× The internal search function is temporarily non-functional. The current search engine is no longer viable and we are researching alternatives.
As a stop gap measure, we are using Google's custom search engine service.
If you know of an easy to use, open source, search engine ... please contact support@midrange.com.


  1.  Home
  2. C400-L
  3. November 2003

RE: circular rotate integers


> -----Original Message-----
> From: Gene_Gaunt@xxxxxxxxxxxxxxx [mailto:Gene_Gaunt@xxxxxxxxxxxxxxx]
> 
> What's the best way in C code to left circular rotate an integer?
> as in:   left_rotate( int X = 0x88002300, 2 ) => 0x2008C002

Of course one would use _rtol() or _lrotl().

But wait, they are non-ANSI 'functions' so you probably wont see them on the 
iSeries, shame about that eh ?

Here's the _lrotl() & _rotl() macro definitions;

#define _lrotr(x, c) ((((unsigned long)(x)) >> ((int) ((c) & 31))) | 
(((unsigned long)(x)) << ((int) ((32 - ((c) & 31))))))
#define _rotr(x, c) (unsigned int) _lrotr((unsigned long) x, c)

[ NOTE : _lrotr is all one long line ]

--phil

As an Amazon Associate we earn from qualifying purchases.

This thread ...
Follow On AppleNews
Return to Archive home page | Return to MIDRANGE.COM home page

This mailing list archive is Copyright 1997-2024 by midrange.com and David Gibbs as a compilation work. Use of the archive is restricted to research of a business or technical nature. Any other uses are prohibited. Full details are available on our policy page. If you have questions about this, please contact [javascript protected email address].

Operating expenses for this site are earned using the Amazon Associate program and Google Adsense.