U++ forum: Welcome to the forum

Search on this site

Search in forums

Home » Extra libraries, Code snippets, applications etc. » C++ language problems and code snippets » Time for little quiz!

Show: Today's Messages :: Show Polls :: Message Navigator
E-mail to friend

Re: Time for little quiz! [message #2253 is a reply to message #2219]

Wed, 05 April 2006 12:23

gprentice
Messages: 260
Registered: November 2005
Location: New Zealand

Experienced Member

ok, well sorry to be dumb but ... why do you want to avoid the conditional jump. Why do you think x.colorcount += (-q >> 31) & 1; is going to be more efficient than if(q) colorcount++; (or x.colorcount += bool(q); )

The compiler could be smart enough to generate a test and jump instead of shifting 31 times anyway or doing something else ??

BTW - I was thinking of 64 bit machines (regarding 32 bit ints) - but compilers for 64 bit seem to have standardized on 32 bits for int still?

Graeme

[Updated on: Wed, 05 April 2006 12:24]

Report message to a moderator

[Message index]

		Time for little quiz! By: mirek on Tue, 04 April 2006 14:02
		Re: Time for little quiz! By: unodgs on Tue, 04 April 2006 19:12
		Re: Time for little quiz! By: gprentice on Wed, 05 April 2006 12:31
		Re: Time for little quiz! By: fudadmin on Tue, 04 April 2006 20:04
		Re: Time for little quiz! By: mirek on Tue, 04 April 2006 20:36
		Re: Time for little quiz! By: victorb on Wed, 05 April 2006 10:21
		Re: Time for little quiz! By: mirek on Wed, 05 April 2006 10:53
		Re: Time for little quiz! By: mirek on Wed, 05 April 2006 10:54
		Re: Time for little quiz! By: gprentice on Wed, 05 April 2006 11:20
		Re: Time for little quiz! By: mirek on Wed, 05 April 2006 12:04
		Re: Time for little quiz! By: hojtsy on Wed, 05 April 2006 14:26
		Re: Time for little quiz! By: victorb on Wed, 05 April 2006 14:52
		Re: Time for little quiz! By: mirek on Wed, 05 April 2006 14:56
		Re: Time for little quiz! By: victorb on Wed, 05 April 2006 15:04
		Re: Time for little quiz! By: hojtsy on Wed, 05 April 2006 15:50
		Re: Time for little quiz! By: mirek on Wed, 05 April 2006 17:42
		Re: Time for little quiz! By: mirek on Wed, 05 April 2006 14:53
		Re: Time for little quiz! By: gprentice on Thu, 06 April 2006 14:29
		Re: Time for little quiz! By: mirek on Thu, 06 April 2006 15:56
		Re: Time for little quiz! By: victorb on Thu, 06 April 2006 16:17
		Re: Time for little quiz! By: mirek on Thu, 06 April 2006 16:25
		Re: Time for little quiz! By: nixnixnix on Tue, 02 September 2008 00:04
		Re: Time for little quiz! By: mirek on Tue, 02 September 2008 08:56
		Re: Time for little quiz! By: nixnixnix on Tue, 02 September 2008 21:54
		Re: Time for little quiz! By: mirek on Wed, 03 September 2008 14:18
		Re: Time for little quiz! By: nixnixnix on Wed, 03 September 2008 16:38
		Re: Time for little quiz! By: mrjt on Wed, 03 September 2008 16:51
		Re: Time for little quiz! By: mirek on Sun, 07 September 2008 10:12
		Re: Time for little quiz! By: gprentice on Wed, 05 April 2006 12:23
		Re: Time for little quiz! By: mirek on Wed, 05 April 2006 13:14

Previous Topic:	STL multimap
Next Topic:	explanation of c++ typedef line

Goto Forum:

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Wed Apr 30 07:50:54 CEST 2025

Total time taken to generate the page: 0.00839 seconds