Re: __builtin_expect in clang?
Re: __builtin_expect in clang?
- Subject: Re: __builtin_expect in clang?
- From: Jens Alfke <email@hidden>
- Date: Fri, 11 Nov 2011 13:24:58 -0800
On Nov 10, 2011, at 5:51 AM, Andreas Grosam wrote: I can't see any performance differences in a very hot code spot, when using it in branches, or omitting it, or even when giving the compiler *false* hints.
So, I'm wondering whether __builtin_expect is implemented in clang?
Disassemble the resulting code to see whether it makes a difference. It should affect the ordering of instructions and the sense of the conditional branches (usually the straight-line path is faster than the one that has to branch.)
—Jens |
Attachment:
smime.p7s
Description: S/MIME cryptographic signature
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Xcode-users mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden