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Re: English Idiom in Unix: Directory Recursively

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Jonathan de Boyne Pollard wrote:

>> In the microcontroller world, the big performance hits come from the
>> fact that the only available compilers are for C and sometimes C++.
>> (And nobody uses assembly language except for the very little jobs.)
>> The nature of the C language prevents compilers from doing
>> optimisations that are standard in compilers for high-level
>> languages. Most C compilers will, for example, always pass
>> parameters on the stack, despite the generous supply of registers
>> available in newer hardware. 

I'm not sure this is a limitation of the C language. To me it is, if
this is indeed correct, a limitation of the currently available crop of
C compilers. ("Most" is always a difficult affirmation. You'd have to
review "all" in order to be able to say "most". And you'd forget about
relative importance of individual compilers.)

> However, some C compilers will *also* have one or more "go faster"
> calling conventions that pass parameters in registers, which can be
> employed.  

Also, some C compilers do "whole program optimization" and with that can
tailor the calling code to the called code. There doesn't seem to be
anything in the C language spec that prohibits such things.

Gerhard

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Re: English Idiom in Unix: Directory Recursively Jonathan de Boyne Pollard <J.deBoynePollard-newsgroups@NTLWorld.COM> - 2011-05-21 09:32 +0100
  Re: English Idiom in Unix: Directory Recursively Lars Enderin <lars.enderin@telia.com> - 2011-05-21 11:52 +0200
    Re: English Idiom in Unix: Directory Recursively Lars Enderin <lars.enderin@telia.com> - 2011-05-21 11:54 +0200
      Re: English Idiom in Unix: Directory Recursively Lars Enderin <lars.enderin@telia.com> - 2011-05-21 11:56 +0200
  Re: English Idiom in Unix: Directory Recursively Gerhard Fiedler <gelists@gmail.com> - 2011-05-21 11:33 -0300
    Re: English Idiom in Unix: Directory Recursively Seebs <usenet-nospam@seebs.net> - 2011-05-21 18:37 +0000
    Re: English Idiom in Unix: Directory Recursively Nobody <nobody@nowhere.com> - 2011-05-22 14:20 +0100

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