basic question, but I am new to XCode and the Mac OS X environment. I’m trying to build your code snippet above, and am getting:

[Session started at 2007-09-05 21:14:58 -0700.]
ZeroLink: unknown symbol ‘_DASessionCreate’

DiskInsertion has exited due to signal 6 (SIGABRT).

I tried additional includes…
#include
#include

Any tips would be greatly appreciated. Trying to build a simple daemon to perform an action when a particular volume is mounted… and your code is a good example. Unfortunately I am unable to really get started.

Thanks.

rdw

Comment on Probably prime numbers by msingh

msingh — Sat, 09 Jun 2007 12:01:18 +0000

Nice work.. but i think there is a small bug in your code.
The line (let ((w (+ 1 (random (- n 2))))) should probably be (1+ (random (- n 1))) because CLR specifies a random integer a in [1, n-1]. Your’s wont admit n-1.

Comment on Probably prime numbers by Andras Simon

Andras Simon — Mon, 12 Mar 2007 15:49:33 +0000

Nice! But that

(if (/= d 1)
        t
        nil)

hurts my eyes. I'd also move the local variables into the loop, as in

(defun witness (a n)
  (let ((b (- n 1)))
    (loop for i from (integer-length b) downto 0
          for d = 1 then (mod (* d d) n)
          for x = d
          do
          (when (and (= d 1) (/= x 1) (/= x (- n 1)))
            (return-from witness t))
          (when (logbitp i b)
            (setf d (mod (* d a) n)))
          finally (return (/= d 1)))))