bitwise & optimization

Fisnik Kastrati kastrati@informatik.uni-mannheim.de
Tue Jun 9 13:12:00 GMT 2015


To whom it may concern,

I'm turning to you with regards to an unwanted optimization that g++ (v. 
4.8.2) is generating, see the code in the following link:
http://goo.gl/3NVjyc

The assembly code generated for both methods "amp", "ampamp" is the 
practically the same, when using the optimization flag "-O3". However, 
I'm interested to have a single jump for the code in the method "amp", 
as branch misprediction penalty is very high otherwise. Is there any 
optmization flag that I should set, in order to avoid this feature when 
using "-O3"? I.e., I'd like a generated code similar to icc 13.


Thank you in advance



More information about the Gcc-help mailing list